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The beautiful mess in Abell 2255 An international team of astrophysicists led by Andrea Botteon from Leiden University, the Netherlands, has shed light on one of the most intricate objects of the radio sky: the galaxy cluster Abell 2255. Thanks to the incredible detailed images obtained with the European radio telescope LOFAR, the scientists have been able to observe details never seen before of the emission from the cluster. The halo in Abell 2255 is not smooth, but contains numerous filaments that have not been seen previously. The result has been presented today at the virtual annual meeting of the European Astronomical Society (EAS) andRead More →

Giant star spots likely cause of Betelgeuse dimming Betelgeuse, the bright star in the constellation of Orion, has been fascinating astronomers in the recent months because of its unusually strong decline in brightness. Scientists have been discussing a number of scenarios trying to explain its behavior. Now a team led by Thavisha Dharmawardena of the Max Planck Institute for Astronomy have shown that most likely unusually large star spots on the surface of Betelgeuse have caused the dimming. Their results rule out the previous conjecture that it was dust, recently ejected by Betelgeuse, which obscured the star. phys.org Go to SourceRead More →

Astronomers investigate chemical composition of a nearby star-forming dwarf galaxy Using ESO’s Very Large Telescope (VLT), astronomers have probed the chemical composition of a nearby metal-poor star-forming dwarf galaxy known as JKB 18. Results of the new observations indicate that the galaxy is chemically inhomogeneous. The study was published June 18 on the arXiv pre-print server. phys.org Go to SourceRead More →

Image: Hubble captures galaxy on edge The galaxy known as NGC 5907 stretches wide across this image. Appearing as an elongated line of stars and dark dust, the galaxy is categorized as a spiral galaxy just like our own Milky Way. In this new image from the NASA/ESA Hubble Space Telescope, we don’t see the beautiful spiral arms because we are viewing it edge-on, like looking at the rim of a plate. It is for this reason that NGC 5907 is also known as the Knife Edge galaxy. phys.org Go to SourceRead More →

First measurement of spin-orbit alignment on planet Beta Pictoris b Astronomers have made the first measurement of spin-orbit alignment for a distant ‘super-Jupiter’ planet, demonstrating a technique that could enable breakthroughs in the quest to understand how exoplanetary systems form and evolved. phys.org Go to SourceRead More →

Inferring the temperature structure of circumstellar disks from polarized emission Polarized light is a familiar phenomenon because the scattering or reflection of light results in one of its two components being preferentially absorbed. The majority of sunlight on Earth, for example, is preferentially polarized due to scattering in the atmosphere (this helps make polarized sunglasses effective). Electromagnetic radiation from astrophysical sources can also be polarized, typically because of scattering from elongated dust grains that are aligned with each other by the local magnetic fields. These fields are thought to play a major, perhaps even a dominant role in controlling the shapes and motions of interstellarRead More →

Super-Earths discovered orbiting nearby red dwarf The nearest exoplanets to us provide the best opportunities for detailed study, including searching for evidence of life outside the solar system. In research led by the University of Göttingen, the RedDots team of astronomers has detected a system of super-Earth planets orbiting the nearby star Gliese 887, the brightest red dwarf star in the sky. Super-Earths are planets which have a mass higher than the Earth’s but substantially below those of our local ice giants, Uranus and Neptune. The newly discovered super-Earths lie close to the red dwarf’s habitable zone, where water can exist in liquid form, andRead More →

Motions in the sun reveal inner workings of sunspot cycle The sun’s magnetic activity follows an 11-year cycle. Over the course of a solar cycle, the sun’s magnetic activity comes and goes. During solar maximum, large sunspots and active regions appear on the sun’s surface. Spectacular loops of hot plasma stretch throughout the sun’s atmosphere and eruptions of particles and radiation shoot into interplanetary space. During solar minimum, the sun calms down considerably. A striking regularity appears in the so-called butterfly diagram, which describes the position of sunspots in a time-latitude plot. At the beginning of a solar cycle, sunspots emerge at mid-latitudes. As theRead More →

Astronomers discover ‘monster’ quasar from early universe Astronomers have discovered the most massive quasar known in the early universe, containing a monster black hole with a mass equivalent to 1.5 billion suns. Formally designated as J1007+2115, the newly discovered quasar is one of only two known from the same cosmological period. Quasars are the most energetic objects in the universe, and since their discovery, astronomers have been keen to determine when they first appeared in our cosmic history. phys.org Go to SourceRead More →

Drones help calibrate radio telescope at Brookhaven Lab Cosmologists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory are experimenting with a prototype radio telescope, called the Baryon Mapping Experiment (BMX). Built at the Lab in 2017, the prototype serves as a testbed for managing radio interference and developing calibration techniques. Lessons learned from the prototype could pave the way for Brookhaven to develop a much larger radio telescope in collaboration with other national Labs, universities, and international partners. Such a telescope would map neutral hydrogen over large swaths of the universe, enabling researchers to gain a better understanding of its accelerated expansion, asRead More →

Hubble sees a cosmic flapping ‘Bat Shadow’ Sometimes nicknames turn out to be closer to reality than you might imagine. phys.org Go to SourceRead More →

First detector array ready for GUSTO mission The first detector array for NASA’s GUSTO mission has passed its pre-shipment review and is now shipping to the University of Arizona for integration into the balloon observatory. SRON together with TU Delft develops GUSTO’s three 8-pixel-arrays, for the frequencies 4.7, 1.9 and 1.4 terahertz. They have now finished the array for the 4.7 terahertz channel—the most challenging part. GUSTO is a balloon mission that will measure emissions from cosmic material between stars. phys.org Go to SourceRead More →