Recommended Alien Intrusion by Gary Bates

Astronomers Had it Wrong: Most Stars are Single

For more than 200 years, astronomers thought that most of the stars in our galaxy had stellar companions. But a new study suggests the bulk of them are born alone and never have stellar company.

Since planets are believed to be easier to form around single stars, the discovery could mean planets are more common as well.

Conventional wisdom on double star systems, called binaries, goes as far back as the late 1700s. More sophisticated observations made in the 20th century seemed to confirm the numerical dominance of pairs.

Stellar surveys found that more than half of all Sun-like stars were part of multiple systems. For more massive stars, like O- and B-type stars, the number was estimated to be as high as 80 percent.

[. . .]

Although some studies suggest that planet formation around binary star systems is more common than previously thought, most astronomers believe that making planets is still easier around single stars. It’s thought that when there are two or more stars, the gravitational forces between them hinder matter from clumping into cores dense enough to form planets.

If single stars are the rule and not the exception, as the new finding suggests, then extrasolar planets may be more common as well.

After 3 Billion Miles, Craft Returns Sunday Bearing Cosmic Dust Older Than the Sun

In a blaze across the night sky, it should be a spectacular homecoming at the end of a very, very long journey.

After covering 2.88 billion miles over seven years, the Stardust spacecraft is nearing home with its minute but precious cargo: samples of what are believed to be the oldest materials in the solar system.

Tucked away in what looks like a giant fly swatter of a collector is dust swooped up from a close encounter with the comet Wild 2 and an accumulation of particles picked up in three circuits of the Sun.

“This has been a fantastic opportunity to collect the most primitive material in the solar system,” said Donald Brownlee of the University of Washington, the principal investigator for the mission. “We fully expect some of the comet particles to be older than the Sun.”

Comets, icy bodies that normally inhabit a region near Pluto's orbit, are made of material many scientists believe is virtually unchanged since the Sun and the planets formed about 4.6 billion years ago.

Studying comets not only provides clues to how the solar system was created but could also help explain how certain materials and conditions combined to form life, researchers said.