Most Extreme Space Discoveries of 2012
Life is very unlikely on this world. Its rocky surface may be molten, since the planet orbits just 3.6 million miles (6 million kilometers) from its sun-like star. (Earth, for comparison, circles 93 million miles, or 150 million km, from the sun).
Alpha Centauri Bb, as the planet is known, was discovered through tracking gravitational wobbles around its planet star. The wobbles in this case are very subtle, making the star move back and forth at no more than 1.1 mph (1.8 kph). The research team stated it “pushed our technique to the limit,” and some astronomers are skeptical that the planet even exists.
And just this month, a different research team detected five potential planets orbiting the star Tau Ceti, which lies only 11.9 light-years from Earth. One of the newly spotted candidate worlds may be capable of supporting life as we know it, scientists say.
Smallest alien worlds
“This is the most compact system of planets,” said John Johnson, of the California Institute of Technology in Pasadena. “It’s like you have a shrink raygun and set it to seven times smaller and zapped a planetary system.”
Smallest solar system
KOI-500 has five planets so crowded together that their gravity jostles each other profoundly during their orbits. Their “years” are only 1, 3, 4.6, 7.1 and 9.5 days long. Furthermore, the planets are tiny: just 1.3 to 2.6 times the size of Earth.
All of this action takes place in an area 150 times smaller than Earth’s orbit, astronomers said.
“At this rate, you could easily pack in 10 more planets, and they would still all fit comfortably inside the Earth’s orbit,” Darin Ragozzine, a planetary scientist at the University of Florida at Gainesville, said in a statement.
Most distant galaxy
The galaxy is part of a group of seven that astronomers examined, forming perhaps the first reliable observations of galaxies that formed 400 million and 600 million years after the Big Bang created the universe 13.7 billion years ago.
Oldest, most distant supernovas
In 2012, astronomers described what they think led to the oldest, most distant supernovas in the universe. Scientists believe some of these “super-luminous” supernovas come from massive stars — 100 to 250 times the mass of the sun — that explode and blast their matter into space.
Astronomers stated that inside these massive stars, gamma-ray light changes into electron pairs as well as antimatter positrons. The gamma rays usually stop the star from collapsing due to gravity, but the grip weakens as gamma rays convert to matter. It is at this point that the star implodes, sparking the explosion.
Most massive galaxy cluster
At 2,000 times more massive than the Milky Way, a large cluster of galaxies some 7 billion light-years away dwarfs just about any other collection of matter known. Astronomers say the cluster — properly known as SPT-CLJ2344-4243and dubbed the Phoenix cluster — appears to contain thousands of galaxies of many different sizes.
Hubble’s picture, which is called the eXtreme Deep Field, shows galaxies and starlight accumulated over 10 years in a small bit of sky; this is the best method we have to see objects so far away. The photo is a successor to Hubble’s “Ultra Deep Field”, which the telescope took in 2003 and 2004.
Most magnetic star
There’s a star 20,000 light-years from Earth with a real magnetic personality. NGC 1624-2, which is about 35 times as massive as our sun, was spotted in the constellation Perseus. With a magnetic field 20,000 times stronger than the sun’s— and 10 times more powerful than that of any known star — NGC 1624-2 drags a blanket of trapped charged particles around it.
“Magnetic fields of this strength are extremely rare; they are only known to exist in a few other stars of much lower mass,” study lead author Gregg Wade, an astronomer at the Royal Military College of Canada, told SPACE.com in a September interview. “To find such a strong field is very lucky.”
X-ray blast in the universe’s youth
A jet of X-rays emanating from quasar GB 1428 — a galaxy that has a huge black hole in its center — was found about 12.4 billion light-years from Earth. The radiation band is estimated at about twice the diameter of the Milky Way.