The Hubble space telescope has produced the clearest evidence yet that a solar system like our own is forming around another star. It has photographed two disks of dust, one inclined to the other, around one of the closest stars to the sun.
Astronomers studying the unique image of Beta Pictoris, 63 light years away, believe it contains at least one planet the size of Jupiter and possibly others like the Earth. They say our own solar system must have formed in a similar way which explains why the orbits of some planets are slightly skewed compared to the Earth’s orbit.
Astronomers knew that one disk of dust surrounded the star, which is in the southern constellation of Pictor. They have suspected for ten years that what appeared to be a kink in it was in fact a second dust disk inclined at about four degrees to the first.
The Hubble observation, made with the telescope’s Advanced Camera for Surveys, blocked out the star’s own light with a coronograph to cause an artificial eclipse. This removed the glare and allowed the faint disks to become visible. The secondary disk is visible out to 24 billion miles from Beta Pictoris and may extend even further.
Astronomers say that the best explanation for the observations is that an unseen planet, up to 20 times as massive as Jupiter, is in orbit within the second disk and sweeping up material from the first. Beta Pictoris is much younger than the Sun, twice as massive and nine times more luminous.
The international study, revealed in the Astronomical Journal, was led by David Golimowski of Johns Hopkins University in Baltimore. He said: “The finding suggests that planets could be forming in two different planes. We know this can happen because the planets in our solar system are typically inclined to Earth’s orbit by several degrees. Perhaps stars forming more than one dust disk may be the norm in the formative years of a star system.”
The camera used in the discovery stopped working last week and Nasa are currently trying to reactivate it.
Astronomers first suspected that Beta Pictoris was ringed with warm dust more than 20 years ago after a satellite detected more infrared radiation being emitted than expected.