Distant star plays 'peek-a-boo' with TAU astronomers

Astronomers see star some 50 light-years from Earth covered by celestial body in the solar system that belongs to the “family” of Pluto.

By JUDY SIEGEL-ITZKOVICH
Star galaxy nebula colourful 370 (photo credit: UCLA/JPL-Caltech/NASA/Reuters)
Star galaxy nebula colourful 370
(photo credit: UCLA/JPL-Caltech/NASA/Reuters)
A star some 50 light-years from Earth was seen by Tel Aviv University astronomers last week as playing “peek-a-boo.” It was covered by a celestial body in the solar system that belongs to the “family” of Pluto.
The rare event occurred on the night between Tuesday, March 4 and Wednesday, March 5 and seen at TAU’s Wise Observatory near Mitzpe Ramon.
The astronomers explained that this is similar to a solar eclipse in which the sun is covered by the moon, and a shadow falls on a small region of the Earth. The difference is that here the “sun” was a distant star, and the eclipse as created by an asteroid.
The possible existence of such a peek-a-boo phenomenon was suggested by the French astronomer Jean Lecacheax as part international cooperative effort called Planoccult, but his theory on its path and location was less accurate and resulted in the prediction of places where it would be visible at the western part of Europe up to Iran in the east.
The TAU scientists used two telescopes to simultaneously observe the covering of the star. On Tuesday night, the celestial body was covered around 10 p.m.
The larger telescope took pictures continuously every four minutes, while the newer and smaller telescope did so in the same area every five seconds, which increased the accuracy on when the covering and its conclusion would occur.
Dr. Shai Caspi and Dr. Noah Brosch each viewed the images of one telescope on a different computer screen. It was clear at a certain moment by watching both telescope images that one of the stars disappeared and then reappeared. The asteroid covered the star for 43 seconds.
The data obtained at the observatory is now being processed and compared to a similar event that occured in December 2013 from Reunion Island in the Indian Ocean. The TAU observation was the only one in the world in which the covering was measured with two telescopes simultaneously.