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Solar System Fossils Found By Hubble
segment writes "Astronomers using NASA's Hubble Space Telescope have discovered three of the faintest and smallest objects ever detected beyond Neptune. Each lump of ice and rock is roughly the size of Philadelphia and orbits just beyond Neptune and Pluto, where they may have rested since the formation of the solar system 4.5 billion years ago. The objects reside in a ring-shaped region called the Kuiper Belt, which houses a swarm of icy rocks that are leftover building blocks, or "planetesimals," from the solar system's creation. The results of the search were announced by a group led by Gary Bernstein of the University of Pennsylvania at a meeting of NASA's Division of Planetary Sciences in Monterey, Calif."
Contact: Steve Bradt bradt@pobox.upenn.edu 215-573-6604 University of Pennsylvania
Solar system 'fossils' discovered by Hubble Telescope
PHILADELPHIA -- Astronomers using NASA's Hubble Space Telescope have discovered three of the faintest and smallest objects ever detected beyond Neptune. Each lump of ice and rock is roughly the size of Philadelphia and orbits just beyond Neptune and Pluto, where they may have rested since the formation of the solar system 4.5 billion years ago. The objects reside in a ring-shaped region called the Kuiper Belt, which houses a swarm of icy rocks that are leftover building blocks, or "planetesimals," from the solar system's creation.
The results of the search were announced by a group led by Gary Bernstein of the University of Pennsylvania at today's meeting of NASA's Division of Planetary Sciences in Monterey, Calif.
The study's big surprise is that so few Kuiper Belt members were discovered. With Hubble's exquisite resolution, Bernstein and his co-workers expected to find at least 60 Kuiper Belt members as small as 10 miles in diameter -- but only three were discovered. "Discovering many fewer Kuiper Belt Objects than was predicted makes it difficult to understand how so many comets appear near Earth since many comets were thought to originate in the Kuiper Belt," said Bernstein, associate professor of physics and astronomy at Penn. "This is a sign that perhaps the smaller planetesimals have been shattered into dust by colliding with each other over the past few billion years." Bernstein and his colleagues used Hubble to look for planetesimals that are much smaller and fainter than can be seen from ground-based telescopes. Hubble's Advanced Camera for Surveys was pointed at a region in the constellation Virgo over a 15-day period in January and February. A bank of 10 computers on the ground worked for six months searching for faint moving spots in the Hubble images. The three small objects the astronomers spotted - given the prosaic names 2003 BF91, 2003 BG91 and 2003 BH91 - range in size from 15 to 28 miles and are the smallest objects ever found beyond Neptune. At their current locations, these objects are a billion times fainter than the dimmest objects visible to the naked eye. But an icy body of this size that escapes the Kuiper Belt to wander near the sun can become visible from Earth as a comet as the wandering body starts to evaporate and form a surrounding cloud. Astronomers are probing the Kuiper Belt because the region offers a window on the early history of our solar system. The planets formed more than 4 billion years ago from a cloud of gas and dust that surrounded the infant sun. Microscopic bits of ice and dust stuck together to form lumps that grew from pebbles to boulders to city- or continent-sized planetesimals. The known planets and moons are the result of collisions between planetesimals. In most of the solar system, all of the planetesimals have either been absorbed into planets or ejected into interstellar space, destroying the traces of the early days of the solar system. Around 1950, Gerard Kuiper and Kenneth Edgeworth proposed that in the region beyond Neptune there are no planets capable of ejecting the leftover planetesimals, so there should be a zone, now called the Kuiper Belt, filled with small, icy bodies. Despite many years of searching, the first was not discovered until 1992; nearly 1,000 have since been discovered from telescopes on the ground. Most astronomers now believe that Pluto, discovered in 1930, is in fact a member of the Kuiper Belt. Astronomers now use the Kuiper Belt to learn about the history of the solar system, much as paleontologists use fossils to study early life. Each event that affected the outer solar system -- such as possible gravitational disturbances from passing stars or long-vanished planets -- is frozen into the properties of the Kuiper Belt members that we see today.
If the Hubble telescope could search the entire sky, it would find perhaps a half-million pla
They are sending one to have a look around in 2006 but it will take a few years to get there.
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
The bad thing is that it is not 100%.
... because ... why? You want 100% of americans to appear clueless?
The US government readily admits that they've found no connections between Iraq and Al Qaeda - as do others.
it's in my head
Not remnants of the BigBang, remnants of the first days of our solar system.
The intresting part of the search was the discovery of lots of big icy rocks there compared to the relatively very low amounts of small ones.
Its not yet known why there is a lack of the small rocks..
First, creation of the solar system happened about 10 billion year later than the big bang. Second, planets do not just magically appear, they slowly form when smaller particles and rocks lump together because of either gravity or impact. Therefore small blocks of "ice" can be considered building blocks.
karma capped
This New Horizons mission was hit by a big funding cut early this year, although that decision has now been reversed. However it is still not certain that the mission is going to happen, which is a shame because this really is a mission to go where none has gone before...
karma capped
Uh, actually isn't the problem more that we're using geographic references to two-dimensional areas in descriptions of 3-dimensional objects? In other words, even we Americans (and I a Philadelphian, as a matter of fact) have to wonder how deep is Philadelphia??
* Please do not read my signature.
Actually, comets are considered building blocks of the solar system. That's why there's a large push from NASA and the ESA to send spacecraft to comets and land on them and/or gather samples from them. Here are a few links:
Stardust
Contour (failed)
Rosetta (to be launched)
The best way to predict the future is to invent it.
Some answers to posted questions from the one who did the research & wrote the press release:
How do we know these things came from our Solar System and not another one? The response about the directions of orbits is good; all the Kuiper Belt Objects (KBOs) and all the known planets orbit in the same direction around the Sun. Wouldn't happen if things were falling in randomly, so almost certainly reflects the rotation of the disk of gas & dust from which our solar system formed. Also, why would it be any easier to make a chunk of ice/rock around another star and have it accidentally caught be our star thousands of light years away, then to just make it around our star? There are grains of dust moving through our Solar System that appear to come from interstellar space, but no big chunks.
Another posts said that comets are the true fossils; in fact short-period comets (including the ones targeted by the spacecraft) are believed to be escapees from the Kuiper Belt. Comets are being evaporated by the Sun (that's why they look so big, they have clouds around them) and so they'll evaporate to nothing but rubble in 10,000 years or so. Not very long by astronomy standards. So there must be unborn comets in "cold storage" somewhere far from the Sun.
The New Horizons mission to Pluto & Kuiper Belt object(s) is alive & kicking. Our discovery means it will be a little harder to find a Kuiper Belt target for them to hit, but it should still be possible. There probably is a dust cloud associated with the Kuiper Belt (debris from collisions), which is doughnut-shaped, but this cloud is not very dense and won't be a threat to the spacecraft. Space is very empty, even in a "crowded" neighborhood like the inner Solar System.