January 5

New view of Mercury

Cassini made the first of this year’s five scheduled close approaches to Titan, the largest moon of Saturn, at a distance of about 600 miles (950 km). It may get more shots at the haze-enshrouded moon, though, because NASA could extend Cassini’s mission, which is scheduled to end in July, beyond the planned four years.

January 14

MESSENGER, the first spacecraft to visit Mercury in more than three decades, made its first pass by the planet, flying within 125 miles (200 km) of its rocky surface. MESSENGER will enter orbit around Mercury in 2011.

March 12

Water squirts from Enceladus in a false-color view. (NASA/JPL/SSI)

Cassini flew just 30 miles (50 km) above Enceladus, the second-largest moon of Saturn. Scientists targeted the craft to fly through a jet of frozen water that is squirting from cracks in the moon’s crust, helping explain why Enceladus has liquid water beneath its icy surface.

April 9

India will launch Chandrayaan-1 (Hindi for “Moon craft”). During its two-year orbital mission, it will photograph the surface, chart the mineral composition of lunar rocks, compile a topographic map, and look for water at the lunar poles. It also will release a probe that will burrow into the surface.

May 16

The Gamma-ray Large Area Telescope (GLAST) is scheduled for launch. It will study some of the most powerful objects and events in the universe, including gamma-ray bursts, supernovae, and the disks of hot gas that encircle some supermassive black holes.

Phoenix landing on Mars. (NASA/JPL/U. OF ARIZ.)

May 25

Phoenix Mars Lander is scheduled to touch down in the northern plains of Mars. The lander will scoop up and analyze soil samples for water and the chemistry of life. It is expected to operate for about 90 days before it is encased in ice as autumn settles and the planet’s northern polar ice cap expands.

July 15

IBEX, the Interstellar Boundary Explorer, is scheduled for launch. It will probe the extent of the magnetic bubble that surrounds our solar system and its interaction with intergalactic space.

August 7

Space shuttle Atlantis is scheduled to launch on the final mission to repair and upgrade Hubble Space Telescope. The orbiting observatory will receive new cameras and other instruments, along with replacement gyroscopes, batteries, and other equipment. The mission should extend HST’s operational lifetime by several years.

October 31

Planck satellite. (ESA)

NASA will launch Lunar Reconnaissance Orbiter, the first mission in its quest to return astronauts to the Moon. The robotic probe will look for good landing sites, look for resources that future explorers might use, and study radiation around the Moon.

The European Space Agency will launch two astronomy satellites on one booster. Herschel will use the largest telescope ever launched into space, 140 inches (3.5 meters) in diameter, to study the infrared and millimeter sky, including distant galaxies and clouds of gas and dust that are giving birth to new stars. Planck (shown in an artist’s rendering at left) will map the afterglow of the Big Bang, known as the cosmic microwave background, to study the birth of the universe and the development of the first stars and galaxies.

December 1

Solar Dynamic Observatory, a satellite designed to study the Sun’s magnetic field and the interactions between Earth and the solar wind, is scheduled for launch from Cape Canaveral. The mission, part of NASA’s “Living With a Star” program, will provide new insights into space weather, which affects orbiting satellites, radio communications, ground-based power grids, and other modern technologies.

See also Explorations in 2007