AstroUnit

For the first time, a giant exoplanet has been discovered orbiting a dead star (which in this case happens to a white dwarf) every 1.4 days. The planet is roughly the same size as Jupiter and is no more than 14 times as massive and has an equilibrium temperature of 165 K. The mass of the white dwarf is approximately 0.5 solar masses and with the radius roughly 10% that of the Sun. The groundbreaking discovery demonstrated that giant planets can be scattered into tight orbits without being tidally disrupted, and motivates searches for smaller transiting planets around white dwarfs. NGC 2392: A planetary nebula, a phase that results when a star like the Sun becomes a red giant and sheds its outer layers. Source:  Chandra Exoplanet research is clearly amongst the most interesting research topics in astronomy. With the advancement of high-quality telescopes and detectors, thousands of exoplanets have been discovered and the numbers are only projected to surge in the coming years. Norma...

A large team of astronomers discovered the first asteroid inside the orbit of Venus using the Zwicky Transient Facility  located at the Palomar Observatory in California, United States. The asteroid has been named 2020 AV2 and is roughly 2 km in size with an aphelion distance (i.e., the point in the orbit of an object where it is farthest from the Sun ) of 0.65 astronomical units. The discovery could very well indicate that there may be a yet undiscovered population of asteroid lying outside of the asteroid belt and if more such asteroids are discovered,  currently favored asteroid population models may need to be adjusted. Image of the largest asteroid Ceres. Source  Wikipedia As of this writing, almost all of  1 million known asteroids  lie between the orbits of Mars and Jupiter with only a handful lying near the orbit of Earth.  Many scientists argue that there must be another population of asteroids present near the orbit of Venus. However, no such ast...

A team of astronomers made a groundbreaking discovery of six closely bound galaxies being powered by a single supermassive black hole with a mass greater than a billion solar masses at a redshift of 6.31. Out of the six galaxies, four are massive star-forming galaxies and the other two are comparatively low mass galaxies. This is the first discovery of a galactic overdensity around a supermassive black hole in the first billion years of the Universe and confirms the idea that the most distant and massive black holes form and grow within massive dark matter halos in large scale structures.   MS 0735.6+7421: Six objects ranging in location from within the Milky Way to billions of light-years away: Source:  Chandra One of the major challenges in astronomy is to explain the existence of supermassive black holes powering luminous quasars at high redshifts. A quasar is an extremely bright active galactic nucleus fueled by a supermassive black hole. Quasars are typical of the size of...

A team of astronomers has discovered a new exoplanet named TOI-824 b orbiting a nearby star TOI-824 which is only 208 light-years away from us. The planet is massive in size with a mass equivalent to almost 19 times that of the Earth and has a radius equal to 3 times that of the Earth. The planet has an orbital period of 1.393 days and has a mean density of roughly 4 gm/cc making it more than twice as dense as Neptune. The discovery was made using data from the Transiting Exoplanet Survey Satellite (TESS).                        An artist’s impression of an exoplanet. Source:  Alpha Coders As the name suggests, an exoplanet is a planet outside the solar system. The first confirmed detection of an exoplanet was made in 1992 by astronomers Aleksander Wolszczan and Dale Frail. On 6 October 1995, Michel Mayor and Didier Queloz discovered the first exoplanet orbiting a Sun-like star. This discovery was groundbreaking and opened...

  A team of cosmologists compared the theoretical predictions of the maximal abundance of massive galaxies predicted in different dynamical dark energy (DDE) models at high redshifts z ≈ 4 − 7 with the observed abundance and derived constraints for the evolution of the dark energy equation of state parameter which is complementary to the existing probes. The study employed three different, independent probes, namely the luminous end of the stellar mass function at z ≥ 6, the spatial density of luminous galaxies detected in the submillimeter range at z = 4 − 5, and the rareness of the extreme hyperluminous infrared galaxy SPT031158 at z ≈ 7. The analysis excluded a significant fraction of parameter spaces for the DDE models but interestingly does not completely exclude the possibility that dark energy may be dynamical (i.e, changing with time). Deepest visible-light image of the Universe containing nearly 10000 galaxies. Source:  Hubble According to our current understanding of...

  A team of astronomers used deep radio observations from 53 MHz to 1.5 GHz with the LOFAR Low/High Band Antenna (LBA/HBA) arrays, the Jansky Very Large Array (JVLA) and the upgraded Giant Metrewave Radio Telescope (GMRT) and discovered the existence of a giant radio bridge connecting two pre-merging galaxy clusters A1758N and A1758S that are ~ 2 Mpc apart. This is the second large-scale radio bridge observed to date in a cluster pair. By studying the radio and X-ray emissions from the radio bridge, the astronomers found clear-cut evidence that the non-thermal phenomena in the intracluster medium (ICM) can be produced in the region of compressed gas in-between infalling systems.  Cluster Merger: Galaxy Clusters Caught in a First Kiss. Source:  Chandra The existence of radio bridges connecting pre-merging galaxy clusters has been confirmed very recently. Hitherto, only two such systems, namely A1758N-A1758S situated at a redshift of z ...