On the Prowl for Planets

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An all-sky view of stars in our Galaxy – the Milky Way – and neighbouring galaxies, based on the first year of observations from ESA’s Gaia satellite, from July 2014 to September 2015.

File photo: An all-sky view of stars in our Galaxy – the Milky Way – and neighbouring galaxies, based on the first year of observations from ESA’s Gaia satellite, from July 2014 to September 2015. (ESA)

The successor to the highly successful Kepler planet-hunting satellite TESS (Transiting Exoplanet Survey Satellite) sent the first data down last week. TESS was launched April 18, and settled into orbit and sent its first data two weeks ago, a photo of near-Sun space containing 200,000 stars, many of which could be accompanied by at least one planet. Kepler looked at just one small region of sky; TESS will survey almost the entire sky, concentrating on about 20,000 stars where it’s expected to turn up as many as 10,000 new planets, many of which orbit stars we already know well.

TESS uses the newest, most accurate map of the Milky Way ever made, the Gaia Project map. The catalog that goes with the map contains the positions, distances, motions, brightness, and colors of more than 1.3 billion stars. Also provides the surface temps of about 100 million stars and the effect of interstellar dust on 87 million stars! TESS will use the map’s accuracy to pinpoint the stars it really wants to concentrate on. A project of the European Space Agency, Gaia was launched in 2013 on a five-year mission to map the Milky Way. It doesn’t orbit Earth but sits at a gravitational balance point of Earth moon and sun a million miles from earth.

The moon is near Saturn tonight and Mars Wednesday night. If you have a chance to see Mars through a telescope anywhere, do it since it looks quite large and good!

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