2008: A Momentous Year in Spaceflight

This was a momentous year for spaceflight. It saw the launch of the world's most powerful gamma-ray telescope, the space station's largest room, India's first moon probe, and even a space tourist who happens to be America's first second-generation space traveler.

Here are the Top 10 stories of 2008:

10. The first second-generation space travelers launch

Richard Garriott, the son of former NASA astronaut Owen Garriott, became the first American second-generation spaceflyer to reach orbit when he launched aboard a Soyuz rocket in October. For a hefty $30 million, paid to the Russian Federal Space Agency through the private U.S. firm Space Adventures, Garriott booked himself a 10-day vacation on the International Space Station (ISS). During his stay Garriott conducted science experiments, educational outreach activities, and even brought aboard a flash drive loaded with records of humanity's greatest achievements, copies of the avatars in one of his games and digital versions of selected humans' DNA, including that of comedian Stephen Colbert, host of "The Colbert Report." By coincidence, Garriott flew to the space station while it was under the command of Russian cosmonaut Sergei Volkov, himself a second-generation spaceflyer and the son of famed cosmonaut Alexander Volkov. The two spaceflyers met in orbit and returned to Earth together in later October.

9. The most shuttle missions to fly in one year since 2002

NASA launched four space shuttle missions in 2008 ? and returned each of them safely back home. That's the most shuttle liftoffs since 2002, and especially noteworthy in the wake of the Columbia tragedy of 2003. This year's flights each delivered vital components to the ISS, including major contributions from Japan, Europe and Canada. And the year almost saw one more shuttle flight ? the final servicing mission to Hubble ? but that launch was delayed until 2009 because of glitches on the orbiting telescope. NASA currently plans to launch nine more shuttle missions before retiring the fleet in 2010. Six of those flights are scheduled for 2009.

8. Fermi Gamma-ray Space Telescope launches

Some of the cosmos' most puzzling phenomena ? supermassive black holes, dark matter and mysterious explosions called gamma-ray bursts ? may soon be more understandable thanks to NASA's Fermi Gamma-ray Space Telescope, which launched in June. The world's most powerful telescope for observing the universe in high-energy gamma-ray light, the observatory was originally called the Gamma-ray Large Area Telescope (GLAST), but was rechristened after Italian scientist Enrico Fermi once the telescope was up and running in space.

7. Europe's first cargo ship flies

The flotilla of space station-bound spacecraft had been static for the last nine years until a new ship was added to the ranks in March. Europe's Jules Verne Automated Transfer Vehicle was the first of a new fleet of unmanned cargo ships designed to ferry food and supplies to astronauts on the orbiting laboratory. After launching and docking at the station successfully, the vehicle perished as designed in a fiery plunge through the atmosphere back to Earth. The double-decker bus-sized spacecraft is due to be succeeded by at least four sister freighter ships.

6. The International Space Station turns 10

For the past 10 years the ISS has been serenely floating above us, steadily growing in size and hosting more and more scientific cooperation between nations. The $100 billion space station marked its 10th anniversary Nov. 20, a decade after its first room, the Russian-built Zarya module, was launched into space. Over the years the lab has grown from the equivalent of a studio apartment into a three-bedroom house, hosted about 165 visitors from 15 countries, and circled the Earth more than 57,309 times. In June the laboratory got its biggest addition yet, the tour bus-sized Japanese Kibo module. The stately space station is not yet complete, though ? eight of NASA?s remaining shuttle missions will deliver its remaining components by 2010.

5. Privately-developed Falcon 1 rocket finally reaches orbit

In a major milestone, the Space Exploration Technologies (SpaceX) firm successfully launched its Falcon 1 rocket in September, capping off the company's six-year effort to lift the first non-governmental rocket into space. Arriving on the heels of three consecutive failed launch attempts, the Falcon 1's success was no foregone conclusion. The liquid-fueled booster's liftoff from the Kwajalein Atoll in the Pacific Ocean proved that SpaceX's engineering is sound, and the company is on its way toward fulfilling its goal of offering low-cost commercial rocket launches. It took about $100 million to develop and test the booster, but future flights should carry an $8 million price tag or less, the company said. SpaceX is now preparing to launch its larger Falcon 9 rocket from Cape Canaveral, Fla., and is one of two firms to win a NASA space station cargo contract on Tuesday.

4. Indian probe orbits the moon

India's Chandrayaan 1 probe became the nation's first spacecraft to travel beyond Earth orbit when it arrived at the moon in November to begin a planned two-year mission. The vehicle carried a mini craft painted in the red, white and green pattern of India's flag that crash-landed at the moon's south pole, taking pictures on its way down. The achievement establishes India's growing space prowess and sets the stage for the country's planned future goals of starting a manned space program and landing a rover on the moon.

3. China conducts its first spacewalk

In another first for a nation building up its space program, Chinese astronauts carried out their country's first spacewalk in September. China launched three astronauts on the Shenzhou 7 mission, the nation's third manned spaceflight. Zhai Zhigang became the first Chinese spacewalker when he stepped out of his space ship wearing a new Chinese-made spacesuit. During his 20-miute foray into space, Zhigang retrieved a test sample of lubricant from outside the vehicle, and waived a Chinese flag at the camera that was broadcasting his feat live. The event marked an impressive technological achievement for China, only the third country after Russia and the United States to independently launch a person into space.

2. Robot safely lands farther north on Mars than ever before

NASA's Phoenix Mars Lander touched down on the red planet in May in the first successful Mars landing since 2004. The stationary spacecraft spent more than five months testing the arctic plains environment for signs of habitability by potential Martian life, and confirmed the presence of water ice below the ground. Phoenix touched down farther north on Mars than any lander before it, and delivered a treasure trove of images and experimental results from our neighboring planet. After its prolific research stint, the lander finally ran out of power on Nov. 2 due to decreasing sunlight caused by the arctic transition from summer to fall and light-obscuring atmospheric dust.

1. NASA's 50th anniversary

On Oct. 1 the National Aeronautics and Space Administration turned 50 years old, marking a half century of achievements in space exploration that many would have doubted were possible before its founding in 1958. While some people are still smarting over the continued absence of flying cars, most can recognize that NASA has come a long way since the days when Americans watched with envy as Sputnik flew overhead. We won the moon (and may be racing back to it all over again), built a fleet of reusable space shuttles, and worked with other nations to construct a continuously-occupied floating space station for scientific research. There have also been horrific tragedies along the way: the lives of the Apollo 1, Challenger and Columbia astronauts attest to the fact that those great achievements weren't attained without a price. But for all the heartbreaks, setbacks and even public boredom with NASA, Americans can't seem to give up the dream of space. Who knows what the next 50 years will bring?

• Timeline: 50 Years of Spaceflight
• Image Gallery: 50 Years of Spaceflight: The Road Ahead
• Stepping Forward: The Year In Spaceflight 2007