Matter and radiation in the space between the star systems in a galaxy
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Is “now” just an illusion? Neil deGrasse Tyson and comic co-host Paul Mecurio answer questions on the Higgs Field, dark energy, and the feasibility of Dyson spheres with astrophysicist Hakeem Oluseyi.NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free here: https://startalkmedia.com/show/hubble-trouble-with-hakeem-oluseyi/Thanks to our Patrons Omar Video, Dan Carson, Joy Jack, Christine Bryant, Andrea Andrade, mahmoud hassan, Kyal Murray, Mercedes Dominguez, Christopher Rogalski, Eric De Bruin, Telmore, Gabe Ramshaw, James Edward Humphrey, Laurel Herbert, AJ Chambers, Bill WInn, Mayson Howell, Julianne Markow, Manthan Patel, Sonya Ponds, Depression Rawr, David Leys, Garon Devine, Vishal Ayeppun, BIIZZxGaming, Kurt Clark, Max Goldberg, Beth McDaniel, Shelby Staudenmaier, Kinnick Sutton, Jane von Schilling, Joanne karl, Walter Kinslow, and Eric Johnston for supporting us this week. Subscribe to SiriusXM Podcasts+ to listen to new episodes of StarTalk Radio ad-free and a whole week early.Start a free trial now on Apple Podcasts or by visiting siriusxm.com/podcastsplus.
What can gamma rays tell us about supernovae and galaxy formation? Neil deGrasse Tyson and co-host Chuck Nice sit down with astrophysicist Tim Paglione to explore high-energy cosmic phenomena, gamma rays, and the extreme events that create them.NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free here:https://startalkmedia.com/show/the-extreme-universe-with-tim-paglione/Thanks to our Patrons Alexander Storts, Chris Henderson, Micheal Mayo, Jose Lotzin, Rebecca Noland, Scientific Panda, Sander Bergheim, Aubrey Loftus, John Leon, Jaquelin Butkovic, Jesse McIntyre, Kelly Sheffield, Kaseim カセイム, Bradley Westbrook, Chris Rassette, Aquahood, BA_MPH_JD_PhD-aspirant, Ravenwingfeather, Kaity Sturgell, Norma Bazan, Mickey Brumfield, lamar Gibson, Bong Bong, Andrew Hayes, Billy Madison, Bruce Muller, parker martindale, James Pope, Carrie Williams, Robert Lester, Mike Bundy, and My Pug is a Bug for supporting us this week. Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.
Could slowing time increase mass? Do particles ever collide or do they just get really really close? Did anything go “bang” during the Big Bang? Neil deGrasse Tyson, co-host Paul Mecurio, and astrophysicist Charles Liu tackle these cosmic questions and more!NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free.Thanks to our Patrons Ty Jones, Mitchell Johnson, Bunny D, Julia Lord, Maurice, Garrett Wilson, TheRoyleKiwi, Velhaagrande, Sxyncerebral, Billy Caldwell, Debra Amandola, Dillon Fried, Urich, Mark Loucas, sparcis, James Hudson, Luc Miron, Debra, Richard Starr, Mark R, Mark Van Vrancken, Chirag Ahluwalia, Carole Fredrickson, Eddy, Chris Wells, Tomas E, Claire Richard, Andrew Atkins, Trevor steed, Srinivas N Ch, Pim Bliek, Joe Stradi, Austin Devillier, Johnny Le, Simao Voloch Neto, and Hardy Chen for supporting us this week. Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.
In this episode of the I Can't Sleep Podcast, drift off to sleep while learning about the interstellar medium. Discover the fascinating, yet complex, topic of space and satellites — though, truth be told, I didn't learn much myself! Maybe you'll absorb more than I did. Happy sleeping! Ad-Free Episodes Want an ad-free experience? Follow this link to support the podcast and get episodes with no ads: https://icantsleep.supportingcast.fm/ GhostBed Visit GhostBed.com/sleep and use promo code SLEEP for 50% off. ProLon Get 15% off Prolon's 5-day nutrition program at ProlonLife.com/ICANTSLEEP. Factor Head to FACTORMEALS.com/icantsleep50 and use code icantsleep50 to get 50% off. DoorDash Get 50% off up to $20 and zero delivery fees on your first order when you download the DoorDash app and enter code ICANTSLEEP. BetterHelp Visit BetterHelp.com/icantsleep today to get 10% off your first month HelloFresh Go to HelloFresh.com/50icantsleep and use code 50icantsleep for 50% off plus 15% off the next 2 months. Jupiter CBD Oil Save 20% off your first purchase by entering GETSLEEP upon checkout, or click here: https://www.getjupiter.com/share/icantsleep SleepPhones Follow this affiliate link to purchase headphones you can fall asleep with: https://www.sleepphones.com/?aff=793 then enter the code ICANTSLEEP10 at checkout to receive a discount. This content is derived from the Wikipedia article Interstellar Medium, available under the Creative Commons Attribution-ShareAlike (CC BY-SA) license. The article can be accessed at https://en.m.wikipedia.org/wiki/Interstellar_medium. Learn more about your ad choices. Visit megaphone.fm/adchoices
What happens to the stuff that falls into black holes? Do supergiants have sunspots? How can you do a gravitational slingshot from the Sun? Answering all these questions and more in this week's Overtime Q&A.
The science between the science! Kovi put on his special science goggles as he and Benjamin discussed the Interstellar Medium (ISM). The space between the stars is massive - but not empty! Going back to the 1860's we began to learn there's something out there, in 1904 we confirmed it, and since 1909 we learned that there's gas, dust, cosmic rays, shock-heating from supernovae, nebluae and more. Where does a nebula end and interstellar space begin? What IS a nebula? Join the nerd and the scientist is they wrap up their third season (their 30th episode!) with some learnin' and laughin'!
5/2/24: Congressman Jim McGovern on antisemitism, Speaker? Johnson, & Ukraine. Atty John Pucci on Trump's trial & contempt. Brian Adams w/ UMass Urban Agriculture expert, Ibrahim Ali: food for all. Ruth Griggs w/ Interstellar Medium's Jahian Cooper-Monize: rhythm and jazz.
5/2/24: Congressman Jim McGovern on antisemitism, Speaker? Johnson, & Ukraine. Atty John Pucci on Trump's trial & contempt. Brian Adams w/ UMass Urban Agriculture expert, Ibrahim Ali: food for all. Ruth Griggs w/ Interstellar Medium's Jahian Cooper-Monize: rhythm and jazz.
5/2/24: Congressman Jim McGovern on antisemitism, Speaker? Johnson, & Ukraine. Atty John Pucci on Trump's trial & contempt. Brian Adams w/ UMass Urban Agriculture expert, Ibrahim Ali: food for all. Ruth Griggs w/ Interstellar Medium's Jahian Cooper-Monize: rhythm and jazz.
5/2/24: Congressman Jim McGovern on antisemitism, Speaker? Johnson, & Ukraine. Atty John Pucci on Trump's trial & contempt. Brian Adams w/ UMass Urban Agriculture expert, Ibrahim Ali: food for all. Ruth Griggs w/ Interstellar Medium's Jahian Cooper-Monize: rhythm and jazz.
In this episode, Tejpreet will discuss the Interstellar medium also known as ISM in short. ISM is the celestial glue holding galaxies together. Discover its different types, the cosmic processes within, and its impact on space exploration. In dieser Folge spricht Tejpreet über das Interstellare Medium, auch kurz ISM genannt. Das ISM ist wie ein […] The post #16 The Interstellar Medium: Unravelling the Space Between Stars appeared first on Kanal K.
Most nebulae are of vast size; some are hundreds of light-years in diameter. A nebula that is visible to the human eye from Earth would appear larger, but no brighter, from close by
Dissecting the interstellar medium of a z=6 3 galaxy: X-shooter spectroscopy and HST imaging of the afterglow and environment of the Swift GRB 210905A by A. Saccardi et al. on Wednesday 30 November The study of the properties of galaxies in the first billion years after the Big Bang is one of the major topic of current astrophysics. Optical/near-infrared spectroscopy of the afterglows of long Gamma-ray bursts (GRBs) provide a powerful diagnostic tool to probe the interstellar medium (ISM) of their host galaxies and foreground absorbers, even up to the highest redshifts. We analyze the VLT/X-shooter afterglow spectrum of GRB 210905A, triggered by the Swift Neil Gehrels Observatory, and detect neutral-hydrogen, low-ionization, high-ionization, and fine-structure absorption lines from a complex system at z=6.3118, that we associate with the GRB host galaxy. We study the ISM properties of the host system, revealing the metallicity, kinematics and chemical abundance pattern. The total metallicity of the z~6.3 system is [M/H]=-1.75+/-0.13, after correcting for dust-depletion and taking into account alpha-element enhancement. In addition, we determine the overall amount of dust and dust-to-metal mass ratio (DTM) ([Zn/Fe]_fit=0.32+/-0.09, DTM=0.12+/-0.11). We find indications of nucleosynthesis due to massive stars and evidence of peculiar over-abundance of aluminium. From the analysis of fine-structure lines, we determine distances of several kpc for the low-ionization gas clouds closest to the GRB. Those farther distances are possibly due to the high number of ionizing photons. Using the HST/F140W image of the GRB field, we show the GRB host galaxy as well as multiple objects within 2" from the GRB. We discuss the galaxy structure and kinematics that could explain our observations, also taking into account a tentative detection of Lyman-alpha emission. Deep spectroscopic observations with VLT/MUSE and JWST will offer the unique possibility of combining our results with the ionized-gas properties, with the goal of better understanding how galaxies in the reionization era form and evolve. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.16524v1
Neural networks: solving the chemistry of the interstellar medium by Lorenzo Branca et al. on Wednesday 30 November Non-equilibrium chemistry is a key process in the study of the InterStellar Medium (ISM), in particular the formation of molecular clouds and thus stars. However, computationally it is among the most difficult tasks to include in astrophysical simulations, because of the typically high (>40) number of reactions, the short evolutionary timescales (about $10^4$ times less than the ISM dynamical time) and the characteristic non-linearity and stiffness of the associated Ordinary Differential Equations system (ODEs). In this proof of concept work, we show that Physics Informed Neural Networks (PINN) are a viable alternative to traditional ODE time integrators for stiff thermo-chemical systems, i.e. up to molecular hydrogen formation (9 species and 46 reactions). Testing different chemical networks in a wide range of densities ($-2< log n/{rm cm}^{-3}< 3$) and temperatures ($1 < log T/{rm K}< 5$), we find that a basic architecture can give a comfortable convergence only for simplified chemical systems: to properly capture the sudden chemical and thermal variations a Deep Galerkin Method is needed. Once trained ($sim 10^3$ GPUhr), the PINN well reproduces the strong non-linear nature of the solutions (errors $lesssim 10%$) and can give speed-ups up to a factor of $sim 200$ with respect to traditional ODE solvers. Further, the latter have completion times that vary by about $sim 30%$ for different initial $n$ and $T$, while the PINN method gives negligible variations. Both the speed-up and the potential improvement in load balancing imply that PINN-powered simulations are a very palatable way to solve complex chemical calculation in astrophysical and cosmological problems. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.15688v1
Dissecting the interstellar medium of a z=6 3 galaxy: X-shooter spectroscopy and HST imaging of the afterglow and environment of the Swift GRB 210905A by A. Saccardi et al. on Wednesday 30 November The study of the properties of galaxies in the first billion years after the Big Bang is one of the major topic of current astrophysics. Optical/near-infrared spectroscopy of the afterglows of long Gamma-ray bursts (GRBs) provide a powerful diagnostic tool to probe the interstellar medium (ISM) of their host galaxies and foreground absorbers, even up to the highest redshifts. We analyze the VLT/X-shooter afterglow spectrum of GRB 210905A, triggered by the Swift Neil Gehrels Observatory, and detect neutral-hydrogen, low-ionization, high-ionization, and fine-structure absorption lines from a complex system at z=6.3118, that we associate with the GRB host galaxy. We study the ISM properties of the host system, revealing the metallicity, kinematics and chemical abundance pattern. The total metallicity of the z~6.3 system is [M/H]=-1.75+/-0.13, after correcting for dust-depletion and taking into account alpha-element enhancement. In addition, we determine the overall amount of dust and dust-to-metal mass ratio (DTM) ([Zn/Fe]_fit=0.32+/-0.09, DTM=0.12+/-0.11). We find indications of nucleosynthesis due to massive stars and evidence of peculiar over-abundance of aluminium. From the analysis of fine-structure lines, we determine distances of several kpc for the low-ionization gas clouds closest to the GRB. Those farther distances are possibly due to the high number of ionizing photons. Using the HST/F140W image of the GRB field, we show the GRB host galaxy as well as multiple objects within 2" from the GRB. We discuss the galaxy structure and kinematics that could explain our observations, also taking into account a tentative detection of Lyman-alpha emission. Deep spectroscopic observations with VLT/MUSE and JWST will offer the unique possibility of combining our results with the ionized-gas properties, with the goal of better understanding how galaxies in the reionization era form and evolve. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.16524v1
The uncertain interstellar medium of high-redshift quiescent galaxies: Impact of methodology by Raphaël Gobat et al. on Tuesday 29 November How much gas and dust is contained in high-redshift quiescent galaxies (QGs) is currently an open question with relatively few and contradictory answers, as well as important implications for our understanding of the nature of star formation quenching processes at cosmic noon. Here we revisit far-infrared (FIR) observations of the REQUIEM-ALMA sample of six z = 1.6 - 3.2 QGs strongly lensed by intermediate-redshift galaxy clusters. We measured their continuum emission using priors obtained from high resolution near-infrared (NIR) imaging, as opposed to focusing on point-source extraction, converted it into dust masses using a FIR dust emission model derived from statistical samples of QGs, and compared the results to those of the reference work. We find that, while at least the most massive sample galaxy is indeed dust-poor, the picture is much more nuanced than previously reported. In particular, these more conservative constraints remain consistent with high dust fractions in early QGs. We find that these measurements are very sensitive to the adopted extraction method and conversion factors: the use of an extended light model to fit the FIR emission increases the flux of detections by up to 50% and the upper limit by up to a factor 6. Adding the FIR-to-dust conversion, this amounts to an order of magnitude difference in dust fraction, casting doubts on the power of these data to discriminate between star formation quenching scenarios. Unless these are identified by other means, mapping the dust and gas in high-redshift QGs will continue to require somewhat costly observations. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.14131v1
Neural networks: solving the chemistry of the interstellar medium by Lorenzo Branca et al. on Tuesday 29 November Non-equilibrium chemistry is a key process in the study of the InterStellar Medium (ISM), in particular the formation of molecular clouds and thus stars. However, computationally it is among the most difficult tasks to include in astrophysical simulations, because of the typically high (>40) number of reactions, the short evolutionary timescales (about $10^4$ times less than the ISM dynamical time) and the characteristic non-linearity and stiffness of the associated Ordinary Differential Equations system (ODEs). In this proof of concept work, we show that Physics Informed Neural Networks (PINN) are a viable alternative to traditional ODE time integrators for stiff thermo-chemical systems, i.e. up to molecular hydrogen formation (9 species and 46 reactions). Testing different chemical networks in a wide range of densities ($-2< log n/{rm cm}^{-3}< 3$) and temperatures ($1 < log T/{rm K}< 5$), we find that a basic architecture can give a comfortable convergence only for simplified chemical systems: to properly capture the sudden chemical and thermal variations a Deep Galerkin Method is needed. Once trained ($sim 10^3$ GPUhr), the PINN well reproduces the strong non-linear nature of the solutions (errors $lesssim 10%$) and can give speed-ups up to a factor of $sim 200$ with respect to traditional ODE solvers. Further, the latter have completion times that vary by about $sim 30%$ for different initial $n$ and $T$, while the PINN method gives negligible variations. Both the speed-up and the potential improvement in load balancing imply that PINN-powered simulations are a very palatable way to solve complex chemical calculation in astrophysical and cosmological problems. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.15688v1
The uncertain interstellar medium of high-redshift quiescent galaxies: Impact of methodology by Raphaël Gobat et al. on Monday 28 November How much gas and dust is contained in high-redshift quiescent galaxies (QGs) is currently an open question with relatively few and contradictory answers, as well as important implications for our understanding of the nature of star formation quenching processes at cosmic noon. Here we revisit far-infrared (FIR) observations of the REQUIEM-ALMA sample of six z = 1.6 - 3.2 QGs strongly lensed by intermediate-redshift galaxy clusters. We measured their continuum emission using priors obtained from high resolution near-infrared (NIR) imaging, as opposed to focusing on point-source extraction, converted it into dust masses using a FIR dust emission model derived from statistical samples of QGs, and compared the results to those of the reference work. We find that, while at least the most massive sample galaxy is indeed dust-poor, the picture is much more nuanced than previously reported. In particular, these more conservative constraints remain consistent with high dust fractions in early QGs. We find that these measurements are very sensitive to the adopted extraction method and conversion factors: the use of an extended light model to fit the FIR emission increases the flux of detections by up to 50% and the upper limit by up to a factor 6. Adding the FIR-to-dust conversion, this amounts to an order of magnitude difference in dust fraction, casting doubts on the power of these data to discriminate between star formation quenching scenarios. Unless these are identified by other means, mapping the dust and gas in high-redshift QGs will continue to require somewhat costly observations. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.14131v1
The uncertain interstellar medium of high-redshift quiescent galaxies: Impact of methodology by Raphaël Gobat et al. on Monday 28 November How much gas and dust is contained in high-redshift quiescent galaxies (QGs) is currently an open question with relatively few and contradictory answers, as well as important implications for our understanding of the nature of star formation quenching processes at cosmic noon. Here we revisit far-infrared (FIR) observations of the REQUIEM-ALMA sample of six z = 1.6 - 3.2 QGs strongly lensed by intermediate-redshift galaxy clusters. We measured their continuum emission using priors obtained from high resolution near-infrared (NIR) imaging, as opposed to focusing on point-source extraction, converted it into dust masses using a FIR dust emission model derived from statistical samples of QGs, and compared the results to those of the reference work. We find that, while at least the most massive sample galaxy is indeed dust-poor, the picture is much more nuanced than previously reported. In particular, these more conservative constraints remain consistent with high dust fractions in early QGs. We find that these measurements are very sensitive to the adopted extraction method and conversion factors: the use of an extended light model to fit the FIR emission increases the flux of detections by up to 50% and the upper limit by up to a factor 6. Adding the FIR-to-dust conversion, this amounts to an order of magnitude difference in dust fraction, casting doubts on the power of these data to discriminate between star formation quenching scenarios. Unless these are identified by other means, mapping the dust and gas in high-redshift QGs will continue to require somewhat costly observations. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.14131v1
Photochemistry and Heating Cooling of the Multiphase Interstellar Medium with UV Radiative Transfer for Magnetohydrodynamic Simulations by Jeong-Gyu Kim et al. on Monday 17 October We present an efficient heating/cooling method coupled with chemistry and ultraviolet (UV) radiative transfer, which can be applied to numerical simulations of the interstellar medium (ISM). We follow the time-dependent evolution of hydrogen species (H$_2$, H, H$^+$), assume carbon/oxygen species (C, C$^+$, CO, O, and O$^+$) are in formation-destruction balance given the non-steady hydrogen abundances, and include essential heating/cooling processes needed to capture thermodynamics of all ISM phases. UV radiation from discrete point sources and the diffuse background is followed through adaptive ray tracing and a six-ray approximation, respectively, allowing for H$_2$ self-shielding; cosmic ray (CR) heating and ionization are also included. To validate our methods and demonstrate their application for a range of density, metallicity, and radiation field, we conduct a series of tests, including the equilibrium curves of thermal pressure vs. density, the chemical and thermal structure in photo-dissociation regions, H I-to-H$_2$ transitions, and the expansion of H II regions and radiative supernova remnants. Careful treatment of photochemistry and CR ionization is essential for many aspects of ISM physics, including identifying the thermal pressure at which cold and warm neutral phases co-exist. We caution that many current heating and cooling treatments used in galaxy formation simulations do not reproduce the correct thermal pressure and ionization fraction in the neutral ISM. Our new model is implemented in the MHD code Athena and incorporated in the TIGRESS simulation framework, for use in studying the star-forming ISM in a wide range of environments. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.08024v1
Far-ultraviolet Dust Extinction and Molecular Hydrogen in the Diffuse Milky Way Interstellar Medium by Dries Van De Putte et al. on Thursday 13 October We aim to compare variations in the full-UV dust extinction curve (912-3000 Angstrom), with the HI/H$_2$/total H content along diffuse Milky Way sightlines, to investigate possible connections between ISM conditions and dust properties. We combine an existing sample of 75 UV extinction curves based on IUE and FUSE data, with atomic and molecular column densities measured through UV absorption. The H$_2$ column density data are based on existing Lyman-Werner absorption band models from earlier work on the extinction curves. Literature values for the HI column density were compiled, and improved for 23 stars by fitting a Ly$alpha$ profile to archived spectra. We discover a strong correlation between the H$_2$ column and the far-UV extinction, and the underlying cause is a linear relationship between H$_2$ and the strength of the far-UV rise feature. This extinction does not scale with HI, and the total H column scales best with $A(V)$ instead. The carrier of the far-UV rise therefore coincides with molecular gas, and further connections are shown by comparing the UV extinction features to the molecular fraction. Variations in the gas-to-extinction ratio $N(rm{H})/A(V)$ correlate with the UV-to-optical extinction ratio, and we speculate this could be due to coagulation or shattering effects. Based on the H$_2$ temperature, the strongest far-UV rise strengths are found to appear in colder and denser sightlines. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.04972v2
Far-ultraviolet Dust Extinction and Molecular Hydrogen in the Diffuse Milky Way Interstellar Medium by Dries Van De Putte et al. on Thursday 13 October We aim to compare variations in the full-UV dust extinction curve (912-3000 Angstrom), with the HI/H$_2$/total H content along diffuse Milky Way sightlines, to investigate possible connections between ISM conditions and dust properties. We combine an existing sample of 75 UV extinction curves based on IUE and FUSE data, with atomic and molecular column densities measured through UV absorption. The H$_2$ column density data are based on existing Lyman-Werner absorption band models from earlier work on the extinction curves. Literature values for the HI column density were compiled, and improved for 23 stars by fitting a Ly$alpha$ profile to archived spectra. We discover a strong correlation between the H$_2$ column and the far-UV extinction, and the underlying cause is a linear relationship between H$_2$ and the strength of the far-UV rise feature. This extinction does not scale with HI, and the total H column scales best with $A(V)$ instead. The carrier of the far-UV rise therefore coincides with molecular gas, and further connections are shown by comparing the UV extinction features to the molecular fraction. Variations in the gas-to-extinction ratio $N(rm{H})/A(V)$ correlate with the UV-to-optical extinction ratio, and we speculate this could be due to coagulation or shattering effects. Based on the H$_2$ temperature, the strongest far-UV rise strengths are found to appear in colder and denser sightlines. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.04972v2
Far-ultraviolet Dust Extinction and Molecular Hydrogen in the Diffuse Milky Way Interstellar Medium by Dries Van De Putte et al. on Tuesday 11 October We aim to compare variations in the full-UV dust extinction curve (912-3000 Angstrom), with the HI/H$_2$/total H content along diffuse Milky Way sightlines, to investigate possible connections between ISM conditions and dust properties. We combine an existing sample of 75 UV extinction curves based on IUE and FUSE data, with atomic and molecular column densities measured through UV absorption. The H$_2$ column density data are based on existing Lyman-Werner absorption band models from earlier work on the extinction curves. Literature values for the HI column density were compiled, and improved for 23 stars by fitting a Ly$alpha$ profile to archived spectra. We discover a strong correlation between the H$_2$ column and the far-UV extinction, and the underlying cause is a linear relationship between H$_2$ and the strength of the far-UV rise feature. This extinction does not scale with HI, and the total H column scales best with $A(V)$ instead. The carrier of the far-UV rise therefore coincides with molecular gas, and further connections are shown by comparing the UV extinction features to the molecular fraction. Variations in the gas-to-extinction ratio $N(rm{H})/A(V)$ correlate with the UV-to-optical extinction ratio, and we speculate this could be due to coagulation or shattering effects. Based on the H$_2$ temperature, the strongest far-UV rise strengths are found to appear in colder and denser sightlines. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.04972v1
Peptide Bonds in the Interstellar Medium: Facile Autocatalytic Formation from Nitriles on Water-Ice Grains by Boutheïna Kerkeni et al. on Thursday 22 September A recent suggestion that acetamide, ce{CH3C(O)NH2}, could be readily formed on water-ice grains by the acid induced addition of water across the ce{CN} bond is now shown to be valid. Computational modelling of the reaction between ce{R-CN} (R = H, ce{CH3}) and a cluster of 32 molecules of water and one ce{H3O+} proceeds auto-catalytically to form firstly a hydroxy imine ce{R-C(OH)=NH} and secondly an amide ce{R-C(O)NH2}. Quantum mechanical tunnelling, computed from small-curvature estimates, plays a key role in the rates of these reactions. This work represents the first credible effort to show how amides can be formed from abundant substrates, namely nitriles and water, reacting on a water-ice cluster containing catalytic amounts of hydrons in the interstellar medium with consequential implications towards the origins of life. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.10929v1
CLASSY IV: Exploring UV diagnostics of the interstellar medium in local high- z analogs at the dawn of the JWST era by Matilde Mingozzi et al. on Wednesday 21 September The COS Legacy Archive Spectroscopic SurveY (CLASSY) HST/COS treasury program provides the first high-resolution spectral catalogue of 45 local high-z analogues in the UV (1200-2000AA) to investigate their stellar and gas properties. We present a toolkit of UV interstellar medium (ISM) diagnostics, analyzing the main emission lines of CLASSY spectra (i.e., NIV]$lambdalambda$1483,87, CIV$lambdalambda$1548,51, HeII$lambda$1640, OIII]$lambdalambda$1661,6, SiIII]$lambdalambda$1883,92, CIII]$lambdalambda$1907,9). Specifically, we focus our investigation on providing accurate diagnostics for reddening, electron density and temperature, gas-phase metallicity and ionization parameter, taking into account the different ionization zones of the ISM. We calibrate our UV toolkit using well-known optical diagnostics, analyzing archival optical spectra for all the CLASSY targets. We find that UV density diagnostics estimate ne values that are ~1-2 dex higher (e.g., ne(CIII]$lambdalambda$}1907,9)~10$^4$cm$^{-3}$) than those inferred from their optical counterparts (e.g., ne([SII]$lambdalambda$6717,31)~10$^2$cm$^{-3}$). Te derived from the hybrid ratio OIII]$lambda$1666/[OIII]$lambda$}5007 proves to be a reliable Te diagnostic, with differences in 12+log(O/H) within ~$pm$0.3dex. We also investigate the relation between the stellar and gas E(B-V), finding consistent values at high specific star formation rates, while at low sSFR we confirm an excess of dust attenuation in the gas. Finally, we investigate UV line ratios and equivalent widths to provide correlations with 12+log(O/H) and log(U), but note there are degeneracies between the two. With this suite of UV-based diagnostics, we illustrate the pivotal role CLASSY plays in understanding the chemical and physical properties of high-z systems that JWST can observe in the rest-frame UV. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.09047v2
CLASSY IV: Exploring UV diagnostics of the interstellar medium in local high- z analogs at the dawn of the JWST era by Matilde Mingozzi et al. on Tuesday 20 September The COS Legacy Archive Spectroscopic SurveY (CLASSY) HST/COS treasury program provides the first high-resolution spectral catalogue of 45 local high-z analogues in the UV (1200-2000{AA}) to investigate their stellar and gas properties. We present a toolkit of UV interstellar medium (ISM) diagnostics, analyzing the main emission lines of CLASSY spectra (i.e., NIV]{lambda}{lambda}1483,87, CIV{lambda}{lambda}1548,51, HeII{lambda}1640, OIII]{lambda}{lambda}1661,6, SiIII]{lambda}{lambda}1883,92, CIII]{lambda}{lambda}1907,9). Specifically, we focus our investigation on providing accurate diagnostics for reddening, electron density and temperature, gas-phase metallicity and ionization parameter, taking into account the different ionization zones of the ISM. We calibrate our UV toolkit using well-known optical diagnostics, analyzing archival optical spectra for all the CLASSY targets. We find that UV density diagnostics estimate ne values that are ~1-2 dex higher (e.g., ne(CIII]{lambda}{lambda}1907,9)~10^4cm^{-3}) than those inferred from their optical counterparts (e.g., ne([SII]{lambda}{lambda}6717,31)~10^2cm^{-3}). Te derived from the hybrid ratio OIII]{lambda}1666/[OIII]{lambda}5007 proves to be a reliable Te diagnostic, with differences in 12+log(O/H) within ~+/-0.3dex. We also investigate the relation between the stellar and gas E(B-V), finding consistent values at high specific star formation rates, while at low sSFR we confirm an excess of dust attenuation in the gas. Finally, we investigate UV line ratios and equivalent widths to provide correlations with 12+log(O/H) and log(U), but note there are degeneracies between the two. With this suite of UV-based diagnostics, we illustrate the pivotal role CLASSY plays in understanding the chemical and physical properties of high-z systems that JWST can observe in the rest-frame UV. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.09047v1
Ammonia in the interstellar medium of a starbursting disc at z=2 6 by M. J. Doherty et al. on Tuesday 20 September We report the detection of the ground state rotational emission of ammonia, ortho-NH$_3$ $(J_K=1_0rightarrow0_0)$ in a gravitationally lensed, intrinsically hyperluminous, star-bursting galaxy at $z=2.6$. The integrated line profile is consistent with other molecular and atomic emission lines which have resolved kinematics well-modelled by a 5 kpc-diametre rotating disc. This implies that the gas responsible for NH$_3$ emission is broadly tracing the global molecular reservoir, but likely distributed in pockets of high density ($ngtrsim5times10^4$ cm$^{-3}$). With a luminosity of $2.8times10^{6}$ $L_odot$, the NH$_3$ emission represents $2.5times10^{-7}$ of the total infrared luminosity of the galaxy, comparable to the ratio observed in the Kleinmann-Low nebula in Orion and consistent with sites of massive star formation in the Milky Way. If $L_{rm NH_3}/L_{rm IR}$ serves as a proxy for the 'mode' of star formation, this hints that the nature of star formation in extreme starbursts in the early Universe is similar to that of Galactic star-forming regions, with a large fraction of the cold interstellar medium in this state, plausibly driven by a storm of violent disc instabilities in the gas-dominated disc. This supports the 'full of Orions' picture of star formation in the most extreme galaxies seen close to the peak epoch of stellar mass assembly. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.09268v1
CLASSY IV: Exploring UV diagnostics of the interstellar medium in local high- z analogs at the dawn of the JWST era by Matilde Mingozzi et al. on Tuesday 20 September The COS Legacy Archive Spectroscopic SurveY (CLASSY) HST/COS treasury program provides the first high-resolution spectral catalogue of 45 local high-z analogues in the UV (1200-2000{AA}) to investigate their stellar and gas properties. We present a toolkit of UV interstellar medium (ISM) diagnostics, analyzing the main emission lines of CLASSY spectra (i.e., NIV]{lambda}{lambda}1483,87, CIV{lambda}{lambda}1548,51, HeII{lambda}1640, OIII]{lambda}{lambda}1661,6, SiIII]{lambda}{lambda}1883,92, CIII]{lambda}{lambda}1907,9). Specifically, we focus our investigation on providing accurate diagnostics for reddening, electron density and temperature, gas-phase metallicity and ionization parameter, taking into account the different ionization zones of the ISM. We calibrate our UV toolkit using well-known optical diagnostics, analyzing archival optical spectra for all the CLASSY targets. We find that UV density diagnostics estimate ne values that are ~1-2 dex higher (e.g., ne(CIII]{lambda}{lambda}1907,9)~10^4cm^{-3}) than those inferred from their optical counterparts (e.g., ne([SII]{lambda}{lambda}6717,31)~10^2cm^{-3}). Te derived from the hybrid ratio OIII]{lambda}1666/[OIII]{lambda}5007 proves to be a reliable Te diagnostic, with differences in 12+log(O/H) within ~+/-0.3dex. We also investigate the relation between the stellar and gas E(B-V), finding consistent values at high specific star formation rates, while at low sSFR we confirm an excess of dust attenuation in the gas. Finally, we investigate UV line ratios and equivalent widths to provide correlations with 12+log(O/H) and log(U), but note there are degeneracies between the two. With this suite of UV-based diagnostics, we illustrate the pivotal role CLASSY plays in understanding the chemical and physical properties of high-z systems that JWST can observe in the rest-frame UV. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.09047v1
Using TeV Cosmic Rays to probe the Heliosphere's Boundary with the Local Interstellar Medium by Paolo Desiati et al. on Monday 19 September The heliosphere is the magnetic structure formed by the Sun's atmosphere extending into the local interstellar medium (ISM). The boundary separating the heliosphere from the ISM is a still largely unexplored region of space. Even though both Voyager spacecraft entered the local ISM and are delivering data, they are two points piercing a vast region of space at specific times. The heliospheric boundary regulates the penetration of MeV- GeV galactic cosmic rays (CR) in the inner heliosphere. Interstellar keV neutral atoms are crucial to the outer heliosphere since they can penetrate unperturbed and transfer energy to the solar wind. Missions such as NASA's IBEX and Cassini are designed to detect neutral atoms and monitor charge exchange processes at the heliospheric boundary. The heliosphere does not modulate the TeV CR intensity, but it does influence their arrival direction distribution. Ground-based CR observatories have provided accurate maps of CR anisotropy as a function of energy in the last couple of decades. Combining observations to produce all-sky coverage makes it possible to investigate the heliosphere's impact on TeV CR particles. We can numerically calculate the pristine TeV CR distribution in the local ISM with state-of-the-art heliosphere models. Only by subtracting the heliospheric influence is it possible to use TeV CR observations to infer propagation properties and the characteristics of magnetic turbulence in the ISM. Numerical calculations of CR particle trajectories through heliospheric models provide a complementary tool to probe the boundary region properties. A program boosting heliospheric modeling with emphasis on the boundary region and promoting combined CR experimental data analyses from multiple experiments benefits CR astrophysics and provides additional data and tools to explore the interaction between the heliosphere and the local ISM. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.08122v1
Directly tracing cool filamentary accretion over >100 kpc into the interstellar medium of a quasar host at z=1 by Sean D. Johnson et al. on Sunday 11 September We report the discovery of giant (50-100 kpc) [O II] emitting nebulae with the Multi-Unit Spectroscopic Explorer (MUSE) in the field of TXS 0206-048, a luminous quasar at z=1.13. An archival, down-the-barrel UV spectrum of the quasar shows absorption at velocities coincident with those of the extended nebulae, enabling new insights into inflows and outflows around the quasar host. One nebula exhibits a filamentary morphology extending over 120 kpc from the halo toward the quasar and intersecting with another nebula surrounding the quasar host with a radius of 50 kpc. The filamentary nebula has line-of-sight velocities >300 km/s from nearby galaxies but matches that of the nebula surrounding the quasar host where they intersect, consistent with filamentary accretion of cool inter- or circum-galactic medium or cooling hot halo gas. The kinematics of the nebulae surrounding the quasar host are unusual and complex, with one redshifted and one blue-shifted spiral-like structure. The nebular emission velocities at 5-10 kpc from the quasar match those of inflowing absorbing gas observed in a UV spectrum of the quasar. Together, the extended nebulae and associated redshifted absorption represent a compelling case of cool, filamentary gas accretion from halo scales into the extended interstellar medium and toward the nucleus of a massive quasar host galaxy at intermediate redshift. The inflow rate implied by the combination of emission and absorption constraints is orders-of-magnitude below levels required to sustain the quasar's radiative luminosity, indicating highly anisotropic or highly variable accretion. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.04245v1
In the mid-1980s, the discovery of complex carbon molecules drifting through the interstellar medium garnered significant attention, with possibly the most famous examples being Buckminsterfullerene, or “buckyballs” – spheres consisting of 60 or 70 carbon atoms. However, scientists have struggled to understand how these molecules can form in space. In a paper accepted for publication in the Journal of Physical Chemistry A, researchers from the University of Arizona suggest a surprisingly simple explanation. Do dying stars seed the interstellar medium? After exposing silicon carbide – a common ingredient of dust grains in planetary nebulae – to conditions similar to those found around dying stars, the researchers observed the spontaneous formation of carbon nanotubes, which are highly structured rod-like molecules consisting of multiple layers of carbon sheets. The findings were presented on June 16 at the 240th Meeting of the American Astronomical Society in Pasadena, California. Led by UArizona researcher Jacob Bernal, the work builds on research published in 2019, when the group showed that they could create buckyballs using the same experimental setup. The work suggests that buckyballs and carbon nanotubes could form when the silicon carbide dust made by dying stars is hit by high temperatures, shock waves and high-energy particles, leaching silicon from the surface and leaving carbon behind. The findings support the idea that dying stars may seed the interstellar medium with nanotubes and possibly other complex carbon molecules. The results have implications for astrobiology, as they provide a mechanism for concentrating carbon that could then be transported to planetary systems. “We know from infrared observations that buckyballs populate the interstellar medium,” said Bernal, a postdoctoral research associate in the UArizona Lunar and Planetary Laboratory. “The big problem has been explaining how these massive, complex carbon molecules could possibly form in an environment saturated with hydrogen, which is what you typically have around a dying star.” The formation of carbon-rich molecules, let alone species containing pure carbon, in the presence of hydrogen is virtually impossible due to thermodynamic laws. The new study findings offer an alternative scenario: Instead of assembling individual carbon atoms, buckyballs and nanotubes could result by simply rearranging the structure of graphene – single-layered carbon sheets that are known to form on the surface of heated silicon carbide grains. This is exactly what Bernal and his co-authors observed when they heated commercially available silicon carbide samples to temperatures occurring in dying or dead stars and imaged them. As the temperature approached 1,050 degrees Celsius, small hemispherical structures with the approximate size of about 1 nanometer were observed at the grain surface. Within minutes of continued heating, the spherical buds began to grow into rod-like structures, containing several graphene layers with curvature and dimensions indicating a tubular form. The resulting nanotubules ranged from about 3 to 4 nanometers in length and width, larger than buckyballs. The largest imaged specimens were comprised of more than four layers of graphitic carbon. During the heating experiment, the tubes were observed to wiggle before budding off the surface and getting sucked into the vacuum surrounding the sample. “We were surprised we could make these extraordinary structures,” Bernal said. “Chemically, our nanotubes are very simple, but they are extremely beautiful.” Named after their resemblance to architectural works by Richard Buckminster Fuller, fullerenes are the largest molecules currently known to occur in interstellar space, which for decades was believed to be devoid of any molecules containing more than a few atoms, 10 at most. It is now well established that the fullerenes C60 and C70, which contain 60 or 70 carbon atoms, respectively, are common ing...
In this episode of Stardust MQ, Cameron speaks to post-graduate researcher Anita Petzler about her study of tracers on expanding H II regions in the Interstellar Medium
This week on Episode 498 of Priority One: We Trek Out what Spiner has to say about a TNG reboot? A new book featuring Cristóbal Rios is on the horizon. And we’ve learned what the next event in Star Trek Online is slated to be. Of course, as always, before we wrap up the show, we’ll open hailing frequencies for your incoming messages This Week’s Community Questions are: CQ: If there was a feature film reboot of the Next Generation, who would you cast as Data? AND CQ: What bridge officer traits do you rely on for your builds in Star Trek Online? Let us know on social media like Facebook, Twitter, or by visiting our website! TREK IT OUT Brent Spiner - Next Gen Reboot Brent Spiner recently sat down with SYFY Wire to discuss a plethora of things from his upcoming book, “Fan Fiction: A Mem-noir: Inspired by True Events,” to what tips he would give to Patrick Stewart on portraying an android Jean-Luc for Picard season 2. Spoiler alert by the way. Amongst the many topics touched upon was one in particular which will undoubtedly provide some Trek trivia fodder. It turns out that before Spiner suggested that he play Dr. Noonian Soong, Data’s creator, a different actor had already been cast in the role. Keye Luke was set to play the part originally. Having a role in the TOS episode, Whom Gods Destroy, Luke is most well known as Master Po from the Kung Fu TV series in the 70’s and as the shop owner who cares for Gizmo in the Gremlins movies. Spiner was unaware that an actor had already been cast and tried to rescind his suggestion afterwards. But the creative team decided to have Spiner play the part and begin building the impressive list of characters and personalities that Spiner would ultimately play. And which of those characters is his favorite to play? ”I always liked playing Lore, because Lore is really more like me than any of the other characters I’ve ever played because I am evil.” Spiner also credits Michael Westmore with helping him create the character of Noonian Soong. Talking about the Soong makeup, Spiner said, “When he put it on me and I looked in the mirror, I knew exactly how to play the part. I owe him a lot, because I think we collaborated on that.” Later on in the interview Spiner was asked about the future of Star Trek. In addition to enjoying the recent Star Trek movies, Spiner said, “I think that sooner or later, they’re going to do a reboot, a motion picture version of Next Generation, and cast some young guys in our parts.” Star Trek: Picard: Rogue Elements If you were a fan of Spanish Han Solo… I mean, Cristóbal Rios -- Captain of La Sirena… then you might want to mark your calendars for August 17th! New York Times Bestseller, John Jackson Miller is taking you on a spicy adventure featuring your favorite tall, dark, spanish drink of water. Based on events occurring PRIOR to meeting Picard and taking on the Synth Plot to rid the galaxy of all organic life, Miller’s book, “Rogue Elements” takes on adventures with ”exotic lovers and locales... as well as dangers galore -- and Rios learns the hard way that good crew members are hard to find”. ASTROMETRICS REPORT By Dr. Robert Hurt Image: NASA/JPL For this week's Astrometrics Report, what else could I talk about other than the incredible feat of interplanetary gymnastics, with NASA's Jet Propulsion Laboratory once again sticking the landing by delivering the Perseverance rover to the surface of Mars? There were a lot of happy faces in Mission Control on February 18th, when the "all's well" signals came back from the Red Planet. You may have a sense of déjà vu looking at this new rover since it bears a strong resemblance to its younger sibling, the highly-successful Curiosity rover. This is no accident: Perseverance is essentially built on the same chassis. When you have a flexible design that's been proven to work, it makes sense to leverage that technology moving forward. Of course, Perseverance brings a lot of new technologies to bear. NASA's website explains that the mission addresses high-priority science goals for Mars exploration, including key questions about the potential for life on Mars. The mission takes the next step by not only seeking signs of habitable conditions on Mars in the ancient past, but also searching for signs of past microbial life itself. Image: NASA/JPL It also provides opportunities to gather knowledge and demonstrate technologies to address the challenges of future human expeditions to Mars. These include testing a method for producing oxygen from the Martian atmosphere, identifying other resources like subsurface water, improving landing techniques, and characterizing weather, dust, and other environmental conditions that could affect future astronauts living and working on Mars. Personally I'm most excited over the Ingenuity Mars Helicopter, a technology testbed to pave the way for more flexible aerial explorations of our neighboring planet. Building a drone for Mars is not trivial: when the surface pressure is only 1% that of Earth at sea level, you have to crank out a lot more lift than your typical off-the-shelf drone. Everything we learn from Ingenuity's performance will help us design a new generation of flying laboratories that can be sent to Mars and other places in the Solar System. But if you just want to watch something cool, another mission first includes actual video document of the descent and landing. This is the first time we can see the mind-numbing complexity of the landing sequence directly, instead of relying on visual effects simulations. Adding the diagnostic cameras did cut into the tightly-controlled weight budget for the mission, but it will give engineers lots of insight to how well the technologies are performing...in addition to giving us a great show. Perseverance has already sent back an incredible panorama of its landing site within the Jezero Crater, and even recording what the surface of Mars sounds like. Scientists think that about 3.5 billion years ago, Jezero Crater was actually a lake before Mars lost most of its atmosphere and surface water. This was identified as an ideal place to look for any hints that Mars could have harbored life early in its history. There won't be any quick answers here, but the instruments on Perseverance are well-suited to study the geological clues in this exciting new locale. Make sure to keep an eye on NASA's website in the coming months to see what Perseverance learns. Star Trek Gaming News by Thomas Reynolds, Shane Hoover & Anthony Cox Extinction Events and Campaign Trails By Thomas Reynolds The 11th Anniversary celebrations are over, captains. So now it’s obviously time for another grind. As first seen in an unintended Ten Forward stream leak, the next STO event is a 3-week Voth Advance reprise, from February 25th-March 18th, probably following the daily-TFO-for-14-days format. Players can earn Molor’s Flaming Sword by completing either “The Breach” or “Storming the Spire” daily during the event. This round of the Voth Advance also starts off the third of STO’s popular Event Campaigns. But will it be worth the fatigue this time around? The grand prize for 2021 is either 1500 Lobi, a T6 Zen Store ship, or a Premium T6 Starship Choice. So I’d say yes, yes it is. Read more about the event in our shownotes. Fair Trait Associations By Thomas Reynolds Bridge crew: even if they aren’t doing kick flips all the time, they’re an essential part of any Star Trek story. They tap consoles, tap each other, and help the audience tap into each show’s heart and history. And sometimes, we even learn their names! Although maybe it takes until Season 2 to get there. In Star Trek Online, your bridge crew serves another purpose beyond away parties and eye candy. As your species, career, and lockbox luck give you stat-improving traits, boff traits improve your captainly effectiveness too. Some are useful in very, very specific situations. Nelen Exil --- HE gets knocked down, then he gets up again, so they’ll never keep him down. Might not sound useful to your phaser-basted corpse, but a team medic who isn’t one-and-done isn’t a bad idea. However, the most highly-prized boffs offer traits for space combat and ground. Everyone–not just DPS chasers and PvPers–should look around their bridge and ask if they’re truly getting peak performance. Space traits won’t make-or-break builds, but don’t leave weapon crit bonuses and hull regen buffs on the ready room table. We asked...well, solicited…alright, pestered the P1 production crew to share space boff traits they prefer on their builds. We’ll discuss a few here for your listening pleasure, with the full list in the shownotes. Star Trek Timelines Adds New “Crew Retrieval” System By Anthony Cox Over in the mobile world of Star Trek gaming, Star Trek Timelines has added a new feature to help players retrieve specific crew members for their collections. Timelines is a game where you collect crew members from all the various timelines and time periods of Star Trek, assemble them on a team, and battle against mission requirements. It’s pretty much Star Trek: Pokemon. There are several rarities of crew members and it can sometimes be frustrating trying to collect that one specific character you need to complete your collections. Well, Tilting Point, the relatively new owners of Star Trek Timelines, has released a helpful, yet somewhat complicated new system. The Crew Retrieval system. The scan feature, which is not new, is used to gain random items throughout the day. Scans were free every 3 hours. Now, scans cost a new currency called ISM or Interstellar Medium. And each scan result not only grants you a random item, but also gives you a chance to gain a constellation. Every time you scan without gaining a constellation the chance you’ll get one on the next scan increases. So, what do you do with constellations. Well, using more ISM you can open constellations which will grant you Polestars. What’s a Polestar you ask? A Polestar gives you the ability to narrow down a single variable to reduce the pool of crew members from which you’re trying to retrieve. These variables can be a skill, a trait, or a rarity. Once you’ve set up to 4 polestars you then spend credits and, you guessed it, a NEW type of currency called Quantum, to retrieve your crew member. If you’ve narrowed it down enough it might not be a random pull. For example, let’s say you’re looking for Grand Nagus Rom, he’s a 5 star rarity, has the traits Ferengi, Diplomat, Politician, and has the skills Command, Diplomacy, and Engineer. So you could use a Polestar for rarity 5-star, a Polestar for the Ferengi trait, one for the Politician trait, and one for the Engineer skill. That will hopefully narrow down the pool to just Grand Nagus Rom. Then spend your credits and quantums and see what you get. When a Polestar is pulled from a constellation it already has a specific attribute. Either a specific rarity, trait, or skill. So you’ll need to find the right ones if you’re looking to zone in on that specific crew member. Star Trek Timelines is available in the Google Play Store, Apple App Store, Steam, Facebook, and Windows App Store.
This week on Episode 498 of Priority One: We Trek Out what Spiner has to say about a TNG reboot? A new book featuring Cristóbal Rios is on the horizon. And we've learned what the next event in Star Trek Online is slated to be. Of course, as always, before we wrap up the show, we'll open hailing frequencies for your incoming messages This Week's Community Questions are: CQ: If there was a feature film reboot of the Next Generation, who would you cast as Data? AND CQ: What bridge officer traits do you rely on for your builds in Star Trek Online? Let us know on social media like Facebook, Twitter, or by visiting our website! TREK IT OUT Brent Spiner - Next Gen Reboot Brent Spiner recently sat down with SYFY Wire to discuss a plethora of things from his upcoming book, “Fan Fiction: A Mem-noir: Inspired by True Events,” to what tips he would give to Patrick Stewart on portraying an android Jean-Luc for Picard season 2. Spoiler alert by the way. Amongst the many topics touched upon was one in particular which will undoubtedly provide some Trek trivia fodder. It turns out that before Spiner suggested that he play Dr. Noonian Soong, Data's creator, a different actor had already been cast in the role. Keye Luke was set to play the part originally. Having a role in the TOS episode, Whom Gods Destroy, Luke is most well known as Master Po from the Kung Fu TV series in the 70's and as the shop owner who cares for Gizmo in the Gremlins movies. Spiner was unaware that an actor had already been cast and tried to rescind his suggestion afterwards. But the creative team decided to have Spiner play the part and begin building the impressive list of characters and personalities that Spiner would ultimately play. And which of those characters is his favorite to play? ”I always liked playing Lore, because Lore is really more like me than any of the other characters I've ever played because I am evil.” Spiner also credits Michael Westmore with helping him create the character of Noonian Soong. Talking about the Soong makeup, Spiner said, “When he put it on me and I looked in the mirror, I knew exactly how to play the part. I owe him a lot, because I think we collaborated on that.” Later on in the interview Spiner was asked about the future of Star Trek. In addition to enjoying the recent Star Trek movies, Spiner said, “I think that sooner or later, they're going to do a reboot, a motion picture version of Next Generation, and cast some young guys in our parts.” Star Trek: Picard: Rogue Elements If you were a fan of Spanish Han Solo… I mean, Cristóbal Rios -- Captain of La Sirena… then you might want to mark your calendars for August 17th! New York Times Bestseller, John Jackson Miller is taking you on a spicy adventure featuring your favorite tall, dark, spanish drink of water. Based on events occurring PRIOR to meeting Picard and taking on the Synth Plot to rid the galaxy of all organic life, Miller's book, “Rogue Elements” takes on adventures with ”exotic lovers and locales... as well as dangers galore -- and Rios learns the hard way that good crew members are hard to find”. ASTROMETRICS REPORT By Dr. Robert Hurt Image: NASA/JPL For this week's Astrometrics Report, what else could I talk about other than the incredible feat of interplanetary gymnastics, with NASA's Jet Propulsion Laboratory once again sticking the landing by delivering the Perseverance rover to the surface of Mars? There were a lot of happy faces in Mission Control on February 18th, when the "all's well" signals came back from the Red Planet. You may have a sense of déjà vu looking at this new rover since it bears a strong resemblance to its younger sibling, the highly-successful Curiosity rover. This is no accident: Perseverance is essentially built on the same chassis. When you have a flexible design that's been proven to work, it makes sense to leverage that technology moving forward. Of course, Perseverance brings a lot of new technologies to bear. NASA's website explains that the mission addresses high-priority science goals for Mars exploration, including key questions about the potential for life on Mars. The mission takes the next step by not only seeking signs of habitable conditions on Mars in the ancient past, but also searching for signs of past microbial life itself. Image: NASA/JPL It also provides opportunities to gather knowledge and demonstrate technologies to address the challenges of future human expeditions to Mars. These include testing a method for producing oxygen from the Martian atmosphere, identifying other resources like subsurface water, improving landing techniques, and characterizing weather, dust, and other environmental conditions that could affect future astronauts living and working on Mars. Personally I'm most excited over the Ingenuity Mars Helicopter, a technology testbed to pave the way for more flexible aerial explorations of our neighboring planet. Building a drone for Mars is not trivial: when the surface pressure is only 1% that of Earth at sea level, you have to crank out a lot more lift than your typical off-the-shelf drone. Everything we learn from Ingenuity's performance will help us design a new generation of flying laboratories that can be sent to Mars and other places in the Solar System. But if you just want to watch something cool, another mission first includes actual video document of the descent and landing. This is the first time we can see the mind-numbing complexity of the landing sequence directly, instead of relying on visual effects simulations. Adding the diagnostic cameras did cut into the tightly-controlled weight budget for the mission, but it will give engineers lots of insight to how well the technologies are performing...in addition to giving us a great show. Perseverance has already sent back an incredible panorama of its landing site within the Jezero Crater, and even recording what the surface of Mars sounds like. Scientists think that about 3.5 billion years ago, Jezero Crater was actually a lake before Mars lost most of its atmosphere and surface water. This was identified as an ideal place to look for any hints that Mars could have harbored life early in its history. There won't be any quick answers here, but the instruments on Perseverance are well-suited to study the geological clues in this exciting new locale. Make sure to keep an eye on NASA's website in the coming months to see what Perseverance learns. Star Trek Gaming News by Thomas Reynolds, Shane Hoover & Anthony Cox Extinction Events and Campaign Trails By Thomas Reynolds The 11th Anniversary celebrations are over, captains. So now it's obviously time for another grind. As first seen in an unintended Ten Forward stream leak, the next STO event is a 3-week Voth Advance reprise, from February 25th-March 18th, probably following the daily-TFO-for-14-days format. Players can earn Molor's Flaming Sword by completing either “The Breach” or “Storming the Spire” daily during the event. This round of the Voth Advance also starts off the third of STO's popular Event Campaigns. But will it be worth the fatigue this time around? The grand prize for 2021 is either 1500 Lobi, a T6 Zen Store ship, or a Premium T6 Starship Choice. So I'd say yes, yes it is. Read more about the event in our shownotes. Fair Trait Associations By Thomas Reynolds Bridge crew: even if they aren't doing kick flips all the time, they're an essential part of any Star Trek story. They tap consoles, tap each other, and help the audience tap into each show's heart and history. And sometimes, we even learn their names! Although maybe it takes until Season 2 to get there. In Star Trek Online, your bridge crew serves another purpose beyond away parties and eye candy. As your species, career, and lockbox luck give you stat-improving traits, boff traits improve your captainly effectiveness too. Some are useful in very, very specific situations. Nelen Exil --- HE gets knocked down, then he gets up again, so they'll never keep him down. Might not sound useful to your phaser-basted corpse, but a team medic who isn't one-and-done isn't a bad idea. However, the most highly-prized boffs offer traits for space combat and ground. Everyone–not just DPS chasers and PvPers–should look around their bridge and ask if they're truly getting peak performance. Space traits won't make-or-break builds, but don't leave weapon crit bonuses and hull regen buffs on the ready room table. We asked...well, solicited…alright, pestered the P1 production crew to share space boff traits they prefer on their builds. We'll discuss a few here for your listening pleasure, with the full list in the shownotes. Star Trek Timelines Adds New “Crew Retrieval” System By Anthony Cox Over in the mobile world of Star Trek gaming, Star Trek Timelines has added a new feature to help players retrieve specific crew members for their collections. Timelines is a game where you collect crew members from all the various timelines and time periods of Star Trek, assemble them on a team, and battle against mission requirements. It's pretty much Star Trek: Pokemon. There are several rarities of crew members and it can sometimes be frustrating trying to collect that one specific character you need to complete your collections. Well, Tilting Point, the relatively new owners of Star Trek Timelines, has released a helpful, yet somewhat complicated new system. The Crew Retrieval system. The scan feature, which is not new, is used to gain random items throughout the day. Scans were free every 3 hours. Now, scans cost a new currency called ISM or Interstellar Medium. And each scan result not only grants you a random item, but also gives you a chance to gain a constellation. Every time you scan without gaining a constellation the chance you'll get one on the next scan increases. So, what do you do with constellations. Well, using more ISM you can open constellations which will grant you Polestars. What's a Polestar you ask? A Polestar gives you the ability to narrow down a single variable to reduce the pool of crew members from which you're trying to retrieve. These variables can be a skill, a trait, or a rarity. Once you've set up to 4 polestars you then spend credits and, you guessed it, a NEW type of currency called Quantum, to retrieve your crew member. If you've narrowed it down enough it might not be a random pull. For example, let's say you're looking for Grand Nagus Rom, he's a 5 star rarity, has the traits Ferengi, Diplomat, Politician, and has the skills Command, Diplomacy, and Engineer. So you could use a Polestar for rarity 5-star, a Polestar for the Ferengi trait, one for the Politician trait, and one for the Engineer skill. That will hopefully narrow down the pool to just Grand Nagus Rom. Then spend your credits and quantums and see what you get. When a Polestar is pulled from a constellation it already has a specific attribute. Either a specific rarity, trait, or skill. So you'll need to find the right ones if you're looking to zone in on that specific crew member. Star Trek Timelines is available in the Google Play Store, Apple App Store, Steam, Facebook, and Windows App Store.
A brief description of the main components of the interstellar medium, which is the stuff in space between the stars.
NASA has selected the next landing site for its future Mars rover, Mars 2020. Jezero Crater is an incredible ancient river delta spilling in to the side of a crater. But what really makes it special, plus how and why did NASA pick it? Jake is joined by planetary scientist Tim Goudge, who led the advocacy of Jezero through the process, to explain its charm. We talk NASA's Mars 2020 rover and Jezero Crater NASA Announces Jezero Crater as Landing Site Mars 2020 Rover Previous Coverage of the Mars 2020 Rover Episode 10 - Science meets Engineering on the 2020 Rover (feat. Sarah Milkovich) Episode 20 - Mars 2020 Landing Site Candidates Episode 48 - Zooming in on Mars (feat. Melissa Rice and Elsa Jensen) Follow Tim Goudge Tim's Website Tim's Twitter (@timgoudge) Follow Jake & WeMartians Website (www.wemartians.com) Patreon (www.patreon.com/wemartians) The WeMartians Travel Grant WeMartians Shop (shop.wemartians.com) Check out all the new merchandise out in time for the holidays! Twitter (@we_martians) Jake’s Twitter (@JakeOnOrbit) Listener Survey 2018 New Merchandise! We've got a whole bunch of new merchandise in our shop! Check out the new designs, including Off-Nominal gear! Our Sponsor WeMartians is sponsored by MOVA Globes. Visit the site and use the code WEMARTIANS for 10% off your order of one of these really great looking pieces shipping to the Americas. They rotate without cords or batteries! Patrons, check your Patreon account for a special Patron-only discount code. Thanks to MOVA Globes for helping us explore Mars together. We wanted to feature a cool globe this episode. Given that Voyager 2 made the news this week when it entered the Interstellar Medium, we thought it appropriate to feature the Neptune design. Neptune has only ever been visited by Voyager 2! Check out that Small Dark Spot! WeMartians music is “RetroFuture”, “Electrodoodle”, and “On My Way” by Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0 License http://creativecommons.org/licenses/by/3.0/
In this class we discuss binary stars and how they are used to determine stellar mass. We then begin to discuss the Interstellar Medium.
Karin Sandstrom studies the interstellar medium - the dust and gas in galaxies and between stars, and especially how ultraviolet light interacts with soot-like polycyclic aromatic hydrocarbons. That, she says, is key to everything - how stars (and planets) form, how galaxies evolve, and perhaps how life emerged. Series: "Women in Science" [Science] [Show ID: 30014]
Karin Sandstrom studies the interstellar medium - the dust and gas in galaxies and between stars, and especially how ultraviolet light interacts with soot-like polycyclic aromatic hydrocarbons. That, she says, is key to everything - how stars (and planets) form, how galaxies evolve, and perhaps how life emerged. Series: "Women in Science" [Science] [Show ID: 30014]
Karin Sandstrom studies the interstellar medium - the dust and gas in galaxies and between stars, and especially how ultraviolet light interacts with soot-like polycyclic aromatic hydrocarbons. That, she says, is key to everything - how stars (and planets) form, how galaxies evolve, and perhaps how life emerged. Series: "Women in Science" [Science] [Show ID: 30014]
Karin Sandstrom studies the interstellar medium - the dust and gas in galaxies and between stars, and especially how ultraviolet light interacts with soot-like polycyclic aromatic hydrocarbons. That, she says, is key to everything - how stars (and planets) form, how galaxies evolve, and perhaps how life emerged. Series: "Women in Science" [Science] [Show ID: 30014]
Dr. Slava Turyshev from JPL/Caltech talks about Exploring in the Interstellar Medium during the short course at the Keck Institute for Space Studies on September 8, 2014. In conjunction with the KISS program Science and Enabling Technologies to Explore the Interstellar Medium
Professor Ed Stone from Caltech talks about Exploring in the Interstellar Medium during the short course at the Keck Institute for Space Studies on September 8, 2014. In conjunction with the KISS program Science and Enabling Technologies to Explore the Interstellar Medium
Professor Mike Brown from Caltech talks about Exploring in the Interstellar Medium during the short course at the Keck Institute for Space Studies on September 8, 2014. In conjunction with the KISS program Science and Enabling Technologies to Explore the Interstellar Medium
Dr. Ralph McNutt from APL/Johns Hopkins University presents Exploring in the Interstellar Medium during the short course at the Keck Institute for Space Studies on September 8, 2014. In conjunction with the KISS program Science and Enabling Technologies to Explore the Interstellar Medium
Professor Freeman Dyson from IAS, Princeton presents Exploring in the Interstellar Medium during the short course at the Keck Institute for Space Studies on September 8, 2014. In conjunction with the KISS program Science and Enabling Technologies to Explore the Interstellar Medium
Stardust returns Like this podcast? Please help us by supporting the Naked Scientists
Stardust returns Like this podcast? Please help us by supporting the Naked Scientists
Voyager 1's own record of the plasma vibrations in its vicinity conclusively show that it has reached the space between the stars. John Matson reports
Dr. Jokipii’s research concerns many areas primarily related to plasmas and the transport and acceleration of cosmic rays and energetic particles in the solar wind and in the galaxy. Major current thrusts revolve around work on the Voyager and ACE space missions, for which he and his group are guest investigators, specializing in theoretical interpretaion and modeling of the observations. Specifically, Dr. Jokipii’s group is currently in the midst of an extensive program of theoretical research into shock waves in turbulent astrophysical plasmas. This involves extensive theoretical work and three-dimensional simulations, which are exceedingly demanding of computer resources. His lecture was given on October 29, 2010.
Preface What is the interstellar medium? The term "interstellar medium" (ISM) refers
What is the ISM What is the ISM made of: a
A census of systems in the ISM We continue our survey
Abstract: The Sun and its radially flowing solar wind blow a huge bubble, a few hundred AU in scale, in the interstellar medium. This results in a very complicated interaction between the resulting heliosphere and the local interstellar medium. The solar wind is a very nearly completely ionized plasma, whereas the local interstellar medium is only partly ionized, and therefore consists of both charged and neutral particles. The collision mean free paths of all species are much larger than the scale of the heliosphere, so the interactions do not involve particle-particle scattering. The ions interact via collective electromagnetic interactions and the neutrals can be ionized by solar radiation and through charge exchange with ions. his region was predicted decades ago and, recently, the two Voyager spacecraft are traversing in this region, sending back data. The IBEX (Interstellar Boundary EXplorer) mission, launched on October 19, 2008, was developed to observe this region remotely, from Earth orbit, by measuring energetic neutral atoms (ENA) resulting from the interaction with the neutral part of the Interstellar Medium. Because of the lack of collisions and the relatively high energy of the ENA, they travel on nearly straight lines, and can be used much like photons to map the sky. IBEX began sending data to ground six months after launch, and is still doing so. In spite of intensivetheoretical an modeling efforts over the past decades, much of what is observed was totally unexpected and not even hinted at in the models. The observed ENA maps, at the higher energies observed, revealed an intense "ribbon" of significantly enhanced intensity, some 15 degrees wide, encircling the solar system. This unexpected feature and other aspects of the observations have required new models and interpretations. Dr. J. Randy Jokipii is Regents' Professor, Theoretical astrophysics, space physics at the University of Arizona. Presented Oct. 29, 2010.
What would an extrasolar observer see of our solar system? We find out in this month's Naked Astronomy as well as explore the events that led to climate change on a cosmic scale. Plus, news of an asteroid flyby, surfing Venus' atmosphere and the end of the WMAP. We take on your space science questions, including the best place to site a space elevator! Like this podcast? Please help us by supporting the Naked Scientists
What would an extrasolar observer see of our solar system? We find out in this month's Naked Astronomy as well as explore the events that led to climate change on a cosmic scale. Plus, news of an asteroid flyby, surfing Venus' atmosphere and the end of the WMAP. We take on your space science questions, including the best place to site a space elevator! Like this podcast? Please help us by supporting the Naked Scientists