Hubble spies close companion to Polaris
Posted: Wed, Jan 11, 2006, 5:52 AM ET (1052 GMT)
Astronomers using the Hubble Space Telescope said this week that they have seen for the first time a small companion star to Polaris. The existence of the star, named Polaris Ab, had been inferred through a detection of a gravitational wobble in Polaris, a supergiant variable star 430 light-years from Earth. The dwarf companion star had not been seen before now, though, because it orbits two billion kilometers from Polaris, a separation of less than 0.2 arcseconds as seen from Earth. Astronomers plan to observe Polaris Ab over the next several years to plot its orbit and determine the mass of Polaris itself. The discovery makes Polaris a triple-star system; a more distant dwarf companion, Polaris B, was discovered over 200 years ago.
Astronomers using the Hubble Space Telescope said this week that they have seen for the first time a small companion star to Polaris. The existence of the star, named Polaris Ab, had been inferred through a detection of a gravitational wobble in Polaris, a supergiant variable star 430 light-years from Earth. The dwarf companion star had not been seen before now, though, because it orbits two billion kilometers from Polaris, a separation of less than 0.2 arcseconds as seen from Earth. Astronomers plan to observe Polaris Ab over the next several years to plot its orbit and determine the mass of Polaris itself. The discovery makes Polaris a triple-star system; a more distant dwarf companion, Polaris B, was discovered over 200 years ago.| <<previous article | next article>> |
|
news in brief
|
|
|
|
news links
|
|
Saturday, September 12
US Space Command Should Always Be Led by a Guardian
Air and Space Forces Magazine — 12:42 am ET (0442 GMT) More hotels and roads? Here's how SpaceX could change the economy in Acadiana.
Acadiana (LA) Advocate — 12:39 am ET (0439 GMT) SpaceX to Get Weighting Boost in Nasdaq 100 After Rebalance
Bloomberg News — 12:38 am ET (0438 GMT) India needs to launch the space act it keeps scrubbing
The Times of India — 12:37 am ET (0437 GMT) Greek Astrophysicist Calls for European Space Autonomy
Greek City Times — 12:35 am ET (0435 GMT) |
