NASA's Hubble Finds Stellar Life and Death in a Globular Cluster

A new NASA Hubble Space Telescope image shows globular cluster NGC 1846, a spherical collection of hundreds of thousands of stars in the outer halo of the Large Magellanic Cloud, a neighboring dwarf galaxy of the Milky Way that can be seen from the southern hemisphere.

Aging bright stars in the cluster glow in intense shades of red and blue. The majority of middle-aged stars, several billions of years old, are whitish in color. A myriad of far distant background galaxies of varying shapes and structure are scattered around the image.

The most intriguing object, however, doesn’t seem to belong in the cluster. It is a faint green bubble near the bottom center of the image. This so-called ‘planetary nebula’ is the aftermath of the death of a star. The burned-out central star can be seen inside the bubble. It is uncertain whether the planetary nebula is a member of NGC 1846, or simply lies along the line of sight to the cluster. Measurements of the motion of the cluster stars and the planetary nebula’s central star suggest it might be a cluster member.

This Hubble image was taken with the Advanced Camera for Surveys in January of 2006. The cluster was observed in filters that isolate blue, green, and infrared starlight. As a member of the Large Magellanic Cloud, NGC 1846 is located roughly 160,000 light-years away in the direction of the constellation Doradus.

Diamond stud

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Star Blasts Planet With X-rays

A nearby star is pummeling a companion planet with a barrage of X-rays 100,000 times more intense than the Earth receives from the sun.

New data from NASA's Chandra X-ray Observatory and the European Southern Observatory's Very Large Telescope suggest that high-energy radiation is evaporating about 5 million tons of matter from the planet every second. This result gives insight into the difficult survival path for some planets.

The planet, known as CoRoT-2b, has a mass about three times that of Jupiter -- 1,000 times that of Earth -- and orbits its parent star, CoRoT-2a at a distance roughly 10 times the distance between Earth and the moon.

The CoRoT-2 star and planet -- so named because the French Space Agency’s Convection, Rotation and planetary Transits, or CoRoT, satellite discovered them in 2008 -- is a relatively nearby neighbor of the solar system at a distance of 880 light years.

"This planet is being absolutely fried by its star," said Sebastian Schroeter of the University of Hamburg in Germany. "What may be even stranger is that this planet may be affecting the behavior of the star that is blasting it."

According to optical and X-ray data, the CoRoT-2 system is estimated to be between about 100 million and 300 million years old, meaning that the star is fully formed. The Chandra observations show that CoRoT-2a is a very active star, with bright X-ray emission produced by powerful, turbulent magnetic fields. Such strong activity is usually found in much younger stars.

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MAVEN Mission to Investigate How Sun Steals Martian Atmosphere

The Red Planet bleeds. Not blood, but its atmosphere, slowly trickling away to space. The culprit is our sun, which is using its own breath, the solar wind, and its radiation to rob Mars of its air. The crime may have condemned the planet's surface, once apparently promising for life, to a cold and sterile existence.

Features on Mars resembling dry riverbeds, and the discovery of minerals that form in the presence of water, indicate that Mars once had a thicker atmosphere and was warm enough for liquid water to flow on the surface. However, somehow that thick atmosphere got lost in space. It appears Mars has been cold and dry for billions of years, with an atmosphere so thin, any liquid water on the surface quickly boils away while the sun's ultraviolet radiation scours the ground.

Enormous Star blazes speedy and enraged in snap

An exceptional model of enormous stars that survive fast and die young has been photographed by a European observatory in Chile.The blazing hot star is called WR 22 and is detaching its atmosphere many millions of times sooner than our own sun in external blasts that unleash powerful radiation releases.

t has about 70 times the mass of the sun, and its brightness permits Earth spectators to spot its intensity with the unaided eye from over 5,000 light-years away. A light-year is about 6 trillion miles, the distance light travels in a year.

WR 22 sits in a southern arrangement of stars, the Carina Constellation, which symbolizes the keel of Jason's ship Argo in Greek mythology. It is one of many incredibly bright stars in the Carina Nebula a giant province of star structure in the southern Milky Way galaxy.

The astronomical sighting came from European Southern Observatory's La Silla Observatory. Its colorful image imitates the interactions between the extreme ultraviolet radiation coming from hot massive stars such as WR 22 and vast gas clouds composed mostly of hydrogen.

The upper-left image also contains the star Eta Carinae, just 7,500 light-years away and more than 100 times the mass of our sun. Astronomers expect such gigantic stars to lose their entire hydrogen envelopes before they go out with a supernova bang.