Mars is now known as the planet who lost an ocean’s worth of water. According to new results published today, about 4 billion years ago a primitive ocean on Mars held more water than Earth’s Arctic Ocean. Above’s an artist’s impression showing how Mars may have looked.

An international team of scientists used European Southern Observatoy’s Very Large Telescope, along with instruments at the W. M. Keck Observatory and the NASA Infrared Telescope Facility, to monitor the atmosphere of the planet and map out the properties of the water in different parts of Mars’s atmosphere over a six-year period. read more here
illustration credit: ESO/M. Kornmesser/N. Risinger (skysurvey.org)

All four stages of the rocket are visible in this time lapse photo of the NASA Oriole IV sounding rocket with Aural Spatial Structures Probe, launched from Poker Flats, Alaska

Fastest Star Ever Seen Will Escape from the Galaxy

The compact star US 708 hasn’t had an easy life. Paired with a domineering partner, 708’s mass was siphoned away, reducing it to a dense, helium-filled core.

But 708 didn’t go quietly into the night. Instead, scientists believe the feeding frenzy ended in a supernova explosion that catapulted the ravaged remains with such force it’s leaving the galaxy. Fast.

A new study shows that the star, classified as a hot subdwarf, is blasting through the Milky Way at about 750 miles per second, faster than any other star in the galaxy. Read more

Thor’s Helmet

This stunning image shows the nebula cataloged as NGC 2359, but more commonly known as Thor’s Helmet. It does bear a striking resemblance to the headpiece worn by the Norse god, right down to the wings. The nebula, roughly 30 light-years across, is located about 15,000 light-years away in the constellation Canis Major.

Powering up this nebula is a Wolf-Rayet (WR) star known as HD 56925. WR stars are hot, massive giants late in their evolutionary cycles. This O-type giant, perhaps 20 times more massive than the Sun, has gone through a rapid loss of mass, casting most of its hydrogen out into space. The powerful stellar winds carrying this material outward shock the surrounding interstellar medium, causing it to glow. The wing structures were likely thrown off earlier by the progenitor star, while the central helmet portion of the nebula is a more recent bubble blown by the O-type blue giant.

The Thor’s Helmet nebula is not immortal. The central Wolf-Rayet star, having jettisoned most of its hydrogen outward, begins to fuse heavier elements, but that fusion process will end at iron. The outward pressure from fusion will cease, and the inward pressure of gravity will crush the star down, creating a supernova explosion. The nebula won’t survive the blast, but perhaps the resulting supernova remnant will take on an interesting shape of its own.

For a larger version of this image, go here:http://bit.ly/1KOMSEu


Image credit & copyright: Adam Block/Mount Lemmon SkyCenter/University of Arizona

Sources: 1, 2, 3