17 January 2007
An unusual dwarf planet discovered in the outer Solar System could be en route to becoming the brightest comet ever known.
2003 EL61 is a large, dense, rugby-ball-shaped hunk of rock with a fast rotation rate.
Professor Mike Brown has calculated that the object could be due a close encounter with the planet Neptune.
If so, Neptune's gravity could catapult it into the inner Solar System as a short-period comet.
"If you came back in two million years, EL61 could well be a comet," said Professor Brown, from the California Institute of Technology (Caltech) in Pasadena.
"When it becomes a comet, it will be the brightest we will ever see."
http://news.bbc.co.uk/2/hi/science/nature/6268799.stm