4. Felix Baumgartner's record-breaking jump
Austrian daredevil Felix Baumgartner broke the speed of sound in October by jumping from the edge of space. He got up there on a balloon, then stepped off a platform 24 miles high and landed soon after in the New Mexico desert.
Baumgartner wore a 100-pound pressurized flight suit and helmet. Without protection, his blood would have been vaporized because the atmosphere was so thin when he jumped. The temperature at his launch point was estimated at 70 degrees below zero Fahrenheit, if not lower.
In doing so, Baumgartner broke the record for highest jump that had been set in 1960 by Col. Joe Kittinger. As part of a U.S. Air Force mission, Kittinger fell from 102,800 feet. He was a consultant for Baumgartner's efforts.
5. Planet with four suns
You may recall a scene from "Star Wars" where Luke Skywalker looks out across the landscape of a planet called Tatooine, which had two suns. This year, amateur scientists discovered that in reality, there is a planet with not just two, but four, suns.
This planet, called PH1, is special for another reason: It's the first confirmed planet that the Planet Hunters group has identified. Planet Hunters is a citizen science organization, made of people just like you, who are combing through planet data. The group has also helped identify several planet candidates. Learn more at planethunters.org.
6. Nearby star has a planet
The closest planet we know of to Earth, outside of our solar system, was identified in October. This planet orbits a star called Alpha Centauri B. It's unlikely to harbor life, but there's hope that other potential planets in that area might be more hospitable to breathing creatures.
Of course, when we say "close," we mean 4 light-years, or 23.5 trillion miles, away.
About 800 planets have been confirmed to exist outside our solar system, in addition to nearly 2,000 planet candidates found with the Kepler mission.
7. Vesta becomes a 'protoplanet'
NASA's Dawn spacecraft helped scientists to determine that Vesta, originally thought of as an asteroid, is a "protoplanet." That means that its structure has a dense, layered body, and it orbits the sun.
What's the difference between a protoplanet and a planet? It appears that something interrupted the development of protoplanets, which aren't fully formed, so they don't quite make the cut as full-fledged planets.
8. Bye-bye, space shuttles
In 2011, we said goodbye to NASA's Space Shuttle Program. This year, we saw the four surviving orbiters making Earthly journeys -- whether flown or towed -- to new homes at museums and similar attractions.
Discovery is at the Udvar-Hazy Center at the Smithsonian Institution's National Air and Space Museum in Chantilly, Virginia. It flew on the back of a 747 from Kennedy Space Center. This is the most traveled of the space shuttles.
Enterprise is at the Intrepid Sea-Air-Space Museum in New York. This shuttle never actually went into space, but it was carried on a 747 jet from Washington to New York in June. It was originally designed as a prototype test vehicle.
Endeavour is at the California Science Center in Los Angeles, having flown from Kennedy Space Center on the back of a 747. To make room for it to be towed through the city, dozens of trees were cut down and traffic signs removed.
Atlantis is at the Kennedy Space Center in Merritt Island, Florida. It was the last space shuttle to go to space, and the last to come to rest this year. Unlike the other shuttles, which made flyovers in various parts of the United States, Atlantis moved only 10 miles, towed by land to the Kennedy Space Center Visitor Complex in November.