Centauri's Thoughts

I posted yesterday about more objects out in the Kuiper belt and Oort cloud, and the increasing inclination:

The new object, temporarily named 2003 UB313, is about three times as far from the Sun as is Pluto. (97 AU)

"It's definitely bigger than Pluto," said Brown, a professor of planetary astronomy. The object is round and could be up to twice as large as Pluto, Brown told reporters in a hastily called NASA-run teleconference Friday evening.

His best estimate is that it is 2,100 miles wide, about 1-1/2 times the diameter of Pluto.

The object is inclined by a whopping 45 degrees to the main plane of the solar system, where most of the other planets orbit. That's why it eluded discovery: nobody was looking there until now, Brown said.

Some astronomers view it as a Kuiper Belt object and not a planet. The Kuiper Belt is a region of frozen objects beyond Neptune.

And this is just the beginning according to Alan Stern:

Next up: Mars-sized objects?

Alan Stern, of the Southwest Research Institute and leader of NASA's New Horizons mission to Pluto, predicted in the early 1990s that there would be 1,000 Plutos out there. He has also contended, based on computer modeling, that there should be Mars-sized worlds hidden in the far corners of our solar system and even possibly other worlds as large as Earth.

In a telephone interview after Friday's announcement, Stern, who was not involved in the discovery, said he stands by those predictions and expects Mars-sized objects to be found within decades.

"I find this to be very satisfying," Stern said of 2003 UB313. "It's something we've been looking for for a long time."

Stern stopped short of calling it one of the greatest discoveries in astronomy, however, because he sees it as just one more of many findings of objects in this size range. Last year, for example, Brown's team found Sedna, which is about three-fourths as large as Pluto. Others include 2004 DW and Quaoar.

Stern sees the outer solar system as an attic full of undiscovered objects.

"Now we have the technology to see them," he said. "We're just barely scratching the surface."

I'll be watching for more of these. Most are found by photographic comparison of patches of sky over a period of days, and the comet and asteroid hunters comparing pictures only 20 minutes apart.

The full article on Space.com is here