NASA’s Webb solar array reconnects to the telescope One kilowatt is about what it takes to heat up some leftovers in a microwave—or to power the largest and most technically advanced telescope ever built. Thanks to its solar array, NASA’s James Webb Space Telescope will stay energy-efficient more than 1 million miles (1.5 million kilometers) from Earth. phys.org Go to SourceRead More →
Beyond “Fermi’s Paradox” VII: The Planetarium Hypothesis Welcome back to our Fermi Paradox series, where we take a look at possible resolutions to Enrico Fermi’s famous question, “Where Is Everybody?” Today, we examine the possibility that we can’t see them because they have us all inside a massive simulation! In 1950, Italian-American physicist Enrico Fermi sat down to lunch with some of … Continue reading “Beyond “Fermi’s Paradox” VII: The Planetarium Hypothesis” The post Beyond “Fermi’s Paradox” VII: The Planetarium Hypothesis appeared first on Universe Today. Universe Today Go to SourceRead More →
Hubble maps giant halo around Andromeda Galaxy In a landmark study, scientists using NASA’s Hubble Space Telescope have mapped the immense envelope of gas, called a halo, surrounding the Andromeda galaxy, our nearest large galactic neighbor. Scientists were surprised to find that this tenuous, nearly invisible halo of diffuse plasma extends 1.3 million light-years from the galaxy—about halfway to our Milky Way—and as far as 2 million light-years in some directions. This means that Andromeda’s halo is already bumping into the halo of our own galaxy. phys.org Go to SourceRead More →
New study questions decades of research on the evolution of spiral galaxies Previous studies on the formation and evolution of spiral galaxies might have been based on an incorrect assumption, suggests a team of researchers of Instituto de Astrofísica e Ciências do Espaço (IA). phys.org Go to SourceRead More →
Comet NEOWISE Was Spiraling and Spinning as it Passed by Earth Earlier this week, we shared an image of Comet NEOWISE (C/2020 F3) taken by the Hubble Space Telescope. And now, here are a group of images from the 8.1-metre Gemini North telescope in Hawaii. Like Hubble, Gemini North focused in on the comet’s nucleus and coma, instead of its stunning, gossamer tails. But Gemini zoomed … Continue reading “Comet NEOWISE Was Spiraling and Spinning as it Passed by Earth” The post Comet NEOWISE Was Spiraling and Spinning as it Passed by Earth appeared first on Universe Today. Universe Today Go to SourceRead More →
Did a supernova cause the Devonian mass extinction event? 359 million years ago the Earth suffered one of its worst extinction events, and a team of researchers at the University of Illinois think that it might be caused by a series of supernova explosions no more than 35 light years away. Every once in a while something disastrous happens to life on Earth. The … Continue reading “Did a supernova cause the Devonian mass extinction event?” The post Did a supernova cause the Devonian mass extinction event? appeared first on Universe Today. Universe Today Go to SourceRead More →
Gas reaches young stars along magnetic field lines Astronomers have used the GRAVITY instrument to study the immediate vicinity of a young star in more detail than ever before. Their observations confirm a thirty-year-old theory about the growth of young stars: the magnetic field produced by the star itself directs material from a surrounding accretion disk of gas and dust onto its surface. The results, published today in the journal Nature, help astronomers to better understand how stars like our Sun are formed and how Earth-like planets are produced from the disks surrounding these stellar babies. phys.org Go to SourceRead More →
There Could Be More Rogue Planets Than Stars in the Milky Way. Here’s How Nancy Grace Will Find Them Rogue planets are notoriously hard to detect, unless you’re the Jedi in an Extended Universe novel. So far we have only been able to discover a handful, but estimates range from a few billion to a trillion solitary planets floating through the galaxy. NASA hopes to dramatically increase the number we’ve detected, and thereby better … Continue reading “There Could Be More Rogue Planets Than Stars in the Milky Way. Here’s How Nancy Grace Will Find Them” The post There Could Be More Rogue Planets ThanRead More →
Maunakea observatories discover three pairs of merging supermassive black holes A cosmic dance between two merging galaxies, each one containing a supermassive black hole that’s rapidly feeding on so much material it creates a phenomenon known as a quasar, is a rare find. phys.org Go to SourceRead More →
Continuous infrared winds discovered during the eruption of a stellar mass black hole A team of researchers from the Instituto de Astrofísica de Canarias (IAC) has, for the first time, detected constant infrared emission from winds produced during the eruption of a black hole in an X-ray binary. phys.org Go to SourceRead More →
An Excess of Globular Clusters in UDGs Formed Through Tidal Heating. (arXiv:2008.11205v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Carleton_T/0/1/0/all/0/1">Timothy Carleton</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Guo_Y/0/1/0/all/0/1">Yicheng Guo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Munshi_F/0/1/0/all/0/1">Ferah Munshi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tremmel_M/0/1/0/all/0/1">Michael Tremmel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wright_A/0/1/0/all/0/1">Anna Wright</a> To investigate the origin of elevated globular cluster abundances observed around Ultra- Diffuse Galaxies (UDGs), we simulate globular cluster populations hosted by UDGs formed through tidal heating. Specifically, globular cluster (GC) formation is modeled as occurring in regions of dense star formation. Because star-formation-rate-densities are higher at high redshift, dwarf galaxies in massive galaxy clusters, which formed most of their stars at high redshift, form a large fraction of their stars in globular clusters. Given that UDGsRead More →
Understanding the HERA Phase I receiver system with simulations and its impact on the detectability of the EoR delay power spectrum. (arXiv:1908.02383v2 [astro-ph.IM] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Fagnoni_N/0/1/0/all/0/1">Nicolas Fagnoni</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Acedo_E/0/1/0/all/0/1">Eloy de Lera Acedo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+DeBoer_D/0/1/0/all/0/1">David R. DeBoer</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Abdurashidova_Z/0/1/0/all/0/1">Zara Abdurashidova</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Aguirre_J/0/1/0/all/0/1">James E. Aguirre</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Alexander_P/0/1/0/all/0/1">Paul Alexander</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ali_Z/0/1/0/all/0/1">Zaki S. Ali</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Balfour_Y/0/1/0/all/0/1">Yanga Balfour</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Beardsley_A/0/1/0/all/0/1">Adam P. Beardsley</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bernardi_G/0/1/0/all/0/1">Gianni Bernardi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Billings_T/0/1/0/all/0/1">Tashalee S. Billings</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bowman_J/0/1/0/all/0/1">Judd D. Bowman</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bradley_R/0/1/0/all/0/1">Richard F. Bradley</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bull_P/0/1/0/all/0/1">Phil Bull</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Burba_J/0/1/0/all/0/1">Jacob Burba</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Carilli_C/0/1/0/all/0/1">Chris L. Carilli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Cheng_C/0/1/0/all/0/1">Carina Cheng</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dexter_M/0/1/0/all/0/1">Matt Dexter</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dillon_J/0/1/0/all/0/1">Joshua S. Dillon</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ewall_Wice_A/0/1/0/all/0/1">Aaron Ewall-Wice</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fritz_R/0/1/0/all/0/1">Randall Fritz</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Furlanetto_S/0/1/0/all/0/1">Steve R. Furlanetto</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gale_Sides_K/0/1/0/all/0/1">Kingsley Gale-Sides</a>,Read More →
Structure Formation Models Weaken Limits on WIMP Dark Matter from Dwarf Spheroidal Galaxies. (arXiv:2002.11956v2 [astro-ph.CO] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Ando_S/0/1/0/all/0/1">Shin'ichiro Ando</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Geringer_Sameth_A/0/1/0/all/0/1">Alex Geringer-Sameth</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hiroshima_N/0/1/0/all/0/1">Nagisa Hiroshima</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hoof_S/0/1/0/all/0/1">Sebastian Hoof</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Trotta_R/0/1/0/all/0/1">Roberto Trotta</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Walker_M/0/1/0/all/0/1">Matthew G. Walker</a> Dwarf spheroidal galaxies that form in halo substructures provide stringent constraints on dark matter annihilation. Many ultrafaint dwarfs discovered with modern surveys contribute significantly to these constraints. At present, because of the lack of abundant stellar kinematic data for the ultrafaints, non-informative prior assumptions are usually made for the parameters of the density profiles. Based on semi-analytic models of dark matter subhalos and their connection to satellite galaxies, we presentRead More →
Detecting and Characterizing Young Quasars I: Systemic Redshifts and Proximity Zones Measurements. (arXiv:2002.01811v3 [astro-ph.GA] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Eilers_A/0/1/0/all/0/1">Anna-Christina Eilers</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hennawi_J/0/1/0/all/0/1">Joseph F. Hennawi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Decarli_R/0/1/0/all/0/1">Roberto Decarli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Davies_F/0/1/0/all/0/1">Frederick B. Davies</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Venemans_B/0/1/0/all/0/1">Bram Venemans</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Walter_F/0/1/0/all/0/1">Fabian Walter</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Banados_E/0/1/0/all/0/1">Eduardo Bañados</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fan_X/0/1/0/all/0/1">Xiaohui Fan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Farina_E/0/1/0/all/0/1">Emanuele P. Farina</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mazzucchelli_C/0/1/0/all/0/1">Chiara Mazzucchelli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Novak_M/0/1/0/all/0/1">Mladen Novak</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schindler_J/0/1/0/all/0/1">Jan-Torge Schindler</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Simcoe_R/0/1/0/all/0/1">Robert A. Simcoe</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wang_F/0/1/0/all/0/1">Feige Wang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Yang_J/0/1/0/all/0/1">Jinyi Yang</a> In a multi-wavelength survey of $13$ quasars at $5.8lesssim zlesssim6.5$, that were pre-selected to be potentially young, we find five objects with extremely small proximity zone sizes that may imply UV-luminous quasar lifetimes of $lesssim 100,000$ years. Proximity zones are regionsRead More →
Anti-Deuterons and Anti-Helium Nuclei from Annihilating Dark Matter. (arXiv:2001.08749v2 [astro-ph.HE] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Cholis_I/0/1/0/all/0/1">Ilias Cholis</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Linden_T/0/1/0/all/0/1">Tim Linden</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hooper_D/0/1/0/all/0/1">Dan Hooper</a> Recent studies of the cosmic-ray antiproton-to-proton ratio have identified an excess of $sim$10-20 GeV antiprotons relative to the predictions of standard astrophysical models. Intriguingly, the properties of this excess are consistent with the same range of dark matter models that can account for the long-standing excess of $gamma$-rays observed from the Galactic Center. Such dark matter candidates can also produce significant fluxes of anti-deuterium and anti-helium nuclei. Here we study the production and transport of such particles, both from astrophysical processes as well as fromRead More →
Measurement of the B-band Galaxy Luminosity Function with Approximate Bayesian Computation. (arXiv:2001.07727v2 [astro-ph.GA] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Tortorelli_L/0/1/0/all/0/1">Luca Tortorelli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fagioli_M/0/1/0/all/0/1">Martina Fagioli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Herbel_J/0/1/0/all/0/1">Jörg Herbel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Amara_A/0/1/0/all/0/1">Adam Amara</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kacprzak_T/0/1/0/all/0/1">Tomasz Kacprzak</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Refregier_A/0/1/0/all/0/1">Alexandre Refregier</a> The galaxy Luminosity Function (LF) is a key observable for galaxy formation, evolution studies and for cosmology. In this work, we propose a novel technique to forward model wide-field broad-band galaxy surveys using the fast image simulator UFig and measure the LF of galaxies in the B-band. We use Approximate Bayesian Computation (ABC) to constrain the galaxy population model parameters of the simulations and match data from CFHTLS. We define a number ofRead More →
Artificial neural network subgrid models of 2-D compressible magnetohydrodynamic turbulence. (arXiv:1912.11073v2 [physics.comp-ph] UPDATED) <a href="http://arxiv.org/find/physics/1/au:+Rosofsky_S/0/1/0/all/0/1">Shawn G. Rosofsky</a>, <a href="http://arxiv.org/find/physics/1/au:+Huerta_E/0/1/0/all/0/1">E. A. Huerta</a> We explore the suitability of deep learning to capture the physics of subgrid-scale ideal magnetohydrodynamics turbulence of 2-D simulations of the magnetized Kelvin-Helmholtz instability. We produce simulations at different resolutions to systematically quantify the performance of neural network models to reproduce the physics of these complex simulations. We compare the performance of our neural networks with gradient models, which are extensively used in the extensively in the magnetohydrodynamic literature. Our findings indicate that neural networks significantly outperform gradient models at reproducing the effects ofRead More →
ESA Voyage 2050 white paper — GrailQuest: hunting for Atoms of Space and Time hidden in the wrinkle of Space-Time. (arXiv:1911.02154v2 [astro-ph.IM] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Burderi_L/0/1/0/all/0/1">L. Burderi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sanna_A/0/1/0/all/0/1">A. Sanna</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Salvo_T/0/1/0/all/0/1">T. Di Salvo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Amati_L/0/1/0/all/0/1">L. Amati</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Amelino_Camelia_G/0/1/0/all/0/1">G. Amelino-Camelia</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Branchesi_M/0/1/0/all/0/1">M. Branchesi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Capozziello_S/0/1/0/all/0/1">S. Capozziello</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Coccia_E/0/1/0/all/0/1">E. Coccia</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Colpi_M/0/1/0/all/0/1">M. Colpi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Costa_E/0/1/0/all/0/1">E. Costa</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+DAmico_N/0/1/0/all/0/1">N. D'Amico</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bernardis_P/0/1/0/all/0/1">P. De Bernardis</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Laurentis_M/0/1/0/all/0/1">M. De Laurentis</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Valle_M/0/1/0/all/0/1">M. Della Valle</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Falcke_H/0/1/0/all/0/1">H. Falcke</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Feroci_M/0/1/0/all/0/1">M. Feroci</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fiore_F/0/1/0/all/0/1">F. Fiore</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Frontera_F/0/1/0/all/0/1">F. Frontera</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gambino_A/0/1/0/all/0/1">A. F. Gambino</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ghisellini_G/0/1/0/all/0/1">G. Ghisellini</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hurley_K/0/1/0/all/0/1">K. Hurley</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Iaria_R/0/1/0/all/0/1">R. Iaria</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kataria_D/0/1/0/all/0/1">D. Kataria</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Labanti_C/0/1/0/all/0/1">C. Labanti</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lodato_G/0/1/0/all/0/1">G. Lodato</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Negri_B/0/1/0/all/0/1">B.Read More →
Non-Newtonian gravity in strange quark stars and constraints from the observations of PSR J0740+6620 and GW170817. (arXiv:1909.00933v2 [astro-ph.HE] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Yang_S/0/1/0/all/0/1">Shu-Hua Yang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+PI_C/0/1/0/all/0/1">Chun-Mei PI</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Zheng_X/0/1/0/all/0/1">Xiao-Ping Zheng</a> We investigate the effects of non-Newtonian gravity on the properties of strange quark stars (QSs) and constrain the parameters of the standard MIT bag model used to describe strange quark matter (SQM) by employing the mass of PSR J0740+6620 and the tidal deformability of GW170817. We find that, for the standard MIT bag model, these mass and tidal deformability observations would rule out the existence of QSs if non-Newtonian gravity effects are ignored. For a strange quarkRead More →
Bias of Damped Lyman-$alpha$ systems from their cross-correlation with CMB lensing. (arXiv:1712.02738v2 [astro-ph.CO] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Alonso_D/0/1/0/all/0/1">David Alonso</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Colosimo_J/0/1/0/all/0/1">Joseph Colosimo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Font_Ribera_A/0/1/0/all/0/1">Andreu Font-Ribera</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Slosar_A/0/1/0/all/0/1">Anže Slosar</a> We cross-correlate the positions of damped Lyman-$alpha$ systems (DLAs) and their parent quasar catalog with a convergence map derived from the Planck cosmic microwave background (CMB) temperature data. We make consistent measurements of the lensing signal of both samples in both Fourier and configuration space. By interpreting the excess signal present in the DLA catalog with respect to the parent quasar catalog as caused by the large scale structure traced by DLAs, we are able to infer the biasRead More →
