CyberWorld

Planetary science made some leaps and bounds in 2008 that many people weren’t even aware of. Many of the findings were right in our own backyards, in Mercury and Mars, and others were way out in space beyond our solar system. Astronomers discovered at least 50 new planets, called "exoplanets," this year. "It’s been a very exciting year for exoplanet discoveries," said Michael Liu, an astronomer at the University of Hawaii. "The big picture is that a wide variety of new technologies, both instruments on existing telescopes and new dedicated telescopes, are really allowing astronomers to do much more sensitive measurements, and thus leading to a real bonanza of discoveries," Liu told SPACE.com.

So far there have been more than 300 exoplanets discovered. Many astronomers seem convinced that it’s only a matter of time before they spot another planet Earth. In November, two teams of astronomers reported that they had taken photographs of exoplanets. Geoffrey Marcy of the University of California, Berkeley, calls the images "the most spectacular thing in 2008." Speaking about the Hubble Space Telescope’s image of the planet called Fomalhaut b., Marcy added, "In my own professional opinion this is by far the most definitive picture of a planet ever taken."

With the regular reports on NASA’s Phoenix Mars Lander, which touched down on the red planet in May, our planetary neighbor has gotten a lot of attention. There were also reports continuing to come from NASA’s Reconnaissance Orbiter and the Mars Exploration Rover twins Spirit and Opportunity. The Orbiter has not imaged nearly 40% of the planet, and continues to capture and send back fascinating pictures that help astronomers learn more about the planet.

One of the primary goals of these missions is to find signs of past or present water- the main ingredient for supporting life. When the Phoenix Lander collected water ice near the north pole of Mars this year, the astronomy world was overwhelmed. Earlier in the year, Spirit has found deposits of silica in Gusev Crater, which scientists believe suggests that hot water once flowed through the soil in hydrothermal vents, which may have harbored life. And if life did exist there at one time, the silica could have preserved fossils.

One of the most sci-fi sounding research projects of 2008 was the exploration of a mysterious "force" scientist call "dark energy." This force was discovered about 10 years ago and has been expanding the universe at an increasing pace. Scientists admit that their research is still in very preliminary stages, but a new method used this year confirmed the existence of dark energy and suggested that it is stifling the growth of galaxies. The basic concept is that in an expanding universe dominated by dark energy, rather than galaxies mixing and mingling, they fly away from each other.

Now that Pluto is no longer a planet, Mercury has taken its place as the smallest planet in our solar system. Mercury had remained cloaked in mystery until early 2008 when NASA’s Messenger probe made its first trek around Mercury, beginning a mission to take images of the entire planet. The first images indicated clear evidence of the existence of volcanoes. Pictures showed lava flows in the Caloris basin and a volcano larger than the state of Delaware. The thousands of other images sent by Messenger could shed light on other mysteries of Mercury, including the planet’s core, which makes up about 2/3 of the planet’s mass. Some astronomers purport that a huge impact hundreds of millions of years ago may have stripped Mercury of its original surface.

Astronomers predict that the upcoming year will bring us even closer to discovering a planet that could be Earth’s twin. NASA’s Kepler mission, scheduled to launch in March, will search for rocky planets about the size of Earth that orbit within the habitable zone of their host stars where liquid water and life may exist. While they continue their research, imaging, and postulating, the rest of the world can only watch and wait, gazing upward and dreaming of what might be out there.