Well, it looks like Einstein knew what he was talking about, after all. Earlier this week, researchers at
NASA and Stanford released the findings from their six-year Gravity Probe B (GP-B) mission, launched to test Einstein’s general theory of relativity. To do so, engineers strapped the GP-B satellite with four ultra-precise
gyroscopes to measure two pillars of the theory: the geodetic effect (the bending of space and time around a gravitational body) and frame dragging (the extent to which rotating bodies drag space and time with them as they spin on their axes). As they circled the Earth in polar orbit, the GP-B’s gyroscopes were pointed squarely at the IM Pegasi guide star, while engineers observed their behavior. In the universe outlined by Einstein’s theories, space and time are interwoven to create a four-dimensional web, atop which the Earth and other planetary bodies sit. The Earth’s mass, he argued, creates a vortex in this web, implying that all objects orbiting the planet would follow the general curvature of this dimple. If the Earth’s gravity had no effect on space and time, then, the position of NASA’s gyroscopes would have remained unchanged throughout the orbit. Ultimately, though, researchers noticed small, but quantifiable changes in their spin as they made their way around the globe — changes that corroborated Einstein’s theory. Francis Everitt, a Stanford physicist and principal investigator for the mission, poetically explained the significance of the findings, in a statement:
“Imagine the Earth as if it were immersed in honey. As the planet rotated its axis and orbited the Sun, the honey around it would warp and swirl, and it’s the same with space and time. GP-B confirmed two of the most profound predictions of Einstein’s universe, having far-reaching implications across astrophysics research. Likewise, the decades of technological innovation behind the mission will have a lasting legacy on Earth and in space.”
The GP-B mission was originally conceived more than 50 years ago, when the technology required to realize the experiment still didn’t exist. In fact, the experiment didn’t actually get off the ground until 2004, when the satellite was launched into orbit 400 miles above Earth. After spending just one year collecting data (and an impressive five years analyzing the information), NASA has finally confirmed something we always quietly suspected: Einstein was smart. Head past the break to see a more in-depth diagram of how the GP-B gathered its data.
Continue reading NASA concludes Gravity Probe B space-time experiment, proves Einstein really was a genius
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SETI’s search for intelligent life in outer space may be on ice for the time being, but the search for alien planets that may possibly support life of some sort is now being bolstered by a number of new efforts. One of the latest is the so-called ExoPlanetSat nanosatellite developed by MIT and Draper Laboratory, which recently got the go-ahead from NASA’s Cubesat Launch Initiative and is now set to hitch a ride into space sometime in 2012. While not quite as “nano” as the SIM card-sized satellites that launched with the Shuttle Endeavor, the smaller-than-a-breadbox ExoPlanetSat is still pretty tiny by satellite standards, yet it packs all the necessary optics and technology required for what’s known as transit observation — that is, monitoring a star for decreases in brightness, which could indicate a planet passing in front of it. What’s more, while the launch of a single satellite is plenty to get excited about, the researchers hope that it lead the way for a whole fleet of similar nanosatellites that could greatly speed up the search for planets.
