Podcasts about vlbi

What's it like to stand at the edge of human knowledge, where we don't know what leap forward in understanding the next technological innovation will herald? To find out, Dr. Charles Liu and co-host Allen Liu welcome Dr. Melodie Kao, resident radio astronomer at the Lowell Observatory in Flagstaff, AZ, where Clyde Tombaugh discovered Pluto back in 1930. (And if you're scratching your heads saying, “What's a radio astronomer doing at an optical observatory?” you're not alone. Short answer: Melodie convinced them they wanted one, and that it should be her!”) As always, though, we start off with the day's joyfully cool cosmic thing, the amazing discovery by the NEID Spectrograph at the WIYN telescope at Kitt Peak Observatory of a planet 9 times the mass of Earth orbiting a sun-like star 49 light years away with an orbital period of just 31 days. Melodie explains the precision of the measurement required to discover a planet at that distance, and shares one of her own recent discoveries using a technique called very-long-baseline interferometry (VLBI). In a groundbreaking effort she strung together 39 radio dishes across the northern hemisphere of Earth in a multi-observatory effort to create an Earth-sized telescope (similar to the technique that was used to create the first image of a black hole) and pointed it at a brown dwarf and measured its magnetic fields and radiation belts (like our Van Allen belts). For comparison, the effort was like measuring a pea perched on the Golden Gate Bridge in San Francisco while standing on the Statue of Liberty in NYC. The trio discusses the importance of the discovery of the Van Allen belts, and how that allowed us to plot trajectories that avoided the worst of that radiation for Apollo astronauts on their journeys to the Moon. For our first audience question, Ari from North Greene High School in Tennessee asks, “What is the percentage of possible exoplanets that are similar to the earth's atmosphere, placed in their solar system (within a similar area of their respective Goldilocks zone), gravity, etc.? And how long would it take to hypothetically get to them?” That turns out to be a very complicated question, and Melodie knows someone who has devoted her entire career to answering it. It's one of the questions that drove the creation of the James Webb Space Telescope and is the basis of the Drake Equation. The bottom line, though, is that we don't know yet, and until we find a rocky planet with an Earthlike atmosphere orbiting a sun-like star outside of our solar system, it will remain unanswerable. Next, Charles asks Melodie how she became an astronomer, especially since she'd always planned on being an architect. She even went to MIT to become one, but she missed studying physics, which she realized she truly loved. MIT had just finished constructing their Center for Theoretical Physics, and Melodie shares the story of how she convinced MIT to bend the rules and let switch her major to Physics while continuing to study architecture. When she attended a lecture by a grad student about galaxy clusters, and learned how you could back out the formation history of a cluster of galaxies by looking at the gradients of colors generated by starlight, she realized astronomy was a way to unlock the secrets of the universe. Our next question comes from Alex at North Greene: What are the conditions necessary for life in the universe? It's a question without an easy answer, but the conversation it spawns is worth your time to listen to. It leads Melodie to talk about her love of exploring the natural world and how she co-created a Wilderness Astronomy class. She's also a guide for off-trail, high route backpacking trips where you don't know what's coming next and you need to rely on your instincts, curiosity and bravery as you explore the world, and the universe, around you. If you'd like to know more about what Melodie is up to, she's not on social media but you can check out her website. You've also got an invitation to visit her at the Lowell Observatory for a personal tour! We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon. Credits for Images Used in this Episode: Dome of the 3.5m WIYN telescope at Kitt Peak – Credit Jörg Weingrill/ Creative Commons A cross section of Van Allen radiation belts – Credit By Booyabazooka at English Wikipedia - Transferred from en.wikipedia to Creative Commons / Public Domain The NASA Very Long Baseline Interferometry (VLBI) network – Credit Creative Commons / C. García-Miró, I. Sotuela, C.S. Jacobs, J.E. Clark, C.J. Naudet, L. A. White, R. Madde, M. Mercolino, D. Pazos, G. Bourda, P. Charlot, S. Horiuchi, P. Pope, L.G. Snedeker MIT Center for Theoretical Physics – Credit MIT News Galaxy cluster IDCS J1426. – Credit NASA The Cirque of the Towers, popular with high route backpackers. – Credit Kylir Horton / Creative Commons

In Folge 99 sind wir schon fast bei Folge 100. Oder eigentlich sind wir schon da, aber drüber reden wir nicht. Stattdessen über umfallende Sonden auf dem Mond, über kaputte Asteroiden und über den langen Flug der New Horizons, bis dahin wo es richtig staubig ist. Außerdem geht es um Moebius-Mathematik, um Pistolenschüsse auf Teleskope und den Zweck von Raumanzügen. Wenn ihr uns unterstützen wollt, könnt ihr das hier tun: https://www.paypal.com/paypalme/PodcastDasUniversum Oder hier: https://steadyhq.com/de/dasuniversum Oder hier: https://www.patreon.com/dasuniversum

Hun er egentlig Stasjonssjef for Kartverket på Ny-Ålesund, men vi døpte om tittelen hennes til Base Commander. Det høres tøffere ut. Susana Garcia Espada forklarer VLBI og livet på Ny-Ålesund. Opptaket blir avbrutt av en alarmtelefon, vi klatrer inne i radioteleskopene, og vi får svar på nøyaktig HVA signalet Kartverket tar ned fra kvasarene egentlig er.

Slipp 2 av 2, mandag 22. januar. Kartverket inviterte Romkapsel til Ny-Ålesund. Vi takket ja. De har tross alt store radioteleskop som lytter på kvasarer der! Sjefsingeniør for VLBI i Kartverket, Leif Morten Tangen forklarer hvorfor Kartverket har aktivitet på dette mørke, kalde stedet, og ikke minst hva VLBI er og hvorfor det er superviktig!

Hoy os invitamos a viajar de nuevo por el espacio exterior a la Tierra, en dirección a la constelación de Lira, hasta un objeto singular, una enana marrón, es decir, un objeto demasiado grande y caliente como para ser considerado un planeta pero mucho más pequeño y frío que una estrella. A pesar de encontrarse a más de 18 años luz de nosotros, Joan Climet, investigador de la Universidad de Valencia y de la Universidad Internacional de Valencia, y su equipo han logrado detectar en la enana marrón un cinturón de radiación como el que causa las auroras que se observan aquí y en otros planetas del Sistema Solar. Para obtener la imagen del cinturón de radiación, Climent y sus colegas utilizaron la señal de radio captada por la red europea de VLBI que combinó antenas de radio gigantes repartidas por todo el planeta, en España, Suecia, China o Sudáfrica. La detección de actividad auroral en un objeto tan distinto y tan distante como es una enana marrón, plantea retos y preguntas que Joan Climent comenta hoy en Hablando con Científicos.

Hoy os invitamos a viajar de nuevo por el espacio exterior a la Tierra, en dirección a la constelación de Lira, hasta un objeto singular, una enana marrón, es decir, un objeto demasiado grande y caliente como para ser considerado un planeta pero mucho más pequeño y frío que una estrella. A pesar de encontrarse a más de 18 años luz de nosotros, Joan Climet, investigador de la Universidad de Valencia y de la Universidad Internacional de Valencia, y su equipo han logrado detectar en la enana marrón un cinturón de radiación como el que causa las auroras que se observan aquí y en otros planetas del Sistema Solar. Para obtener la imagen del cinturón de radiación, Climent y sus colegas utilizaron la señal de radio captada por la red europea de VLBI que combinó antenas de radio gigantes repartidas por todo el planeta, en España, Suecia, China o Sudáfrica. La detección de actividad auroral en un objeto tan distinto y tan distante como es una enana marrón, plantea retos y preguntas que Joan Climent comenta hoy en Hablando con Científicos.

EAVN Astrometry toward the Extreme Outer Galaxy: Kinematic distance with the proper motion of G034 84-00 95 by Nobuyuki Sakai et al. on Thursday 24 November We aim to reveal the structure and kinematics of the Outer-Scutum-Centaurus (OSC) arm located on the far side of the Milky Way through very long baseline interferometry (VLBI) astrometry using KaVA, which is composed of KVN (Korean VLBI Network) and VERA (VLBI Exploration of Radio Astrometry). We report the proper motion of a 22 GHz H$_{2}$O maser source, which is associated with the star-forming region G034.84$-$00.95, to be ($mu_{alpha} rm{cos}delta$, $mu_{delta}$) = ($-$1.61$pm$0.18, $-$4.29$pm$0.16) mas yr$^{-1}$ in equatorial coordinates (J2000). We estimate the 2D kinematic distance to the source to be 18.6$pm$1.0 kpc, which is derived from the variance-weighted average of kinematic distances with LSR velocity and the Galactic-longitude component of the measured proper motion. Our result places the source in the OSC arm and implies that G034.84$-$00.95 is moving away from the Galactic plane with a vertical velocity of $-$38$pm$16 km s$^{-1}$. Since the H I supershell GS033+06$-$49 is located at a kinematic distance roughly equal to that of G034.84$-$00.95, it is expected that gas circulation occurs between the outer Galactic disk around G034.84$-$00.95 with a Galactocentric distance of 12.8$^{+1.0}_{-0.9}$ kpc and halo. We evaluate possible origins of the fast vertical motion of G034.84$-$00.95, which are (1) supernova explosions and (2) cloud collisions with the Galactic disk. However, neither of the possibilities are matched with the results of VLBI astrometry as well as spatial distributions of H II regions and H I gas. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.12534v1

EAVN Astrometry toward the Extreme Outer Galaxy: Kinematic distance with the proper motion of G034 84-00 95 by Nobuyuki Sakai et al. on Wednesday 23 November We aim to reveal the structure and kinematics of the Outer-Scutum-Centaurus (OSC) arm located on the far side of the Milky Way through very long baseline interferometry (VLBI) astrometry using KaVA, which is composed of KVN (Korean VLBI Network) and VERA (VLBI Exploration of Radio Astrometry). We report the proper motion of a 22 GHz H$_{2}$O maser source, which is associated with the star-forming region G034.84$-$00.95, to be ($mu_{alpha} rm{cos}delta$, $mu_{delta}$) = ($-$1.61$pm$0.18, $-$4.29$pm$0.16) mas yr$^{-1}$ in equatorial coordinates (J2000). We estimate the 2D kinematic distance to the source to be 18.6$pm$1.0 kpc, which is derived from the variance-weighted average of kinematic distances with LSR velocity and the Galactic-longitude component of the measured proper motion. Our result places the source in the OSC arm and implies that G034.84$-$00.95 is moving away from the Galactic plane with a vertical velocity of $-$38$pm$16 km s$^{-1}$. Since the H I supershell GS033+06$-$49 is located at a kinematic distance roughly equal to that of G034.84$-$00.95, it is expected that gas circulation occurs between the outer Galactic disk around G034.84$-$00.95 with a Galactocentric distance of 12.8$^{+1.0}_{-0.9}$ kpc and halo. We evaluate possible origins of the fast vertical motion of G034.84$-$00.95, which are (1) supernova explosions and (2) cloud collisions with the Galactic disk. However, neither of the possibilities are matched with the results of VLBI astrometry as well as spatial distributions of H II regions and H I gas. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.12534v1

3D Detection and Characterisation of ALMA Sources through Deep Learning by Michele Delli Veneri et al. on Tuesday 22 November We present a Deep-Learning (DL) pipeline developed for the detection and characterization of astronomical sources within simulated Atacama Large Millimeter/submillimeter Array (ALMA) data cubes. The pipeline is composed of six DL models: a Convolutional Autoencoder for source detection within the spatial domain of the integrated data cubes, a Recurrent Neural Network (RNN) for denoising and peak detection within the frequency domain, and four Residual Neural Networks (ResNets) for source characterization. The combination of spatial and frequency information improves completeness while decreasing spurious signal detection. To train and test the pipeline, we developed a simulation algorithm able to generate realistic ALMA observations, i.e. both sky model and dirty cubes. The algorithm simulates always a central source surrounded by fainter ones scattered within the cube. Some sources were spatially superimposed in order to test the pipeline deblending capabilities. The detection performances of the pipeline were compared to those of other methods and significant improvements in performances were achieved. Source morphologies are detected with subpixel accuracies obtaining mean residual errors of $10^{-3}$ pixel ($0.1$ mas) and $10^{-1}$ mJy/beam on positions and flux estimations, respectively. Projection angles and flux densities are also recovered within $10%$ of the true values for $80%$ and $73%$ of all sources in the test set, respectively. While our pipeline is fine-tuned for ALMA data, the technique is applicable to other interferometric observatories, as SKA, LOFAR, VLBI, and VLTI. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.11462v1

3D Detection and Characterisation of ALMA Sources through Deep Learning by Michele Delli Veneri et al. on Monday 21 November We present a Deep-Learning (DL) pipeline developed for the detection and characterization of astronomical sources within simulated Atacama Large Millimeter/submillimeter Array (ALMA) data cubes. The pipeline is composed of six DL models: a Convolutional Autoencoder for source detection within the spatial domain of the integrated data cubes, a Recurrent Neural Network (RNN) for denoising and peak detection within the frequency domain, and four Residual Neural Networks (ResNets) for source characterization. The combination of spatial and frequency information improves completeness while decreasing spurious signal detection. To train and test the pipeline, we developed a simulation algorithm able to generate realistic ALMA observations, i.e. both sky model and dirty cubes. The algorithm simulates always a central source surrounded by fainter ones scattered within the cube. Some sources were spatially superimposed in order to test the pipeline deblending capabilities. The detection performances of the pipeline were compared to those of other methods and significant improvements in performances were achieved. Source morphologies are detected with subpixel accuracies obtaining mean residual errors of $10^{-3}$ pixel ($0.1$ mas) and $10^{-1}$ mJy/beam on positions and flux estimations, respectively. Projection angles and flux densities are also recovered within $10%$ of the true values for $80%$ and $73%$ of all sources in the test set, respectively. While our pipeline is fine-tuned for ALMA data, the technique is applicable to other interferometric observatories, as SKA, LOFAR, VLBI, and VLTI. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.11462v1

Optical measurement of superluminal motion in the neutron-star merger GW170817 by Kunal P. Mooley et al. on Thursday 13 October The afterglow of the binary neutron star merger GW170817 gave evidence for a structured relativistic jet and a link between such mergers and short gamma-ray bursts. Superluminal motion, found using radio very long baseline interferometry (VLBI), together with the afterglow light curve provided constraints on the viewing angle (14-28 degrees), the opening angle of the jet core (less than about 5 degrees), and a modest limit on the initial Lorentz factor of the jet core (more than 4). Here we report on another superluminal motion measurement, at seven times the speed of light, leveraging Hubble Space Telescope precision astrometry and previous radio VLBI data of GW170817. We thereby obtain a unique measurement of the Lorentz factor of the wing of the structured jet, as well as substantially improved constraints on the viewing angle (19-25 degrees) and the initial Lorentz factor of the jet core (more than 40). arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.06568v1

Collimation of the relativistic jet in the quasar 3C 273 by Hiroki Okino et al. on Monday 10 October The collimation of relativistic jets launched from the vicinity of supermassive black holes (SMBHs) at the centers of active galactic nuclei (AGN) is one of the key questions to understand the nature of AGN jets. However, little is known about the detailed jet structure for AGN like quasars since very high angular resolutions are required to resolve these objects. We present very long baseline interferometry (VLBI) observations of the archetypical quasar 3C 273 at 86 GHz, performed with the Global Millimeter VLBI Array, for the first time including the Atacama Large Millimeter/submillimeter Array. Our observations achieve a high angular resolution down to $sim$60 ${rm mu}$as, resolving the innermost part of the jet ever on scales of $sim 10^5$ Schwarzschild radii. Our observations, including close-in-time High Sensitivity Array observations of 3C 273 at 15, 22, and 43 GHz, suggest that the inner jet collimates parabolically, while the outer jet expands conically, similar to jets from other nearby low luminosity AGN. We discovered the jet collimation break around $10^{7}$ Schwarzschild radii, providing the first compelling evidence for structural transition in a quasar jet. The location of the collimation break for 3C 273 is farther downstream the sphere of gravitational influence (SGI) from the central SMBH. With the results for other AGN jets, our results show that the end of the collimation zone in AGN jets is governed not only by the SGI of the SMBH but also by the more diverse properties of the central nuclei. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2112.12233v2

Distance estimates for AGB stars from parallax measurements by M. Andriantsaralaza et al. on Sunday 25 September Estimating the distances to asymptotic giant branch (AGB) stars using optical measurements of their parallaxes is not straightforward because of the large uncertainties introduced by their dusty envelopes, their large angular sizes, and their surface brightness variability. We compared the parallaxes from Gaia DR3 with parallaxes measured with maser observations with very long baseline interferometry (VLBI) to determine a statistical correction factor for the DR3 parallaxes using a sub-sample of 33 maser-emitting oxygen-rich nearby AGB stars. We found that the nominal errors on the Gaia DR3 parallaxes are underestimated by a factor of 5.44 for the brightest sources ($G

Radio Jet Proper-motion Analysis of Nine Distant Quasars above Redshift 3 5 by Yingkang Zhang et al. on Thursday 22 September Up to now, jet kinematic studies of radio quasars have barely reached beyond the redshift range at $z>3.5$. This significantly limits our knowledge of high-redshift jets, which can provide key information for understanding the jet nature and the growth of the black holes in the early Universe. In this paper, we selected 9 radio-loud quasars at $z>3.5$ which display milliarcsec-scale jet morphology. We provided evidence on the source nature by presenting high-resolution very long baseline interferometry (VLBI) images of the sample at 8.4~GHz frequency and making spectral index maps. We also consider Gaia optical positions that are available for 7 out of the 9 quasars, for a better identification of the jet components within the radio structures. We find that 6 sources can be classified as core--jet blazars. The remaining 3 objects are more likely young, jetted radio sources, compact symmetric objects. By including multi-epoch archival VLBI data, we also obtained jet component proper motions of the sample and estimated the jet kinematic and geometric parameters (Doppler factor, Lorentz factor, viewing angle). Our results show that at $z>3.5$, the jet apparent transverse speeds do not exceed 20 times the speed of light ($c$). This is consistent with earlier high-redshift quasar measurements in the literature and the tendency derived from low-redshift blazars that fast jet speeds ($>40,c$) only occur at low redshifts. The results from this paper contribute to the understanding of the cosmological evolution of radio AGN. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.10760v1

Software and techniques for VLBI data processing and analysis by Michael Janssen et al. on Wednesday 14 September Very-long-baseline interferometry (VLBI) is a challenging observational technique, which requires in-depth knowledge about radio telescope instrumentation, interferometry, and the handling of noisy data. The reduction of the raw data is mostly left to the scientists and demands the use of complex algorithms implemented in comprehensive software packages. The correct application of these algorithms necessitates a good understanding of the underlying techniques and physics that are at play. The verification of the processed data produced by the algorithms demands a thorough understanding of the underlying interferometric VLBI measurements. This review describes the latest techniques and algorithms that scientists should know about when analyzing VLBI data. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.06115v1

Software and techniques for VLBI data processing and analysis by Michael Janssen et al. on Wednesday 14 September Very-long-baseline interferometry (VLBI) is a challenging observational technique, which requires in-depth knowledge about radio telescope instrumentation, interferometry, and the handling of noisy data. The reduction of the raw data is mostly left to the scientists and demands the use of complex algorithms implemented in comprehensive software packages. The correct application of these algorithms necessitates a good understanding of the underlying techniques and physics that are at play. The verification of the processed data produced by the algorithms demands a thorough understanding of the underlying interferometric VLBI measurements. This review describes the latest techniques and algorithms that scientists should know about when analyzing VLBI data. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.06115v1

Distance estimates for AGB stars from parallax measurements by M. Andriantsaralaza et al. on Sunday 11 September Estimating the distances to asymptotic giant branch (AGB) stars using optical measurements of their parallaxes is not straightforward because of the large uncertainties introduced by their dusty envelopes, their large angular sizes, and their surface brightness variability. We compared the parallaxes from Gaia DR3 with parallaxes measured with maser observations with very long baseline interferometry (VLBI) to determine a statistical correction factor for the DR3 parallaxes using a sub-sample of 33 maser-emitting oxygen-rich nearby AGB stars. We found that the nominal errors on the Gaia DR3 parallaxes are underestimated by a factor of 5.44 for the brightest sources ($G

Distance estimates for AGB stars from parallax measurements by M. Andriantsaralaza et al. on Sunday 11 September Estimating the distances to asymptotic giant branch (AGB) stars using optical measurements of their parallaxes is not straightforward because of the large uncertainties introduced by their dusty envelopes, their large angular sizes, and their surface brightness variability. We compared the parallaxes from Gaia DR3 with parallaxes measured with maser observations with very long baseline interferometry (VLBI) to determine a statistical correction factor for the DR3 parallaxes using a sub-sample of 33 maser-emitting oxygen-rich nearby AGB stars. We found that the nominal errors on the Gaia DR3 parallaxes are underestimated by a factor of 5.44 for the brightest sources ($G

喜歡張大春主持的「聽說張大春」嗎？歡迎小額贊助我們，讓我們繼續產出優質節目＞https://bit.ly/3dzJX7V 主持人：張大春 來賓：前國立自然科學博物館館長 孫維新 主題：事件視界望遠鏡 Event Horizon Telescope （EHT） 黑洞觀測計畫「事件視界望遠鏡」(Event Horizon Telescope, EHT)，黑洞觀測計畫是一個以觀測星系中央超大質量黑洞為主要目標的計畫，也是全球性的大型望遠鏡陣列計畫。計劃以特長基線干涉技術（Very-long-baseline interferometry, VLBI）協調世界各地的電波望遠鏡，使許多相隔數十萬公里的獨立天線能互相協調、同時觀測同一目標並記錄下數據，形成口徑等同地球直徑的虛擬望遠鏡，期望藉此檢驗愛因斯坦廣義相對論在黑洞附近的強重力場下是否會產生偏差、研究黑洞的吸積盤及噴流、探討事件視界存在與否。 EHT不僅要證明黑洞存在與否，還包括去了解黑洞和落入黑洞中的周圍氣體。EHT的觀測波長設定於1.33毫米，並預計於未來提升至能更精細觀測的0.87毫米。EHT的觀測目標主要為位於南半天球、銀河系中央的超大質量黑洞人馬座A*以及位於北天球的橢圓星系M87星系中央的超大質量黑洞，其中人馬座A*在地球天空中佔的盤面較大，而Ｍ87的黑洞則以擁有一道長達5,000光年的噴流為著名特色。 相較於傳統的可見光望遠鏡，事件視界望遠鏡觀察的是人眼不可見的電波，波長處於毫米／次毫米範圍，主要用來偵測星際塵埃的熱輻射，或是星際雲氣的分子譜線。2019年4月10日，事件視界望遠鏡合作組織發布了最新的觀測結果，成功捕捉到超大質量黑洞M87的影像，這是第一次正式的黑洞「視覺證據」。這張黑洞照片於2017年4月5日至11日之間的4個晚上，由7個遍佈全球(夏威夷、美洲、歐洲)的電波望遠鏡共同觀測所得到。這個影像有兩個重點，一是中間的黑洞陰影（形狀與黑洞自身的旋轉有關），二是不對稱的光暈（稱為光子環，不對稱乃黑洞陰影所致）；事件視界便隱藏在黑洞陰影之內。 ----- ▍聽更多：https://flow.page/thehearsay ▍粉絲團：https://www.facebook.com/TheHearSayChannel ▍合作贊助：thehearsaytw@gmail.com Powered by Firstory Hosting

En el Observatorio Astronómico de Yebes, que hoy visitamos guiados por su director, el astrónomo Pablo de Vicente, se observa al Universo con grandes antenas capaces de captar las emisiones de radio procedentes de las regiones más energéticas o frías del Universo. Además de las investigaciones astronómicas, el radiotelescopio de 40 metros de Yebes, que participa en redes de Interferometría de Larga Base (VLBI), se utiliza para “Geodesia Espacial”. Este tipo de redes permiten calcular, con precisión milimétrica, la distancia entre dos radiotelescopios separados miles de kilómetros, con estos datos es posible detectar el movimiento de las placas tectónicas, las variaciones del campo gravitatorio y de la rotación terrestre y otras medidas geodésicas. Estas observaciones han permitido medir con un una precisión de centímetros la posición del robot InsSight de la NASA en Marte.

En el Observatorio Astronómico de Yebes, que hoy visitamos guiados por su director, el astrónomo Pablo de Vicente, se observa al Universo con grandes antenas capaces de captar las emisiones de radio procedentes de las regiones más energéticas o frías del Universo. Además de las investigaciones astronómicas, el radiotelescopio de 40 metros de Yebes, que participa en redes de Interferometría de Larga Base (VLBI), se utiliza para “Geodesia Espacial”. Este tipo de redes permiten calcular, con precisión milimétrica, la distancia entre dos radiotelescopios separados miles de kilómetros, con estos datos es posible detectar el movimiento de las placas tectónicas, las variaciones del campo gravitatorio y de la rotación terrestre y otras medidas geodésicas. Estas observaciones han permitido medir con un una precisión de centímetros la posición del robot InsSight de la NASA en Marte.

Highest resolution Event Horizon Telescope (EHT) observations will probably soon tell us more about the supermassive black hole at the Galactic Centre (Sgr A*) and the cores of active galactic nuclei (AGN). It might also help to clarify the long-standing question whether the central massive objects in AGN are instead close pairs of black holes. Mergers of supermassive black hole pairs would provide the strongest gravitational wave signals. I will present examples of how we identify potential close binary black hole candidates based on the combined analysis of high resolution radio interferometric (VLBI) observations and multi- wavelength data. I will also provide an outlook on the scientific prospects with regard to future EHT-observations.

UFO sighting: Space Shuttle photo sparks claims of NASA alien conspiracy '100% proof' Link: https://www.express.co.uk/news/weird/1214569/ufo-sighting-space-shuttle-photo-nasa-alien-life-conspiracy-theory UFO watcher Scott Waring has found ‘100 percent proof' of an alien craft orbiting Earth, in a photograph shot from NASA's Discovery Space Shuttle, he says. The self-proclaimed alien life expert took to his etdatabase.com blog to speculate about the oddly-shaped anomaly he stumbled across. He said: “I was searching through NASA archive photos and saw this beautiful Moon photo taken from the Shuttle Discovery. “I didn't think I would find anything at the time, just thought it was a beautiful photo. “I enlarged it and put it into auto focus and found something amazing. I have never ever reported a UFO of this shape Image link: https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=STS039&roll=75&frame=32 He added: “And yet, there it its, above the sunset clouds in earths orbit on a NASA website. “This is 100 percent proof of the existence of intelligent aliens watching over earth.” This unusual anomaly, only visible after zooming into the image, was shot during the Space Shuttle Discovery STS 39 mission. This mission took place in April 1991, while the image was taken with a high quality Hasselblad camera. The anomaly is found only at the corner of a stunning portrait of the Moon as seen from space. China's Huge, Alien-Hunting Radio Telescope Is Finishing Its Testing Phase Link: https://www.space.com/china-fast-radio-telescope-finishing-alien-search-tests.html The Five-hundred-meter Aperture Spherical Telescope has hit the ground running. China's giant, alien-hunting radio telescope is finishing its testing-and-commissioning phase, which has occurred over the past three years. Located in southern China's Guizhou province, the Five-hundred-meter Aperture Spherical Telescope (FAST) began these trial operations in September 2016. China Central Television (CCTV) reports that, so far, FAST has detected and identified 99 rapidly spinning neutron stars known as pulsars, more than 30 of which are especially fast-rotating millisecond pulsars. The search for extraterrestrial life and other scientific targets is also underway. "In the process of observing signals from celestial bodies, we also collect signals that might be emitted by humans or extraterrestrial intelligence," Zhu Ming, director of the scientific observation and data division at the FAST operations and development center, explained in a recent CCTV video. "However, this is a huge amount of work, since most signals we see — 99% of them — are various noises, so we need to take our time to identify the signals we want in the noises," Zhu said. The FAST website lists the following science objectives of the radio telescope:[36] •Large scale neutral hydrogen survey •Pulsar observations •Leading the international very long baseline interferometry (VLBI) network •Detection of interstellar molecules •Detecting interstellar communication signals (Search for extraterrestrial intelligence) •Pulsar timing arrays[37] The FAST telescope joined the Breakthrough Listen SETI project in October 2016 to search for intelligent extraterrestrial communications in the Universe.[38] Show Stuff The Dark Horde, LLC – http://www.thedarkhorde.com Twitter @DarkHorde or https://twitter.com/HordeDark TeePublic Store - Get your UBR goodies today! http://tee.pub/lic/2GQuXxn79dg UBR Truth Seekers Facebook Group: https://www.facebook.com/groups/216706068856746 UFO Buster Radio: https://www.facebook.com/UFOBusterRadio YouTube Channel: https://www.youtube.com/channel/UCggl8-aPBDo7wXJQ43TiluA To contact Manny: manny@ufobusterradio.com, or on Twitter @ufobusterradio Call the show anytime at (972) 290-1329 and leave us a message with your point of view, UFO sighting, and ghostly experiences or join the discussion on www.ufobusterradio.com For Skype Users: bosscrawler

UFO sighting: Space Shuttle photo sparks claims of NASA alien conspiracy '100% proof' Link: https://www.express.co.uk/news/weird/1214569/ufo-sighting-space-shuttle-photo-nasa-alien-life-conspiracy-theory UFO watcher Scott Waring has found ‘100 percent proof' of an alien craft orbiting Earth, in a photograph shot from NASA's Discovery Space Shuttle, he says. The self-proclaimed alien life expert took to his etdatabase.com blog to speculate about the oddly-shaped anomaly he stumbled across. He said: “I was searching through NASA archive photos and saw this beautiful Moon photo taken from the Shuttle Discovery. “I didn't think I would find anything at the time, just thought it was a beautiful photo. “I enlarged it and put it into auto focus and found something amazing. I have never ever reported a UFO of this shape Image link: https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=STS039&roll=75&frame=32 He added: “And yet, there it its, above the sunset clouds in earths orbit on a NASA website. “This is 100 percent proof of the existence of intelligent aliens watching over earth.” This unusual anomaly, only visible after zooming into the image, was shot during the Space Shuttle Discovery STS 39 mission. This mission took place in April 1991, while the image was taken with a high quality Hasselblad camera. The anomaly is found only at the corner of a stunning portrait of the Moon as seen from space. China's Huge, Alien-Hunting Radio Telescope Is Finishing Its Testing Phase Link: https://www.space.com/china-fast-radio-telescope-finishing-alien-search-tests.html The Five-hundred-meter Aperture Spherical Telescope has hit the ground running. China's giant, alien-hunting radio telescope is finishing its testing-and-commissioning phase, which has occurred over the past three years. Located in southern China's Guizhou province, the Five-hundred-meter Aperture Spherical Telescope (FAST) began these trial operations in September 2016. China Central Television (CCTV) reports that, so far, FAST has detected and identified 99 rapidly spinning neutron stars known as pulsars, more than 30 of which are especially fast-rotating millisecond pulsars. The search for extraterrestrial life and other scientific targets is also underway. "In the process of observing signals from celestial bodies, we also collect signals that might be emitted by humans or extraterrestrial intelligence," Zhu Ming, director of the scientific observation and data division at the FAST operations and development center, explained in a recent CCTV video. "However, this is a huge amount of work, since most signals we see — 99% of them — are various noises, so we need to take our time to identify the signals we want in the noises," Zhu said. The FAST website lists the following science objectives of the radio telescope:[36] •Large scale neutral hydrogen survey •Pulsar observations •Leading the international very long baseline interferometry (VLBI) network •Detection of interstellar molecules •Detecting interstellar communication signals (Search for extraterrestrial intelligence) •Pulsar timing arrays[37] The FAST telescope joined the Breakthrough Listen SETI project in October 2016 to search for intelligent extraterrestrial communications in the Universe.[38] Show Stuff The Dark Horde, LLC – http://www.thedarkhorde.com Twitter @DarkHorde or https://twitter.com/HordeDark TeePublic Store - Get your UBR goodies today! http://tee.pub/lic/2GQuXxn79dg UBR Truth Seekers Facebook Group: https://www.facebook.com/groups/216706068856746 UFO Buster Radio: https://www.facebook.com/UFOBusterRadio YouTube Channel: https://www.youtube.com/channel/UCggl8-aPBDo7wXJQ43TiluA To contact Manny: manny@ufobusterradio.com, or on Twitter @ufobusterradio Call the show anytime at (972) 290-1329 and leave us a message with your point of view, UFO sighting, and ghostly experiences or join the discussion on www.ufobusterradio.com For Skype Users: bosscrawler

Jeb Card and Blake Smith are joined by "spooky geologist" Sharon Hill to talk about this classic season one episode of In Search Of... that considers various methods to predict earthquakes, and what we might expect if a large quake hits the San Francisco area. Watch this episode of In Search Of... on YouTube. Nimoy Fashion - once again speaking to us from a Los Angeles rooftop. Around the 9 min mark, we mistakenly say the Bay of Fundy is in Newfoundland. Nope - it's between Nova Scotia and New Brunswick. (Does everything in Canada have to have "new" in its name??) Thanks to Stephanie J. Lahey for this correction! 1964 Alaska Earthquake (Wikipedia) 2011 Earthquake/Tsunami (Disturbing Footage) 1936 Hollywood Movie about San Francisco Earthquake Tallest tsunami ever recorded.  VLBI - Very Long Baseline Interferometry   Quasars for VLBI type research (NY Times) 1989 Double-Decker Collapse (Wikipedia) Clips from 2015 San Andreas starring The Rock Listener Darren Bennett advises us that the 1982 "Syzygy" disaster referenced in the show as The Jupiter Effect.  It was written by John Gribbin, a science writer who has apparently subsequently regretted it. (He's still alive and still writing science books - but tried to distance himself from his own book in a July 1980 issue of New Scientist.)    

Wenn man das Universum richtig gut sehen will, dann braucht man Teleskope mit Löchern. Die Technik nennt sich "Interferometrie". Und sie hat die Aufnahme des ersten Bilds eines schwarzen Lochs möglich gemacht. Wie das geht erfahrt ihr in der neuen Folge des Sternengeschichten-Podcast.

Marina, Jordan et Alexandre, en stage chez YouTalk, vous présentent leur première émission liée à notre thème du mois : l'espace. Avec eux, nous allons partir pour un voyage vers les étoiles, ou plutôt les trous noirs. Dans cette émission nous allons vous parler de leur découverte, de leur histoire du début jusqu’à nos jours, ainsi que des techniques utilisées par les chercheurs pour nous faire voir l’invisible et faire d'une fiction une réalité. Réalisée par : Marina , Alexandre et Jordan Lien(s) utile(s) : https://www.futura-sciences.com/sciences/definitions/astronomie-disque-accretion-3819/ https://www.lci.fr/sciences/video-explore-le-trou-noir-c-est-quoi-un-phenomene-dont-on-n-a-pas-fini-d-epuiser-les-mysteres-einstein-hawking-supermassif-2082850.html https://fr.wikipedia.org/wiki/Event_Horizon_Telescope https://fr.wikipedia.org/wiki/Trou_noir https://fr.wikipedia.org/wiki/Interf%C3%A9rom%C3%A9trie_%C3%A0_tr%C3%A8s_longue_base#VLBI_spatiale https://www.ouest-france.fr/sciences/astronomie/qui-est-katie-bouman-la-jeune-scientifique-derriere-la-photo-historique-du-trou-noir-6305628 Pour nous suivre : Facebook → facebook.com/YouTalkMLT Instagram → instagram.com/youtalkmlt Twitter → twitter.com/YouTalkMLT Soundcloud → soundcloud.com/youtalkmlt Itunes → itunes.apple.com/fr/podcast/youtalk/id1446573183 Youtube → youtube.com/channel/UCWtYii3530Yl5IIXcgEeciA Mission locale Technowest → mltechnowest.com

Today we are speaking with Dr Hayley Bignall. Hayley is an astrophysicist for Australia’s CSIRO in their Astronomy & Space Science Division. After her studies, she spent 5 yrs working at the Joint Institute for VLBI in Europe and is now based in Perth, Australia. After spending about 7 years at The International Centre for Radio Astronomy Research (ICRAR) at Curtin University, she joined CSIRO in 2016. Hayley explains how a team she works with have made some fabulous discoveries about blazars and quasars and ‘scintillations’ in intergalactic space. Dr Ian Musgrave in ‘What’s up Doc’ tells us what to look for in the morning and evening skies and explains how an occultation project lead to the discovery of a comet with a binary cross-section In the News: Amazing new gravity wave source could be visible neutron stars rather then ‘invisible’ black holes.

Transcript: Hundreds of radio galaxies have been found, studied, and identified using synthesis radio telescopes like the Very Large Array. A typical radio galaxy has a radio morphology with an intense and compact core of radio emission. On small scales the core can only be resolved with VLBI techniques with milliarcsecond resolution and in fact is about the size of the solar system. Emerging from the core in two directions are radio jets. These jets can extend beyond the distance of the galaxy itself which is typical of an elliptical galaxy. On the largest scales these jets connect with diffuse, fuzzy lobes of radio emission. The lobes can extend for millions of lightyears into the intergalactic medium.

Transcript -- How do radio astronomers see jets far outside our galaxy? Introducing the MERLIN array in the UK and the VLA in New Mexico.

Transcript -- How do radio astronomers see jets far outside our galaxy? Introducing the MERLIN array in the UK and the VLA in New Mexico.

How do radio astronomers see jets far outside our galaxy? Introducing the MERLIN array in the UK and the VLA in New Mexico.

How do radio astronomers see jets far outside our galaxy? Introducing the MERLIN array in the UK and the VLA in New Mexico.

Radio telescopes must be very large in size to achieve the same resolution as optical telescopes. The only way to do this is by coupling two or more of them, the further apart the better, and to analyse their combined signals. An interferometer is a system which can avoid increased expenses due to the large size of the receiver. It consists of two or more elements of large antennae. By connecting them in a special fashion, it is possible to artificially create a larger telescope. The European hub for what is called Very Long Baseline Interferometry (VLBI) is situated in Dwingeloo in the Netherlands, at the Joint Institute for VLBI in Europe, JIVE.ESApod video programme

昨年11月30日の最期の運用をもって引退した、電波天文衛星「はるか」のプロジェクトマネージャー平林久教授にお話を伺いました。大型展開アンテナ、 VLBI干渉実験などさまざまな工学実験を重ねて、スペースVLBI観測を実現し、大きな国際共同によるVSOP計画の中心となった衛星です。 解説者：宇宙航空研究開発機構　宇宙科学研究本部 　　　　平林久 「はるか」プロジェクトマネージャー 　　　　（宇宙情報・エネルギー工学研究系　教授・工学博士） 聞き手：科学ジャーナリスト　寺門和夫

In this month's show we find out about gamma ray bursts with Paul O'Brien, take a tour of the Mt. John Observatory in New Zealand, catch up on NASA's Stardust mission and discover what goes on at the Joint Institute for VLBI in Europe (JIVE). We pose all your difficult questions to Tim O'Brien and find out what you can see in the night sky during April. As a special treat we also get Ian and Tim's commentary from the 29th March total solar eclipse.

In this month's show we find out about gamma ray bursts with Paul O'Brien, take a tour of the Mt. John Observatory in New Zealand, catch up on NASA's Stardust mission and discover what goes on at the Joint Institute for VLBI in Europe (JIVE). We pose all your difficult questions to Tim O'Brien and find out what you can see in the night sky during April. As a special treat we also get Ian and Tim's commentary from the 29th March total solar eclipse.