As 2008 comes to a close, NASA has published a short retrospective of the year's biggest advances and discoveries. Here's a look at the highlights.
10th anniversary of the ISS
This year marked the 10th anniversary of the International Space Station. The first piece of what would become the space station--the Russian-built FGB, also called Zarya--lifted off from Earth on November 20, 1998. The Zarya is pictured here after two weeks aloft, a shot taken from the approaching space shuttle Endeavour, which would deliver the second piece, the Unity module.
NASA made four trips to the ISS in 2008 to build out the station with new modules and hardware, increasing its size, volume, and scientific research capabilities, and famously deliveirng a new water recycling system.
Its mass is now more than 313 tons, with an interior volume of more than 25,000 cubic feet, comparable, NASA says, to the size of a five-bedroom house. The ISS now contains 19 research facilities.
Phoenix Mars Lander
NASA's Phoenix Mars Lander touched down on the Red Planet and completed its mission this year. The Phoenix landed on Mars on May 25 farther north than any previous spacecraft had landed. During its mission, the Phoenix took and studied soil samples, and shot more than 25,000 pictures of the Martian surface. NASA credits Phoenix with confirming the presence of water-ice in Mars' subsurface.
After shutting itself down due to lack of sunlight to fuel its solar-powered batteries, the Phoenix ceased sending data back to Earth on November 2, two months later than the project had been expected to run.
This is an artist's rendering of the lander on Mars.
Ares I rocket
In 2008, NASA passed a major hurdle on its journey back to the moon. NASA completed preliminary design review for its new Ares I rocket, which is planned to carry astronauts to the International Space Station, the moon, and out into the solar system beginning in 2015. It is the first time in more than 35 years that NASA has reached such a milestone for a rocket that will carry astronauts into space.
Ares I is a two-stage rocket configuration topped by the Orion crew vehicle and its launch abort system. It is designed to carry crews of four to six astronauts and has a 25-ton payload capacity.
This is an artist's rendition of Ares I in the vehicle assembly building at the Kennedy Space Center in Florida.
Arctic sea ice declines
For 30 years, NASA has used satellites to observe and record changes to sea ice. NASA and the National Snow and Ice Data Center at the University of Colorado say that in 2008, Arctic sea ice reached the second-lowest level recorded since satellite observations have been possible. The lowest point was recorded in September 2007.
"Based on what we've learned over the last 30 years, we know that the perennial ice cover is now in trouble," said Joey Comiso of NASA's Goddard Space Flight Center in Greenbelt, Md. "You need more than just one winter of cooling for the ice to recover to the average extent observed since the measurements began. But the trend is going the other way. A warming Arctic causes the surface water to get warmer, which delays the onset of freeze up in the winter and leads to a shorter period of ice growth. Without the chance to thicken, sea ice becomes thinner and more vulnerable to continued melt."
This map shows the extent of Arctic sea ice in August 26, 2008. The orange line shows the 1979 to 2000 average extent for that day.
Researchers using NASA satellites believe they solved the mystery of the Northern Lights this year. Data from five THEMIS (Time History of Events and Macroscale Interactions during Substorms) satellites indicate that the phenomenon is caused an explosion of magnetic energy a third of the way to the moon. The key to the aurora borealis, NASA says, is magnetic reconnection, or "stressed magnetic field lines that suddenly snap to a new shape, like a rubber band that's been stretched too far." This causes a burst of light and movement near the northern and southern poles.
This artist's concept shows the explosion of energy responsible for sudden increases in the brightness and movement of the Northern Lights.
New planet discovered
In November, astronomers announced they'd spotted a giant planet orbiting a star located about 25 light-years from Earth. The exoplanet, called Fomalhaut b, was found with images taken by the Hubble Space Telescope. It marked the first time astronomers have seen a planet orbiting a star outside our solar system.
The Fomalhaut system is in the constellation Piscis Australis or "Southern Fish." The discovery in the 1980s of an excessive amount of dust in the Fomalhaut system indicated it was a likely place for a planet to be found. The planet itself is estimated to be no more than three times Jupiter's mass.
Next-generation rocket engine
On May 8, 2008, NASA engineers wrapped up their first series of tests on the agency's next generation of rocket engine, the J-2X. The J-2X will power the upper stages of the Ares I and Ares V rockets, designed to carry astronauts and cargo to the International Space Station, the moon, and even Mars.
Part of the J-2X development process has been to test older J-2 engine components, which have been used in various missions dating back to the Apollo program in the 1960s. Data collected from those tests will be used to refine the J-2X designs.
NASA has more information about the Ares launch vehicles here.
In June, NASA was part of a team that received the Robert J. Collier Trophy, a prestigious aviation award given by the National Aeronautic Association. The award was presented to the Automatic Dependent Surveillance-Broadcast, a collective of public and private groups that includes researchers from NASA's Ames Research Center in Moffett Field, Calif., and its Langley Research Center in Hampton, Va.
The ADS-B team developed a system that gives pilots and air traffic controllers accurate traffic data, real-time displays, as well as access to weather and flight information services, and terrain maps. The system is based on Global Positioning System satellite information instead of radar. The Collier selection committee said, "implementation (of the system) will have a broad impact on the safety, capacity and efficiency of the national airspace system."
In this photo, NASA's Ames Center director, S. Pete Worden, receives the 2007 Collier Trophy from NASA's associate administrator for the Aeronautics Research Mission Directorate, Jaiwon Shin.
India's moon mission
In October, the Indian Space Research Organization launched the country's first lunar orbiter, the Chandrayaan-1. Aboard the Chandrayaan-1 are NASA's Moon Mineralogy Mapper and the Miniature Synthetic Aperture Radar, which are taking a survey of the moon's mineral resources, mapping its polar regions, and looking for ice deposits.
Often, the research conducted at NASA creates breakthroughs in unexpected fields. This year, swimmers broke world and Olympic records in droves, thanks in part to a cutting-edge swimsuit developed by Speedo. Swimmers wearing the company's LZR Racer suit, including Americans Michael Phelps and Natalie Coughlin, set dozens of world records at the Beijing Olympics.
Those two swimmers helped in the development of the suit, as did a few researchers at NASA's Langley Research Center. Langley has conducted tests for drag reduction of vehicles like aircraft and boats for decades. But Speedo asked them to use their low-speed wind tunnel to test potential fabrics and determine which would create the least amount of drag on a swimmer.
Here, NASA engineer Steve Wilkinson sorts through more than 60 fabrics Speedo sent for testing in Langley's low-speed wind tunnel.