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Queenstown, New Zealand October 14, 2015 Image Credit & Copyright: Minoru Yoneto

The NASA/ESA Hubble Space Telescope has been on the forefront of research into the lives of stars like our Sun. At the ends of their lives, these stars run out of nuclear fuel in a phase that is called the preplanetary or protoplanetary nebula stage. This Hubble image of the Egg Nebula shows one of the best views to date of this brief, but dramatic, phase in a star's life. During the preplanetary nebula phase, the hot remains of an aging star in the center of the nebula heat it up, excite the gas and make it glow over several thousand years. The short lifespan of preplanetary nebulae means there are relatively few of them in existence at any one time. Moreover, they are very dim, requiring powerful telescopes to be seen. This combination of rarity and faintness means they were only discovered comparatively recently. The Egg Nebula, the first to be discovered, was first spotted less than 40 years ago, and many aspects of this class of object remain shrouded in mystery. At the center...

A giant impact between the proto-Earth and a Mars-sized impactor named Theia is the best current theory for the formation of the Moon. Scientists believe that Theia collided with the early Earth and that the Moon was created from the rubble left over from the collision. Researchers have estimated that more than 40% of the Moon-forming debris should have been derived from left over pieces of Theia, but new research by a team of geochemists led by Junjun Zhang at the University of Chicago suggests that the Moon is made mostly of material from early Earth instead. The team analyzed Oxygen isotopes and found that terrestrial and lunar samples were almost identical, which is inconsistent with earlier models. The researchers measured ratios in lunar samples measured by mass spectrometry. After correcting for secondary effects associated with cosmic-ray exposure at the lunar surface, they found that the ratio of the Moon is identical to that of the Earth within about four parts per million, w...

The NASA/ESA Hubble Space Telescope has once more turned its attention towards the magnificent Eagle Nebula (Messier 16). This picture shows the northwestern part of the region, well away from the centre, and features some very bright young stars that formed from the same cloud of material. These energetic toddlers are part of an open cluster and emit ultraviolet radiation that causes the surrounding nebula to glow. The star cluster is very bright and was discovered in the mid-eighteenth century. The nebula, however, is much more elusive and it took almost a further two decades for it to be first noted by Charles Messier in 1764. Although it is commonly known as the Eagle Nebula, its official designation is Messier 16 and the cluster is also named NGC 6611. One spectacular area of the nebula (outside the field of view) has been nicknamed “The Pillars of Creation” ever since the Hubble Space Telescope captured an iconic image of dramatic pillars of star-forming gas and dust. The cluster...

Ifjord, Finnmark, Norway September 26, 2011 Image Credit & Copyright: Tommy Eliassen

A primitive ocean on Mars held more water than Earth’s Arctic Ocean, according to NASA scientists who, using ground-based observatories, measured water signatures in the Red Planet’s atmosphere. Scientists have been searching for answers to why this vast water supply left the surface. “Our study provides a solid estimate of how much water Mars once had, by determining how much water was lost to space,” said Geronimo Villanueva, a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “With this work, we can better understand the history of water on Mars.” Perhaps about 4.3 billion years ago, Mars would have had enough water to cover its entire surface in a liquid layer about 450 feet (137 meters) deep. More likely, the water would have formed an ocean occupying almost half of Mars’ northern hemisphere, in some regions reaching depths greater than a mile (1.6 kilometers). The new estimate is based on detailed observations made at the European Southern Observatory’s Ver...

The barred spiral galaxy NGC 6217 was photographed on 13 June and 8 July 2009, as part of the initial testing and calibration of Hubble’s ACS. The galaxy lies up to 90 million light-years away in the north circumpolar constellation Ursa Major. Image Credit: NASA, ESA and the Hubble SM4 ERO Team