Will We Find Other Planets Like Earth?

The “fun” has begun for NASA’s Kepler spacecraft, says William Borucki, the mission’s science principal investigator. In other words, the spacecraft has started its search for other Earth-like planets. It will look in what are called the “habitable zones” of our galaxy—regions at distances from stars (like our sun) where the temperature allows possible lakes and oceans to exist. Water, it’s believed, is necessary to support primitive life.
For the next three and a half years, Kepler will look for signs of these other habitable planets by staring at more than 100,000 stars. If planets are orbiting a star, its brightness will dull when the planet crosses in front of it and partially blocks the light.
“If Kepler got into a staring contest, it would win,” says James Fanson, the mission’s project manager. “The spacecraft is ready to stare intently at the same stars for several years so that it can precisely measure the slightest changes in their brightness caused by planets.”
You can follow Kepler’s progress with its updates on Twitter. —Heather Wax

Telescope Launch Day Is Only a Week Away

Two new telescopes will launch next Thursday, and scientists are hoping to look deep into space to gain greater insight into the history and composition of the universe.
Researchers will use the Herschel Space Observatory, a huge infrared telescope, to study some of space’s coldest objects, searching for signs of organic molecules and traces of water. “We’ll be studying the full extent of chemistry in space and we hope to learn what types of organics are out there as a function of their distance from a star,” Ted Bergin, a University of Michigan astronomer, says of the Herschel mission. “And we want to understand the chemical machinery that led to the formation of these organics.”
Bergin will use the telescope to study the gas and dust around young stars, looking for organic molecules. Many scientists believe the ingredients needed for the emergence of life on Earth came from space in things like comets and meteorites. “The chemistry of space makes molecules that are the precursors of life. It’s possible that the Earth didn’t have to make these things on its own, but that they were provided from space,” Bergin says. “Most of the water in the solar system is not where we are, but further out in the solar system. Most theories suggest that the Earth formed dry and impacts from asteroids or other objects provided the water here.”
The other telescope, Planck, will map the oldest light we see—the afterglow of the big bang, which we today call the “microwave cosmic background radiation.” And it will do so more accurately than has ever been possible before. The hope is that the new information will give scientists a better idea of how the universe began and what its future will look like. —Heather Wax

Are Other Planets Like Earth Out There?

Last week, NASA launched the Kepler spacecraft, which is designed to look for other habitable planets in our galaxy. Since water, it’s believed, is necessary to support primitive life, the mission will look for Earth-size planets in the “habitable zones”—regions at distances from stars (like our sun) where temperatures allow water to stay liquid.
Are there lots of Earthlike planets in the galaxy or is ours unique? It’s too early to speculate, and it will take the mission at least three years to find and confirm the existence of planets like our own. “Even if we find no planets like Earth, that by itself would be profound,” says William Borucki, the mission’s science principal investigator. “It would indicate that we are probably alone in the galaxy.”
You can follow Kepler’s progress with its updates on Twitter. —Heather Wax

Expanding the Search for Extraterrestrials

This week came news from the American Geophysical Union meeting in San Francisco that scientists are broadening their search for extraterrestrial life to “super-Earths”—giant, cold, icy planets (very little like Earth, in fact) that are seen on the outskirts of about one-third of solar systems. In most cases, the search for life has involved looking for planets in another solar system’s “habitable zone,” the distance from a star that provides temperatures at which water stays liquid. But the scientists believe super-Earths, which are in the farther reaches of these solar systems, might have an internal heat source that allows liquid water to form under the ice.
“It turns out that if super-Earths are young enough, massive enough, or have a thick atmosphere, they could have liquid water under the ice or even on the surface,” says Scott Gaudi, a professor of astronomy at Ohio State University. “And we will almost certainly be able to detect these habitable planets if they exist.”
It’s too early to speculate on what kind of life (biologically simple? intelligent?) might be found on these super-Earths or other planets, but over on Counterbalance, systematic theologian Ted Peters (who, earlier this year, released the “Peters ETI Religious Crisis Survey of 2008”) speculates on the theological implications of possible contact with these different types of extraterrestrials, a branch of theology he calls “astrotheology” or “exotheology.” —Heather Wax

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