Hunt For Shadowy Kuiper Belt Objects All Set

[zavvy]

<b>Hunt For Shadowy Kuiper Belt Objects All Set </b><br /><br />LINK<br /><br />An ambitious hunt for small, faint objects in the outer solar system is set to begin in the next few weeks. The project could shed light on the shadowy region and reveal the forces that shaped the early solar system.<br /><br />The project will target the Kuiper Belt, a ring of objects beyond Neptune left over from the formation of the planets about 4.5 billion years ago. Most of the 1000 Kuiper Belt Objects (KBOs) discovered since 1992 orbit the Sun at a distance 30 to 50 times further than the Earth.<br /><br />Based on their brightness, they appear to range from 100 to 1000 kilometres in width. Astronomers expect to see many more KBOs of smaller size - which probably formed through collisions - but these are difficult to detect because they reflect so little light. Only the Hubble Space Telescope has managed to turn up any - a few objects tens of kilometres wide.<br /><br />"Progress in this area is achingly slow," says Charles Alcock, director of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, US. "Most of the volume of the solar system is inaccessible to direct surveys."<br /><br />So, he and an international team of astronomers have devised an alternative scheme to search for small KBOs. Their plan is to look not for the objects' reflected light but for their shadows. They will use four 50-centimetre telescopes in Taiwan to study 3000 stars simultaneously in the hopes that one will be dimmed by the passing of an intervening small KBO.<br /><br /><br />Perfectly aligned <br /><br /><br />This method could detect objects as small as 3 km across at distances of 100 astronomical units - one AU being the distance between the Earth and the Sun, about 150 million km. But a KBO transit event would last less than a second, and any detection would be dependent on the star, KBO, and telescopes being

 

[serak_the_preparer]

Kuiper Belt Objects smaller than previously supposed:<br /><br />New observations help Kuiper Belt lose weight by David L Chandler (New Scientist)<br /><br />12 November 04<br /><br />LOUISVILLE - <i>Objects in the Kuiper Belt - the region beyond Pluto's orbit where many comets originate - may be much smaller than astronomers thought, according to observations made with NASA's Spitzer infrared telescope.<br /><br />The objects are so far away that even the most powerful telescopes only see them as faint specks of light. While their existence had been inferred decades earlier, the first one was only discovered in 1992. More than a thousand have been found since.<br /><br />Their distances from Earth can be determined very accurately by determining their orbits, but the only way to estimate their sizes and masses has been to make educated guesses about their reflectivity and density.<br /><br />Astronomers had assumed that their reflectivity, or albedo, was similar to that of comets, whose nuclei are very dark. Halley's comet, which was studied close up by the Giotto spacecraft in 1986, has an albedo of 4% and this had been taken as the standard value for Kuiper Belt objects (KBOs).<br /><br />But an object’s albedo can be calculated directly by measuring the amount of heat it radiates – its “far-infrared thermal emission”. This is because the object’s heat is directly related to the darkness of its surface, just as a dark pavement gets hotter in the sun than a lighter one.<br /><br />It took the power of the Spitzer telescope, which orbits above Earth’s atmosphere, to apply this method to the extremely faint and distant KBOs.<br /><br />A team led by John Stansberry at the University of Arizona is using Spitzer to conduct a survey of KBOs. The astronomers’ detailed calculations for an object called 2002 AW197 - thought to be one of the largest KBOs - found it to be much brighter than expected, with an</i>

 

[centsworth_II]

Oh, good. A thread composed entirely of pasted articles!<img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> </div>

 

[serak_the_preparer]

True, but what's wrong with pasted articles? Would you really prefer an uninformed opinion? Much of Uplink's bandwidth is wasted with material of that sort. Though I no longer contribute as I used to, I suppose I'm still one of those who likes the idea of Space.com serving as a kind of archive, an on-line resource for space and science.<br /><br />And in that spirit, old but still informative:<br /><br />Planetoid found in Kuiper Belt, maybe the biggest yet (California Institute of Technology News Release)<br /><br />February 20, 2004<br /><br /><i>Planetary scientists at the California Institute of Technology and Yale University on Tuesday night discovered a new planetoid in the outer fringes of the solar system.<br /><br />The planetoid, currently known only as 2004 DW, could be even larger than Quaoar -- the current record holder in the area known as the Kuiper Belt -- and is some 4.4 billion miles from Earth....<br /><br />The size of 2004 DW is not yet certain; Brown estimates a size of about 1,400 kilometers, based on a comparison of the planetoid's luminosity with that of Quaoar. Because the distance of the object can already be calculated, its luminosity should be a good indicator of its size relative to Quaoar, provided the two objects have the same albedo, or reflectivity....</i><br /><br />New Planet-Shaped Body Found in Our Solar System by John Roach<br /><br />October 7, 2002<br /><br /><i>Astronomers announced today the discovery of the largest object in the solar system since Pluto was named the ninth planet in 1930. The object is half the size of Pluto, composed primarily of rock and ice, and circles the sun once every 288 years.<br /><br />Named Quaoar (pronounced KWAH-o-ar), the object resides in the Kuiper belt, a region of the sky beyond the orbit of Pluto and about 4 billion miles (6.5 bill</i>

 

[alokmohan]

Good news for pluto .Of late it was losing dignity.