by Timothy Grove, MIT
Is there life on other earth-like planets? What exactly are “dark matter” and “dark energy” and how have they shaped the universe? Only research in space can answer such questions.
The U.S. role in space has been significantly reduced in recent years. What captured the public’s imagination in this past year was the dramatic rendezvous with a comet—somewhere out past the orbit of Mars—by a European spacecraft. The mission was not only daring—it took a decade for the spacecraft to reach and match orbits with the comet—but also yielded important science: water on the comet is isotopically different from that on Earth, making it unlikely that comets were the source of Earth’s abundant water resources. This past year, too, India has placed a spacecraft in orbit around Mars with instruments that are as sophisticated as those used by NASA, and China has successfully launched a spacecraft that orbited the moon and returned safely to Earth.
But the secrets of our solar system are not the only mystery out there in space. Are we alone in the universe? A definitive finding of life elsewhere would galvanize public attention around the world. Space telescopes including the U.S. Kepler mission have identified over 1000 confirmed planets circling other stars in our galaxy. Of these, a dozen are close enough and of a size—up to about 1.6 times the mass of Earth—that they appear to be rocky planets like Ear0th and with densities and apparent compositions to match. Some of them appear to be at the right distance from their stars to have liquid water, and thus could in theory support life. A new U.S. space observatory focused on such planets, the Transiting Exoplanet Survey Satellite, is to be launched in 2017, if budget cuts do not delay it.
Timothy Grove is the Associate Department Head of Earth Atmospheric and Planetary Sciences, and the Cecil & Ida Green Professor of Geology, at the Massachusetts Institute of Technology.
Excerpted from The Future Postponed, Massachusetts Institute of Technology, 2015