For some people, movies like Star Trek and Avatar describe not just a possible, but a probable reality. The idea that humans might race through space at warp speed seems quite plausible. Following with this reasoning, it is just a matter of time until someone will discover a way to make space tours a reality.
The discovery of planet CoRoT-9b, announced on March 18 in the journal Nature, makes space-voyaging even easier to imagine. The temperate, possibly earth-like planet is named after the space telescope satellite that first detected it, CoRoT, operated by the French space agency Centre National d’ Etudes Spatiales. While the newly discovered planet’s name may seem less romantic than, say, Venus, Jupiter, or Saturn, it accurately describes the special mission of the satellite telescope that found it: to detect “convection, rotation, and transits.”
Even for those people who aren’t space junkies, the discovery of this particular celestial body is an interesting development. It is one of the more than 400 extrasolar planets that have been discovered in the past 25 years. “It is very exciting,” said Avi Shporer, a postdoctoral fellow in the Department of Physics at UCSB and was one of the 60 scientists credited with confirming the existence of CoRoT-9b after it was first detected (or suspected) in 2008. “There have been fast developments. Usually in science things develop slowly,” Shporer added.
Certain things about CoRoT-9b make its discovery particularly exciting, according to Shporer. For one, the planet comes no closer to the star it orbits than 54 million kilometers, farther away than others they have studied. CoRoT “is not affected so strongly by radiation from its star,” Shporer said. In the case of other extrasolar planets, he said, the stars they orbit can produce such a great amount of radiation that observational data must constantly be adjusted to take this phenomena into account. In attempting to determine how a planet was created, how it has evolved, and what it is composed of, scientists have to factor in how radiation is affecting their results. Less radiation makes it easier to compile data on the planet. “It gives us a unique opportunity to test models,” he said.
CoRoT, the satellite telescope that found the new planet, did so by detecting a transit, explained Shporer. A transit occurs when a planet passes in front of a host star and blocks some of its light. A transiting planet can provide a wealth of information: When this type of eclipse occurs, scientists can identify the planet’s mass, diameter, density, and temperature.
The CoRoT telescope detected the planet by observing a small drop in flux as CoRoT-9b orbited its star. [Flux is “a measure of the amount of energy given off by an astronomical object,” according to about.com’s astronomical glossary.]
“It was a very small drop, one or two percent,” said Shporer. The planet was found to transit every 95 days. Scientists worked for more than a year to confirm the planet’s existence. “It (the planet) could have been another thing, another astronomical observation. Sometimes they can be similar.” Shporer added, “It takes a long time to gather observations.”
Scientists used ground-based telescopes to observe the planet at the times it was expected to be visible. In the case of CoRoT-9b, the transit—the time the planet is blocking light from its star—occurs about every 95 days. Even though scientists could predict when the planet could best be evaluated, they had to hope it was at night in their part of the world. With 60 scientists working together, it is hoped that “one of them will be able to catch it during the nighttime,” said Shporer.
Once scientists have taken images of the planet, these images have to be processed and applied to models. After painstaking observations and analyzing of data, scientists can then confirm the existence of a planet. That is why CoRoT-9b’s discovery was not formally announced until this March.
While no one really knows what the future holds for space travel, or the interesting things we might see, be assured that there are scientists looking up into space, wondering and asking questions. While some people may tend to shrug off the discovery of a new planet (after all, it’s just one in 400), CoRoT-9b is thought to be similar to planets in our solar system, especially Jupiter or Saturn. It’s fun to imagine the possibilities. And who knows, maybe someday we’ll get to find out what’s going on there.