Category Astronomy/Space

The star VY Canis Majoris is a red hypergiant, one of the largest known stars in the Milky Way. It is 30-40 times the mass of the Sun and 300 000 times more luminous. In its current state, the star would encompass the orbit of Jupiter, having expanded tremendously as it enters the final stages of its life. New observations of the star using the SPHERE instrument on the VLT have clearly revealed how the brilliant light of VY Canis Majoris lights up the clouds of material surrounding it and have allowed the properties of the component dust grains to be determined better than ever before. In this very close-up view from SPHERE the star itself is hidden behind an obscuring disc. The crosses are artefacts due to features in the instrument. Credit: ESO

Giant star caught in the act of slimming do...

Mars could gain a ring in 10-20 million years when its moon Phobos is torn to shreds by tidal forces due to Mars’ gravitational pull. Credit: Image by Tushar Mittal using Celestia 2001-2010, Celestia Development Team.

In 10-20 million years, the moon will get so close to Mars that it’ll be shredded into a ring, eventually be torn apart by tidal forces and distributed in a ring around the planet, a study of the cohesiveness of Phobos has concluded. This would take about 10-20 million years, and the ring will persist for up to 100 million years before the dust falls into Mars’ atmosphere and burns up as ‘moon’ showers.

The loss is due to Phobos being highly fractured, with lots of pores and rubble...

Image of the inner 3 square degrees of the NGFS survey footprint compared with the size of the Moon. Low surface brightness dwarf galaxies are marked by red circles. Gray circles indicate previously known dwarf galaxies. The dwarf galaxies, which vastly outnumber the bright galaxies, may be the “missing satellites” predicted by cosmological simulations.

The discovery was carried out using the Dark Energy Camera (DECam) on the 4-m Blanco telescope at Cerro Tololo Inter-American Observatory (CTIO). Computer simulations of the evolution of the matter distribution in the Universe predict that dwarf galaxies should vastly outnumber galaxies like the Milky Way, with hundreds of low mass dwarf galaxies predicted for every Milky Way-like galaxy...

Space telescope Herschel (2009-2013) allowed fascinating insight into the birth of stars. Credit: ESA

The results are important for space missions that have already been planned, such as the James Webb Space Telescope (JWST), for which temps of use < -220 °C are planned, or Space Infrared Telescope for Cosmology and Astrophysics (SPICA), for which even lower temps are envisaged.

Space holds numerous fascinating objects which we can only investigate by observing their radiation. For space telescopes such as ESA infrared observatory Herschel, whose mission is to observe radiation in the far-infrared, cooling the instruments is of importance, since the instruments themselves must not emit disturbing infrared radiation...