The three iconic space pillars photographed by NASA’s Hubble Space Telescope in 1995 might have met their demise, according to new evidence from NASA’s Spitzer Space Telescope. The striking image from Spitzer shows the intact dust towers next to a giant cloud of hot dust thought to have been scorched by the blast of a star that exploded. Astronomers speculate that the supernova’s shock wave could have already reached the dusty towers, causing them to topple about 6.000 years ago. However, because light from this region takes 7.000 years to reach Earth, we won’t be able to capture photos of the destruction for another 1.000 years or so.

https://www.spitzer.caltech.edu/news/ssc2007-01-famous-space-pillars-feel-the-heat-of-stars-explosion

Researchers from the Sloan Digital Sky Survey (SDSS-II) announced the discovery of eight new dwarf galaxies, seven of them satellites orbiting the Milky Way. The objects resemble systems cannibalized by the Milky Way billions of years ago to build up its stellar halo and thick disk, characterized as „crumbs from the galactic feast“. The systems discovered by the SDSS-II in the last three years are comparable in number to all the Milky Way satellites detected in the preceding 70 years. They help close the gap between the observed number of dwarf satellites and theoretical predictions.

http://classic.sdss.org/news/releases/20070109.dwarfs.html

Astronomers generally assume that the dusty disks where planets form are found around young stars in stellar nurseries. Now, for the first time, a planet-forming disk has been found in the environment of a dying star. A team of astronomers is reporting at the meeting of the American Astronomical Society that material from the dying star Mira A is being captured into a disk around Mira B, its companion. Michael Ireland of the California Institute of Technology and his coauthors say that the finding implies that there should be many similar undiscovered systems in the solar neighborhood, providing a myriad of new places to look for young planets orbiting stars other than our Sun. Located 350 light years away in the constellation of Cetus, Mira first shook the foundations of the astronomy world 400 years ago with its changing brightness: visible to the naked eye for about 1 month at a time, becoming 1.000 times fainter and disappearing from view, only to re-appear again on an 11 month cycle. Although Mira was once a star very similar to the sun, it is now in its death throes as it loses its dusty outer layers at a rate of one Earth-mass every seven years. If Mira were a single star, all this material would travel into outer space. However, like two out of every three star systems, Mira has a companion star that orbits around it, in this case with a period of about 1.000 years. This companion, Mira B, has a gravitational field that catches nearly one percent of the material lost from Mira A. By using specialized high-contrast techniques at the 10-meter Keck I telescope in Hawaii and the 8-meter Gemini South telescope in Chile, Michael Ireland’s team discovered heat radiation coming not from Mira B itself, but also from a location offset from Mira B by a distance equivalent to Saturn’s orbit.
First Planet-Forming Disk Found in the Environment of a Dying Star

The distribution of dark matter has been mapped in 3D for the first time, revealing how the mysterious substance has evolved over the lifetime of the universe. The results confirm that dark matter provided the scaffolding that allowed ordinary matter to clump together to form galaxies and clusters of galaxies. Dark matter is an invisible substance that betrays its presence through the gravitational tug it exerts on ordinary matter. It is six times more abundant than ordinary matter and is thought to have seeded the first distinct structures in the universe, which began as a very uniform soup of matter. Computer simulations suggest that the formation of dark matter clumps attracted surrounding gas, which then condensed to form galaxies and galaxy clusters. But this dark matter clumping process had never been confirmed observationally. Now, astronomers have mapped the changing distribution of both dark matter and ordinary matter over time. Nick Scoville, of Caltech in Pasadena, US, led the Cosmic Evolution Survey (COSMOS), which combined data from the world’s leading observatories to produce the map. The key to determining the dark matter distribution is an effect called gravitational lensing, by which light rays from a distant object such as a galaxy are bent by the gravity of an intervening concentration of matter. Although dark matter cannot be seen directly, its presence can be inferred by the way its gravity distorts the images of galaxies behind it. The Hubble Space Telescope (HST) mapped out these distortions over a patch of sky equivalent to the width of four Full Moons in the largest survey it has ever performed. It devoted 10% of its time over two years to complete the survey. The Subaru telescope on Mauna Kea, Hawaii, and the Very Large Telescope in Paranal, Chile, measured the spectrum of light from galaxies seen by Hubble, which allowed the galaxies‘ distances to be calculated. The XMM-Newton X-ray satellite contributed by mapping gas within galaxies and galaxy clusters – the most abundant form of ordinary matter in those objects.
These results were presented on Sunday at a meeting of the American Astronomical Society in Seattle, Washington, US.
COSMOS

Hubble Maps the Cosmic Web of „Clumpy“ Dark Matter in 3-D

First 3D map of the Universe’s dark matter scaffolding

The discovery of several large, metal-poor stars located far from the center of the Andromeda galaxy suggests our nearest galactic neighbour might be up to five times larger than previously thought. The newfound stars are massive, bloated stars known as red giants. Although found far beyond the most visible portion of Andromeda’s swirling disk, the stars are still gravitationally bound to the galaxy and make up part of its extended „halo“. The finding, presented on Sunday at the 209th meeting of the American Astronomical Society, suggests Andromeda is at least one million light-years across and could help settle a discrepancy between Andromeda and the Milky Way that has long puzzled astronomers.
Astronomers discover an enormous halo of red giant stars around Andromeda