From the first Earth-size planets beyond our solar system to a "UFO" that turned out to be a U.S. military drone, this week had its share of intriguing stories. <br><br>See the stories that made our top list for the week and vote for your favorite here.
Billed as the nation’s first dedicated commercial spaceport, New Mexico's Spaceport America is becoming a desirable location to experiment with new types of reusable booster systems. <br><br>Armadillo Aerospace, of Heath, Texas, used the site on Dec. 4 to test their STIG A reusable suborbital rocket technology. The U.S. Air Force plans to use the site for tests of its own unmanned reusable rocket prototypes. [<a href=http://www.space.com/13970-spaceport-america-reusable-rockets-tests.html>Full Story</a> <br><br>NEXT: First Alien Earth-Size Planets Found
Two planets orbiting a star 950 light-years from Earth are the smallest, most Earth-size alien worlds known, astronomers announced today (Dec. 20). One of the planets is actually smaller than Earth, scientists say. The alien planet Kepler-20e is the smallest exoplanet known. An artist's rendering of the newfound alien planet Kepler-20e, which scientists say is smaller than Earth, at about 0.87 times the width of our planet. CREDIT: NASA/JPL-Caltech/T. Pyle View full size image These planets, while roughly the size of our planet Earth, are circling very close to their star, giving them fiery temperatures that are most likely too hot to support life, researchers said. The discovery, however, brings scientists one step closer to finding a true twin of Earth that may be habitable. [<a href=http://www.space.com/13990-2-earth-size-alien-planets-kepler-smallest-worlds.html>Full Story</a>] <br><br>NEXT: UFO in Kansas? Not Quite
A few days ago, a "UFO" was spotted cruising down a main street in Cowley County, Kan. It wasn't in the skies, but instead being hauled on a flatbed truck driving down the middle of US Highway 77. [<a href=http://www.space.com/14011-ufo-spy-plane-kansas.html>Full Story</a>] <br><br>NEXT: Deep-Fried Planets
Astronomers have discovered two potential alien planets that apparently survived being engulfed by their bloated, dying parent star. <br><br>The discovery is a surprise to many scientists, as it had been widely believed that no planet could withstand such a thorough and intense scorching, researchers say. Also a surprise: The hardy alien worlds seem to have inflicted their own damage on the expanded star, stripping it of much of its mass. <br><br>"To our knowledge, there has been no previous case reported where such a strong influence on the evolution of a star seems to have occurred," said study lead author Stephane Charpinet, of the University of Toulouse in France. [<a href=http://www.space.com/14012-survivor-alien-planets-dying-star.html>Full Story</a>] <br><br>NEXT: Mercury's Mysterious Magnetic Field
The mystery of why Mercury's magnetic field is so weak may just have been solved: It is being stifled by the solar wind, researchers think. <br><br>First high-resolution image of Mercury transmitted by the MESSENGER spacecraft (in false color, 11 narrow-band color filters). First high-resolution image of Mercury transmitted by the MESSENGER spacecraft (in false color, 11 narrow-band color filters). CREDIT: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington View full size image The mystery of why Mercury's magnetic field is so weak may just have been solved: It is being stifled by the solar wind, researchers think. Mercury and Earth are the only rocky planets in the solar system to possess global magnetic fields, and for years scientists have puzzled over why Mercury's is so flimsy. Roiling molten iron cores generate magnetic fields, and given how extraordinarily iron-rich Mercury is for its size — its metallic heart may comprise two-thirds of Mercury's mass, twice the ratio for Earth, Venus or Mars — the innermost planet should have a magnetic field 30 times stronger than what spacecraft such as NASA's MESSENGER probe have detected so far. To study Mercury's magnetic field, researchers created 3-D computer simulations of the planet's interior and of the solar wind, the deluge of energetic particles from the sun that constantly bombards its nearest planet. <Br><br>The computer models suggested that the churning of Mercury's molten iron core ordinarily would amplify the magnetic field up to Earth-like levels, in a so-called dynamo process like the one within our planet. <br><br>NEXT: 'Space Ball' in Namibia
strange metal ball dropped out of the sky and slammed into the remote grassland of northern Namibia recently, according to press reports. <br><br>The 14-inch-wide (35-centimeter) metallic sphere hit the ground about 480 miles (750 kilometers) north of Windhoek, the African country's capital. It left a crater 13 inches (33 cm) deep and 12.5 feet (3.8 meters) across, the Agence-France Presse (AFP) reported Thursday (Dec. 22). [<a href=http://www.space.com/14028-namibia-space-ball-orbital-debris.html">Full Story</a>] <br><br>NEXT: Space-Flying Dutchman's Space Cheese
The first Dutch astronaut to return to space, André Kuipers returned to the International Space Station this week on a mission the European Space Agency named "PromISSe." <br><br>To prepare, Kuipers packed a special space watch, arranged to have Dutch cheese delivered in space and inspired stamps commissioned in his honor. [<a href=http://www.space.com/14035-dutch-astronaut-space-cheese-mementos.html">Full Story</a>] <br><br>NEXT: Rare Galaxy from 'Dawn of Time'
An ancient galaxy that formed just after the birth of the universe has been photographed by telescopes on Earth and in space, and is the brightest galaxy ever seen at such remote distances, astronomers say. <br><br>The blob-shaped galaxy, called GN-108036, is about 12.9 billion light-years away and appears as it existed just 750 million years after the universe began. The universe, for comparison, is about 13.7 billion years old. [<a href=http://www.space.com/14022-rare-galaxy-dawn-time-universe-photo.html">Full Story</a>] <br><br>NEXT: Earth Has Two 'Moons' Right Now
Earth has two moons, a group of scientists . One is that waxing and waning nightlight we all know and love. The other is a tiny asteroid, no bigger than a Smart Car, making huge doughnuts around Earth for a while before it zips off into the distance and is replaced by another. <br><br>That's the scenario posited by the scientists in a paper published Dec. 20 in the planetary science journal ICARUS. The researchers argue that there is a space rock at least 1 meter (3.3 feet) wide orbiting Earth at any given time, though it's not always the same rock. [<a href=http://www.space.com/14037-earth-2-moons-asteroids-theories.html">Full Story</a>] <br><br>NEXT: Astronauts Arrive at Space Station for the Holidays
Three astronauts arrived today (Dec. 23) at the International Space Station just in time for a zero gravity holiday party as they begin a five-month stay in orbit. NASA astronaut Don Pettit, Russian cosmonaut Oleg Kononenko, and Dutch astronaut Andre Kuipers of the European Space Agency (ESA), docked at the orbiting laboratory today at 10:19 a.m. EST (1519 GMT) as the two spacecraft sailed 240 miles over southern Russia. They arrived aboard a Russian Soyuz spacecraft, which launched Wednesday (Dec. 21) from Baikonur Cosmodrome in Kazakhstan. [<a href=http://www.space.com/14032-astronauts-arrive-space-docking-holidays.html">Full Story</a>] <br><br>NEXT: Russian Satellite Crashes in Siberia
A Russian communications satellite crashed just after liftoff Friday (Dec. 23) when its rocket apparently failed, the latest in a series of rocket launch failures for the country this year. <br><br>An unmanned Soyuz-2 rocket launched the Meridian military communications satellite from Plesetsk Cosmodrome in the Russian northern region. But the rocket failed to reach orbit, making it the fifth failed space mission for Russia in 2011. [<a href=http://www.space.com/14041-russian-satellite-crash-failed-rocket-launch.html">Full Story</a>]