Astronomers find 'home from home' - 90 light years away!

spaceref.com ^ | 3 Jul 03 | staff

[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.

[RadioAstronomer]

The goal is to BREAK the speed of light, WITHOUT getting fried.

GR and SR seems to be against this. :-(

[Aric2000]

There has to be a way, after all, we broke the sound barrier, there has to be a way to break the speed of light without the laws of physics kicking in and frying our behinds.

There HAS to be a way around it, it is just a matter of thinking it through, and now that we find out that gravity travels at the speed of light, my hopes for an FTL gravitic drive are shot to pieces.

Maybe if we figure out how to create a wormhole? and aim it of course.

[RadioAstronomer]

Maybe if we figure out how to create a wormhole? and aim it of course.

Way out of my league!!!!!

[Aric2000]

Out of mine too, but it is fun to think about it....

Stephen Hawking talks about wormholes in his the universe in a nutshell, I don't pretend to understand them, but it would be fun to create a wormhole that would take us from here to Alpha Centauri in a LOT less time then going straight across real space.

It's a weird concept, but I think that I get the gist, but the specifics are what kill me, start hitting me with those equations and I'm gone on the 2nd number.

I always thought mathematics just involved numbers, then they tossed in all those letters, and I get lost, sure C= speed of light, and e= energy, but man, put them all together in those equations and my mind and eyes go gaga...LOL

[Aric2000]

Many years ago, I had a freind who believed that ET's were visiting our planet, and were doing various unscrupulous things.

Where he came up with this, I have no idea, but he used to talk about "the greys" drive system on their ship. He said that they created a gravity well and pulled whatever space they wanted to go to, into the space they were in, so they were actually pulling the very fabric of space towards themselves, or folding it like you would a sheet, take one piece and then fold it over to another, you step over the crease, let the gravity field go, and POOF, you are, MANY light years from where you were, and did NOT break the speed of light.

This sounds kind of like Stephen Hawking Wormhole thingymajig!! LOL

Yes, the guy was a total loon, but I always remember that one little bit about the drive system, because it sounded feasible to me for some reason.

[RadioAstronomer]

I always thought mathematics just involved numbers, then they tossed in all those letters, and I get lost, sure C= speed of light, and e= energy, but man, put them all together in those equations and my mind and eyes go gaga...LOL

Smiles for my friend!

[Aric2000]

Time for me to get to bed, my mother is having her annual 4th of July bash tomorrow and I get to play cohost, will be a VERY long day, but it will be fun playing on the lake all day and most of the night.

Have a great 4th of July my freind.

Good night...

[BMCDA]

Heheeh, I also use one of their cases for my new computer. I just had enough of those other cheap cases where your hands looked afterwards as if you repaired a running lawn-mower.

Oh, and a happy 4th of July to y'all ;)

[BMCDA]

Another effect of both Jupiter and the Sun on the asteroid belt is a group of asteroids that both precede and follow Jupiter in its orbit by 60 degrees. These asteroids are known as the Trojans.

Yepp! Also known as Lagrange points L4 and L5, which are the two stable ones.
Here is a good link on the Lagrange points. And here is the math (PDF!!): http://www.physics.montana.edu/faculty/cornish/lagrange.pdf

However, I'm sure RA knew all this stuff already ;)

[Liberal Classic]

As interesting as it is to infer the existance of gas giants by the wobble of their parent stars, I hesitate to call this a home away from home since nothing can be inferred about any terrestrial planets that may exist in orbit. To my knowledge (which is admittedly lacking in some areas) we have only observed one planet directly, when it passed in front of its star relative to our position. The rest we see by measuring the osillations of a star and we can only measure the largest planets this way. Nothing is yet known about small terrestrial worlds like ours. Our small world wouldn't add a wobble that we could now measure from lightyears away, but we could infer Jupiter's and Saturn's pull. I think what this article boils down to is since this system has a gas giant in the middle, there might be rocky plantes closer in. Since we don't have a moonbase yet I'm nonplussed.

[exDemMom]

I think we need to send the liberals first, to make sure the new planet has a functioning welfare system and environmental regulations before the rest of humanity arrives. Or at least that's what we can tell them.

I really like that idea, more than I can express. How soon can we send them?

[PatrickHenry]

There has to be a way, after all, we broke the sound barrier, there has to be a way to break the speed of light without the laws of physics kicking in and frying our behinds.

The sound barrier is a poor analogy. We always knew that stuff moved faster than sound (light, for instance). The sound barrier was only an engineering problem -- preventing planes from shaking apart. Prior to that we broke the "horse barrier" and then the "wind barrier." All engineering problems. Humans are good at that.

The speed of light is a whole different stalk of bananas. I'm working on it in my garage (pronounced "guy-RAHGE").

[e_engineer]

I disagree. It is easier to detect the more elliptical orbits around other "suns" at this time.

This is what I am trying to understand.

Radial velocity is the technique used for detecting most extrasolar planets (transit detection is rare). I can understand how more a more massive planet will cause a larger shift in the stars radial velocity than a less massive planet in an identical orbit.

It is also apparent that a shorter period orbit would be detected more easily than a longer period orbit because the required observation time is shorter, and the planet exerts more pull on the star when they are close together.

This is where it gets messy: Two equally massive planets, one in a circular orbit, the other in an elliptical orbit with equal perihelia. The peak excursion in the stars radial velocity should be the same for both, but the period of the eccentric orbit will be longer, reducing it's detectability.

In addition, we can only detect the component of radial velocity along the line of sight to the star. As the semi-major axis approaches perpendicularity to the line of sight, detectability decreases.

What am I missing here?

[TaRaRaBoomDeAyGoreLostToday!]

Let's just hope there are no Clinton's on this mirrored planet.

[js1138]

...so they were actually pulling the very fabric of space towards themselves, or folding it like you would a sheet...

The folks in "Dune" folded space, but they were on drugs. I suspect this is the best hope we have at the moment for getting spaced.

[Aric2000]

LOL, indeed, well, maybe we can figure it out without resorting to some drug...

Cross our fingers anyway.

[liberalnot]

when do we move?

and can we leave hillary here?

[balrog666]

The speed of light is a whole different stalk of bananas.

But the speed of bananas is still within my capabilities.

[longshadow]

Fortunately, our reported lack of moral fiber can be remedied with a sufficient application of dietary fiber.

One should exercise great caution in this approach; I once heard the late Buddy Hackett explain that after being persuaded to try an unusually high fiber diet, he excreted wicker furniture for a week.

Of course, if you knew what Buddy Hackett was like, you'd know he didn't use the word "excrete."

[fnord]