Protoplanetary Disk: Simulated Spiral Arm vs. Observational Data: [Right] — Observations taken by the European Southern Observatory's Very Large Telescope show a protoplanetary disk around the young star MWC 758. The disk has two spiral arms that extend over 10 billion miles from the star. [Left] — A computer model reproduces the two-spiral-arm structure; the "x" is the location of a putative planet. The planet, which cannot be seen directly, probably excites the two spiral arms. NASA Press release

Name: MWC 758
Type: Milky Way : Star : Evolutionary Stage : Young Stellar Object
Category: Stars
Distance: 650 light years
Release date: 30 October 2015, 09:54
Credit: NASA, ESA, ESO, M. Benisty et al. (University of Grenoble), R. Dong (Lawrence Berkeley National Laboratory), and Z. Zhu (Princeton University)

Faint compact galaxy in the early Universe: This is a NASA/ESA Hubble Space Telescope view of a very massive cluster of galaxies, MACS0416.1-2403, located roughly 4 billion light-years away and weighing as much as a million billion suns. The cluster’s immense gravitational field magnifies the image of galaxies far behind it, in a phenomenon called gravitational lensing. The inset is an image of an extremely faint and distant galaxy that existed only 400 million years after the Big Bang. Hubble captured it because the gravitational lens makes the galaxy appear 20 times brighter than normal. The object is comparable in size to the Large Magellanic Cloud (LMC), a diminutive satellite galaxy of our Milky Way. It is rapidly making stars at a rate ten times faster than the LMC. The object might be the growing core of what was to eventually evolve into a full-sized galaxy. The research team has nicknamed the object Tayna, which means “first-born” in Aimara, a language spoken in the Andes and Altiplano regions of South America. NASA Press release

Name: MACS J0416.1-2403
Type: Local Universe : Galaxy : Grouping : Cluster
Category: Galaxies
Distance: z=0.396 (redshift)
Release date: 3 December 2015, 11:41
Credit: NASA, ESA, L. Infante (Pontificia Universidad Católica de Chile)

Stars similar to Eta Carinae in nearby galaxies: Researchers found likely Eta twins in four galaxies by comparing the infrared and  optical brightness of each candidate source. Infrared images from NASA's Spitzer Space Telescope revealed the presence of warm dust surrounding the stars. Comparing this information with the brightness of each source at optical and near-infrared wavelengths as measured by instruments on the NASA/ESA Hubble Space Telescope, the team was able to identify candidate Eta Carinae-like objects. Top: 3.6-micron images  of candidate Eta twins from Spitzer's IRAC instrument. Bottom: 800-nanometer  images of the same sources from various Hubble instruments. NASA Press release

Type: Early Universe : Star
Category: Stars
Release date: 7 January 2016, 09:58
Credit: NASA, ESA, and R. Khan (GSFC and ORAU)

Galaxy cluster IDCS J1426: Astronomers have made the most detailed study yet of an extremely massive young galaxy cluster using three space telescopes. This multi-wavelength image shows this galaxy cluster, called IDCS J1426.5+3508 (IDCS 1426 for short), in X-rays from the NASA Chandra X-ray Observatory in blue, visible light from the NASA/ESA Hubble Space Telescope in green, and infrared light from the NASA Spitzer Space Telescope in red. This rare galaxy cluster, which is located 10 billion light-years from Earth, weighs almost 500 trillion suns. This object has important implications for understanding how these megastructures formed and evolved early in the Universe. Astronomers have observed IDCS 1426 when the Universe was less than a third of its current age. It is the most massive galaxy cluster detected at such an early age. First discovered by the Spitzer Space Telescope in 2012, IDCS 1426 was then observed using the Hubble Space Telescope and the Keck Observatory to determine its distance. Observations from the Combined Array for Millimeter Wave Astronomy indicated it was extremely massive. New data from the Chandra X-ray Observatory confirm the galaxy cluster mass and show that about 90 percent of the mass of the cluster is in the form of dark matter, the mysterious substance that has so far been detected only through its gravitational pull on normal matter composed of atoms. There is a region of bright X-ray emission (seen as blue-white) near the middle of the cluster, but not exactly at the centre. The location of this "core" of gas suggests that the cluster has had a collision or interaction with another massive system of galaxies relatively recently, perhaps within about the last 500 million years. This would cause the core to "slosh" around like wine in a moving glass and become offset as it appears to be in the Chandra data. Such a merger would not be surprising, given that astronomers are observing IDCS 1426 when the universe was only 3.8 billion years old. So that an enormous structure can form so rapidly, scientists think mergers with smaller clusters would likely play a role in a large cluster's growth. This core, while still extremely hot, contains cooler gas than its surroundings. This is the most distant galaxy cluster where such a "cool core" of gas has been observed. Astronomers think these cool cores are important in understanding how quickly hot gas cools off in clusters, influencing the rate of stars at which stars are born. This cooling rate can be slowed down by outbursts from a supermassive black hole in the centre of the cluster. Apart from the cool core, the hot gas in the cluster is remarkably symmetrical and smooth. This is another piece of evidence that IDCS 1426 formed very rapidly and quickly in the early Universe. Despite the high mass and rapid evolution of this cluster, its existence does not pose a threat to the standard model of cosmology. These results were presented at the 227th meeting of the American Astronomical Society meeting in Kissimmee, Florida. NASA Press release

Name: IDCS J1426.5+3508
Type: Early Universe : Galaxy : Grouping : Cluster
Category: Galaxies
Constellation: Bootes
Release date: 8 January 2016, 12:41
Credit: NASA, ESA, and M. Brodwin (University of Missouri)