Category Astronomy/Space

ALMA image of HL Tau at left; VLA image, showing clump of dust, at right. Credit: Carrasco-Gonzalez, et al.; Bill Saxton, NRAO/AUI/NSF

New images of a young star made with Very Large Array (VLA) reveal what scientists think may be the very earliest stages in the formation of planets, 450 light-years from Earth. A previous 2014 ALMA image showed gaps in the disk, presumably caused by planet-like bodies sweeping out the dust along their orbits. This image, showing in real life what theorists had proposed for years, was surprising, however, because the star, called HL Tau, is only about a million years old – very young by stellar standards.

The ALMA image showed details of the system in the outer portions of the disk, but in the inner portions of the disk, nearest to the young star, the thick...

The centre of our galaxy is home to many objects capable of producing cosmic rays of high energy, including, in particular, a supernova remnant, a pulsar wind nebula, and a compact cluster of massive stars. Credit: Image courtesy of CEA

For >10 yrs H.E.S.S. observatory, Namibia, run by a collaboration of 42 institutions in 12 countries, has been mapping the centre of our galaxy in very-high-energy gamma rays produced by cosmic rays from the innermost region of the Galaxy. A detailed analysis of the latest H.E.S.S...

The Milky Way in the 2MASS infrared survey, similar to Hubble observations of the sky colour (near-infrared). Here, the visible stars are mostly bright giant stars. Credit: The Infrared Processing and Analysis Center (IPAC) http://www.ipac.caltech.edu/2mass/gallery/2mass_allskyatlas.jpg

The Leiden Uni students show there are 58 billion dwarf stars, of which 7% reside in the outer regions of our Galaxy. This result is the most comprehensive model ever for the distribution of these stars. The Milky Way has a prominent, relatively flat disc with closely spaced bright stars, and a halo, a sphere of stars with a much lower density around it. Astronomers assume that the halo is the remnant of the first galaxies that fused together to form our Galaxy.

To find out exactly what the Milky Way looks ...

In this artist’s illustration, the young Sun-like star Kappa Ceti is blotched with large starspots, a sign of its high level of magnetic activity. New research shows that its stellar wind is 50 times stronger than our Sun’s. As a result, any Earth-like planet would need a magnetic field in order to protect its atmosphere and be habitable. The physical sizes of the star and planet and distance between them are not to scale. Credit: M. Weiss/CfA

Nearly 4B years ago, life arose on Earth. Life appeared because our planet had a rocky surface, liquid water, and a blanketing atmosphere. But life thrived thanks to another necessary ingredient: the presence of a protective magnetic field...