Posted on 09/15/2006 7:19:34 PM PDT by SunkenCiv
Mu Arae is confirmed as only the second known extrasolar system with four planets (the other being 55 Cancri).
I see they still haven't found K-pax.
About the extrasolar multi-planet system around HD160691We re-analyze the precision radial velocity (RV) observations of HD160691 (mu Ara) by the Anglo-Australian Planet Search Team. The star is supposed to host two Jovian companions (HD160691b, HD160691c) in long-period orbits (about 630 days and 2500 days, respectively) and a hot-Neptune (HD160691d) in about 9 days orbit. We perform a global search for the best fits in the orbital parameters space with a hybrid code employing the genetic algorithm and simplex method. The stability of Keplerian fits is verified with the N-body model of the RV signal that takes into account the dynamical constraints (so called GAMP method). Our analysis reveals a signature of the fourth, yet unknown and unconfirmed, 0.5 Jupiter-mass planet in about 307 days orbit. In overview, the global architecture of the four-planet configuration recalls the Solar system. All companions of HD160691 move in close to circular orbits. The orbits of the two inner Jovian planets are close to the 2:1 mean motion resonance (MMR). The alternative three-planet system involves two Jovian planets in eccentric orbits (with e about 0.3), close to the 4:1 MMR, but it yields a significantly worse fit to the data.
Krzysztof Gozdziewski,
Andrzej J. Maciejewski,
Cezary Migaszewski
Mon, 14 Aug 2006
:')
Is he still living in San Francisco?!?
lol
Sigh, let's hope they don't go the way of Pluto. There one day, gone the next.
I think Kevin Spacey is from Tam-Pax.
Astronomy Picture of the Day 08-31-04
NASA | 08-31-04 | Robert Nemiroff and Jerry Bonnell
Posted on 08/31/2004 8:16:43 AM EDT by petuniasevan
http://www.freerepublic.com/focus/f-chat/1203737/posts
Researchers make sport of finding planets
Salt Lake Tribune | 15 Sept 2004 | Joseph B. Verrengia
Posted on 09/15/2004 1:18:07 PM EDT by balrog666
http://www.freerepublic.com/focus/f-news/1216830/posts
'Super Earth' Discovered at Nearby Star
Space.com | 8/25/04 | Robert Roy Britt
Posted on 08/25/2004 6:27:13 PM EDT by swilhelm73
http://www.freerepublic.com/focus/f-news/1199464/posts
U.S. Astronomers Spot Smallest Planets Yet Orbiting Nearby Stars, Trumping Europeans
AP | 8/31/2004 | Joseph B. Verrengia
Posted on 08/31/2004 3:31:43 PM EDT by Red Badger
http://www.freerepublic.com/focus/f-news/1204083/posts
http://www.aao.gov.au/local/www/cgt/planet/aat.html
Anglo-Australian Planet Search Team
15 Sep 2004 - AAPS announces five new extra-solar planets!
The five new planets include the first multiple planet systems detected by the AAPS, and three low-mass (ie Saturnian- or sub-Saturnian-mass planets).
The multiple planet systems include two planets detected around the star mu Ara (in the constellation of Ara "The Altar"). The inner planet has an orbital period of 645 days and a minimum mass of 1.7 Jupiter masses. The outer planet has an orbital period of 8.2 years and a minimum mass of 3.1 Jupiter masses. Both planets have quite eccentric (ie non-circular) orbits. These two planets were recently "joined" by a third inner (but very much smaller) planet in a 9 day orbit announced by Santos et al.
The three low-mass planets have all been detected with orbital periods of between 26 and 129 days, and minimum masses of between 0.16 and 0.4 times that of Jupiter. These low-mass planets are exciting to the Anglo-Australian Planet Search team because they all have small velocity amplitudes - that is the represent the detection of quite small "wobbles" in the parent stars due to these planets. Indeed at just 12 to 18m/s these results obtained from data streams stretching back to 1998, represent exactly the levels of precision that our search needs to attain to detect Solar Systems like our own around other stars via the orbital motion of a Jupiter-like planet in a Jupiter-like 12 year orbit. They give us confidence that in the next 6 years, if there are any "Solar System-like" systems amongst our 240 targets stars, we will find them.
Totally obnoxious ping plug. I'm outta here.
Gosh, I'm really sorry I pinged jwh_Denver into this topic.
Oh, wait -- I didn't.
We are doomed, I say, doomed!
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