Royal Astronomical Society Press Release
RAS PN 10/34 (NAM 19) 14 April 2010
Using four of the world’s largest telescopes, scientists have obtained the most detailed information yet from the regions around two young stars tens of light years away, finding compact discs of rocky and dusty material at distances comparable to that from the Earth to the Sun. Keele University astronomer Dr Rachel Smith will present the team’s results on Wednesday 14th April at the RAS National Astronomy Meeting (NAM 2010) in Glasgow.
The astronomers used data from the MIDI interferometer, an instrument that combines the infrared light from the 8-m diameter telescopes of the European Southern Observatory’s Very Large Telescope in Chile to simulate the performance of a single telescope with a mirror more than 100 metres across.
Two of the stars observed with MIDI are similar to our Sun – one is a little cooler and one a little hotter. The first, catalogued as HD69830, is an orange star with spectral type K0V and is thought to be about 2 billion years old (compared with the Sun’s age of 4.5 billion years). It lies in the direction of the southern constellation of Puppis, is around 41 light years from the Sun and is known to have three planets with masses comparable to Neptune. The second star, eta Corvi (in the constellation of Corvus and 59 light years from the Sun) is spectral class F2V, equivalent to a yellow-white colour, and is about 1.3 billion years old. Earlier observations hinted at discs of material around both stars. Cold material was confirmed around eta Corvi as it lies 22.5 billion km from that star and so was easier to spot.