Posted on 07/03/2003 10:22:13 AM PDT by RightWhale
Astronomers find 'home from home' - 90 light years away!
Astronomers looking for planetary systems that resemble our own solar system have found the most similar formation so far. British astronomers, working with Australian and American colleagues, have discovered a planet like Jupiter in orbit round a nearby star that is very like our own Sun. Among the hundred found so far, this system is the one most similar to our Solar System. The planet's orbit is like that of Jupiter in our own Solar System, especially as it is nearly circular and there are no bigger planets closer in to its star.
"This planet is going round in a nearly circular orbit three-fifths the size of our own Jupiter. This is the closest we have yet got to a real Solar System-like planet, and advances our search for systems that are even more like our own," said UK team leader Hugh Jones of Liverpool John Moores University.
The planet was discovered using the 3.9-metre Anglo-Australian Telescope [AAT] in New South Wales, Australia. The discovery, which is part of a large search for solar systems that resemble our own, will be announced today (Thursday, July 3rd 2003) by Hugh Jones (Liverpool John Moores University) at a conference on "Extrasolar Planets: Today and Tomorrow" in Paris, France.
"It is the exquisite precision of our measurements that lets us search for these Jupiters - they are harder to find than the more exotic planets found so far. Perhaps most stars will be shown to have planets like our own Solar System", said Dr Alan Penny, from the Rutherford Appleton Laboratory.
The new planet, which has a mass about twice that of Jupiter, circles its star (HD70642) about every six years. HD70642 can be found in the constellation Puppis and is about 90 light years away from Earth. The planet is 3.3 times further from its star as the Earth is from the Sun (about halfway between Mars and Jupiter if it were in our own system).
The long-term goal of this programme is the detection of true analogues to the Solar System: planetary systems with giant planets in long circular orbits and small rocky planets on shorter circular orbits. This discovery of a -Jupiter- like gas giant planet around a nearby star is a step toward this goal. The discovery of other such planets and planetary satellites within the next decade will help astronomers assess the Solar System's place in the galaxy and whether planetary systems like our own are common or rare.
Prior to the discovery of extrasolar planets, planetary systems were generally predicted to be similar to the Solar System - giant planets orbiting beyond 4 Earth-Sun distances in circular orbits, and terrestrial mass planets in inner orbits. The danger of using theoretical ideas to extrapolate from just one example - our own Solar System - has been shown by the extrasolar planetary systems now known to exist which have very different properties. Planetary systems are much more diverse than ever imagined.
However these new planets have only been found around one-tenth of stars where they were looked for. It is possible that the harder-to-find very Solar System-like planets do exist around most stars.
The vast majority of the presently known extrasolar planets lie in elliptical orbits, which would preclude the existence of habitable terrestrial planets. Previously, the only gas giant found to orbit beyond 3 Earth-Sun distances in a near circular orbit was the outer planet of the 47 Ursa Majoris system - a system which also includes an inner gas giant at 2 Earth-Sun distances (unlike the Solar System). This discovery of a 3.3 Earth-Sun distance planet in a near circular orbit around a Sun-like star bears the closest likeness to our Solar System found to date and demonstrates our searches are precise enough to find Jupiter- like planets in Jupiter-like orbit.
To find evidence of planets, the astronomers use a high- precision technique developed by Paul Butler of the Carnegie Institute of Washington and Geoff Marcy of the University of California at Berkeley to measure how much a star "wobbles" in space as it is affected by a planet's gravity. As an unseen planet orbits a distant star, the gravitational pull causes the star to move back and forth in space. That wobble can be detected by the 'Doppler shifting' it causes in the star's light. This discovery demonstrates that the long term precision of the team's technique is 3 metres per second (7mph) making the Anglo-Australian Planet Search at least as precise as any of the many planet search projects underway.
However, an Apollo crew brought some of them back and they were brought back to life after a few years on the Moon.
I think the point is that many of us have been freepers for five years or more and have never been on a pulled thread before. This is quite a shock.
Don't you think we ought to warn them first?
You are correct. When I got online this morning and saw the flame war going on, I knew where it was headed. I have conveyed my thoughts to others privately, and we are trying to do better.
Nice investment.
How about if the U.S. Treasury merely bulldozes about $20 billion into the middle of the desert and creates the world's largest bonfire?
There are a couple of problems with that.
Of all the creatures on earth, man is the most unadapted: he is neither fleet nor massive; he is not armored against the elements nor is he comfortable in repose except in lush meadow; he cannot leap above the slithering threats of the jungle or outrun the winds of the desert sky; he is morose, irritable and totally out-of-sorts in solitude and an outright bore in poor company; he is never satisfied save for a full belly and an empty groin and he just will never leave anything alone, no matter how good it may seem to another.
Oh yeah, and laying off the abuse button would help.
I've only used the abuse button once in five years, and that was several weeks ago, and only after an extended private discussion about what I found offensive.
I really try to avoid flame wars, but I am, after all, a sinner. I hope you will judge me by my future efforts.
But creatures quite unlike us might. They might wonder how we survive with such a weak source of gamma rays to illumine our marigolds.
Maybe what is needed is a let's-handle-our-quarrels-without-dragging-in-management-pact?
Deal?
Maybe what is needed is a let's-handle-our-quarrels-without-dragging-in-management-pact?
Deal?
We ARE growns-ups, right?
After all, politics is discourse.
Who needs a Intersellar Traffic Cop?..."Full Speed Ahead...Damn the Photons"...Warp 9.9999999998 ST/NG - 4.795 days to reach Andomeda Galaxy...I found the warp calulator. :))
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