Abundant Exoplanets, Black Holes Hiding in a Spiral Galaxy: Astronomy News Today

The American Astronomical Society’s (AAS’s) winter meeting is always a time when exciting discoveries in astrophysics are announced and this year does not disappoint.   Among the discoveries announced today are 461 additional exoplanet candidates and an image of a spiral galaxy hiding two black holes.

The exoplanet news is based on data from NASA’s Kepler space telescope.  The Jet Propulsion Laboratory (JPL) announced that 461 additional exoplanet candidates — planets circling other stars — have been identified, of which four are less than twice the size of Earth and orbit in their sun’s habitable zone where liquid water is a possibility.  The total number of exoplanet candidates is now 2,740.  Additional observations are needed to verify the data before they are confirmed as actual exoplanets.  Kepler looks for changes in the brightness of stars as planets cross in front of — “transit” — them.  It cannot actually directly image the planets. The 2,740 exoplanet candidates are orbiting 2,036 different stars; 467 of those stars have more than one planet.

JPL also manages the Nuclear Spectroscopic Telescope Array (NuSTAR) program which is looking for black holes.   In this image released today, NuSTAR images two black holes “lurking” inside a spiral galaxy.

 Image credit:  NASA/JPL-Caltech/DSS

The magenta dots are “blazing black holes” that were first observed by a different NASA x-ray space telescope, Chandra.  This image combines the Chandra and NuSTAR x-ray data with visible light imagery.  The galaxy is IC 342, or Caldwell 5, and is 7 million light years away.

NuSTAR also contributed to this new image of supernova remnant Cassiopeia-A, 11,000 light years away.

 Image credit:  NASA/JPL-Caltech/DSS

Blue is the highest energy x-ray light, provided by NuSTAR, while red and green are at the lower ends of the x-ray spectrum observable with NuSTAR, which overlap with Chandra.