helium tagged posts

Artist’s concept of NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft in orbit above the moon. Credit: NASA Ames / Dana Berry

The presence of neon in the exosphere of the moon has been a subject of speculation since the Apollo missions, but no credible detections were made till now. There’s not enough neon to make the moon visibly glow because the moon’s atmosphere is extremely tenuous, about 100 trillion times less dense than Earth’s atmosphere at sea level. A dense atmosphere like Earth’s is relatively rare in our solar system because an object has to be sufficiently massive to have enough gravity to hold onto it.

The behavior of a dense atmosphere is driven by collisions between its atoms and molecules...

IMAGE: Artist’s impression of Gaia14aae.
Credit: Marisa Grove/Institute of Astronomy

It is a type of 2-star system known as a Cataclysmic Variable, where one super dense white dwarf star is stealing gas from its companion star, effectively ‘cannibalising’ it.The system could also be an important laboratory for studying ultra-bright supernova explosions, which are a vital tool for measuring the expansion of the Universe. The system, named Gaia14aae, is 730 light years away in Draco constellation. It was discovered by the ESA’s Gaia satellite in August 2014 when it suddenly became 5 times brighter over the course of a single day.

>>Additional observations made by the Center for Backyard Astrophysics (CBA), a collaboration of amateur and professional astronomers, found the system is a rare e...