What you missed August 11th, if you didn’t catch the Marlborough Rotary clubs program J: Speaker Dr. Dawn Gelino, Scientist and Task Leader for Science Affairs at the NASA Exoplanet Science Institute, @ CalTech
Dr. Gelino took us on whirlwind tour of the universe while explaining why scientists are fairly certain that there are other “Earths” in our galaxy and others. In the words of Carl Sagan, “With ten billion trillion planets…it’s likely the universe is brimming with life.” Dr. Gelino began with what we know – our Sun with eight planets orbiting, and only one with life. But with 200 billion stars in our galaxy, and billions of galaxies…and they all have stars…it is easy to imagine other ‘earths’.
Stars are easier to see than planets; 564 planets have been found, but only four have been imaged. The Hubble Space Telescope helps us get sharper images of stars, but it takes getting rid of the starlight to see the planets.
‘Planet hunters’ as they are called, are detectives! They find most planets one of two ways. Did you know stars wiggle? They do if there are planets around them, exerting a gravitational pull. Now planet-hunting scientists look for stars that are moving, exhibiting the pull of orbiting planets. Or, they look for transiting planets, those crossing right in front of a star, blocking its light. Transiting planets are very rare, and it takes a lot of time and patience to ‘see’ them. The Kepler Mission has been staring at one patch of the sky for two years so far! It has found a system somewhat like our solar system…but it is very far away. To cross our galaxy it would take about 100,000 years traveling at the speed of light (which we cannot do yet.)
NASA funds all kinds of projects, including looking at the earth! The next big project, being developed now, is the James Webb Space Telescope. It is the next generation, ‘window on the universe’ for all of us and depends on our government’s commitment to space exploration. To find out more about NASA and the NASA Exoplanet Science Institute, go to http://planetquest.jpl.nasa.gov/. Your explorations will take you out of this world!