Comments on: ‘606 day http://oklo.org/2006/07/30/606-day/ characterizing planetary systems Thu, 18 Mar 2010 14:57:06 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: systemic - Countdown http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-3197 systemic - Countdown Mon, 20 Aug 2007 06:28:13 +0000 http://oklo.org/?p=115#comment-3197 [...] August 1st marked the most recent ‘606 day, which came and went without wide remark. Perhaps this was because in late Summer, HD 80606 rises and sets in near-synch the Sun, and is thus lost from the Earth’s night skies. [...] [...] August 1st marked the most recent ‘606 day, which came and went without wide remark. Perhaps this was because in late Summer, HD 80606 rises and sets in near-synch the Sun, and is thus lost from the Earth’s night skies. [...]

]]> By: systemic - blue moon http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-2558 systemic - blue moon Thu, 31 May 2007 02:00:46 +0000 http://oklo.org/?p=115#comment-2558 [...] At any rate, oklo.org’s latest recommendation is that you take off from work early tomorrow and have a few beers. It’s a good way to get ready for the next ‘606 day, which occurs at on Aug. 6th 2007 at 21:26 (UT). [...] [...] At any rate, oklo.org’s latest recommendation is that you take off from work early tomorrow and have a few beers. It’s a good way to get ready for the next ‘606 day, which occurs at on Aug. 6th 2007 at 21:26 (UT). [...]

]]> By: systemic - In the zone http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-2178 systemic - In the zone Mon, 16 Apr 2007 17:52:57 +0000 http://oklo.org/?p=115#comment-2178 [...] HD 80606b is a favorite here at oklo.org (see e.g. here). The planet went through periastron passage last week, and is now just on the verge of inferior conjunction with the Earth. The a-priori geometric odds of observing a transit are 1.6%. In 2005, transitsearch.org ran a campaign on the star, and while some useful photometry was obtained, the entire transit window was not covered. If HD 80606b happens to show central transits, then the duration of the event will be ~18 hours and the photometric depth will be ~1.4%. At any one location on Earth, one would be able to observe only the ingress or the egress. [...] [...] HD 80606b is a favorite here at oklo.org (see e.g. here). The planet went through periastron passage last week, and is now just on the verge of inferior conjunction with the Earth. The a-priori geometric odds of observing a transit are 1.6%. In 2005, transitsearch.org ran a campaign on the star, and while some useful photometry was obtained, the entire transit window was not covered. If HD 80606b happens to show central transits, then the duration of the event will be ~18 hours and the photometric depth will be ~1.4%. At any one location on Earth, one would be able to observe only the ingress or the egress. [...]

]]> By: Ghost in the Machine... « GEMSS: Global Exoplanet M-dwarf Search-Survey http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-1987 Ghost in the Machine... « GEMSS: Global Exoplanet M-dwarf Search-Survey Sat, 24 Mar 2007 19:17:39 +0000 http://oklo.org/?p=115#comment-1987 [...] I have been completely remiss in updating the goings-on here - my excuse it that it’s been pretty busy at work… Suffice it to say, we have some plans for narrowing the GEMSS search via space-borne, astrometric means…. more on that later…. We also have divergent irons in the fire to take a look at HD 80606, again, in a more pan-spectral fashion, and we are working up our results on the red dwarf GL 876, last reported in the visual, this time in the 3 and 7 mm bands (using the venerable VLA and ATCA instruments in 2005)… We were looking for debris and dust back then… But that’s not really GEMSS…. Promise, we’ll get relevant GEMSS thoughts out there soon! I also hear Dave Charbonneau is looking to begin a .3-m network, red dwarf search, too, as are the XO guys - good news! Also some great feedback from Chile…. Meanwhile, seems to be a good thread going on about GEMSS over at Centauri Dreams! Great to see the discussion! [...] [...] I have been completely remiss in updating the goings-on here – my excuse it that it’s been pretty busy at work… Suffice it to say, we have some plans for narrowing the GEMSS search via space-borne, astrometric means…. more on that later…. We also have divergent irons in the fire to take a look at HD 80606, again, in a more pan-spectral fashion, and we are working up our results on the red dwarf GL 876, last reported in the visual, this time in the 3 and 7 mm bands (using the venerable VLA and ATCA instruments in 2005)… We were looking for debris and dust back then… But that’s not really GEMSS…. Promise, we’ll get relevant GEMSS thoughts out there soon! I also hear Dave Charbonneau is looking to begin a .3-m network, red dwarf search, too, as are the XO guys – good news! Also some great feedback from Chile…. Meanwhile, seems to be a good thread going on about GEMSS over at Centauri Dreams! Great to see the discussion! [...]

]]> By: systemic - HD 118206… http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-1938 systemic - HD 118206… Sun, 18 Mar 2007 00:55:11 +0000 http://oklo.org/?p=115#comment-1938 [...] All of the planets observed so far with the Spitzer Space telescope have nearly circular orbits, and hence are at (or are very near) the spin-synchronous state. We’re waiting to hear the results of our Spitzer GO-4 application to observe the highly eccentric planet HD 80606b, during an upcoming ‘606 day. If our observing plan gets a thumbs-up, it’ll dramatically broaden the range of conditions under which planets have been observed. Very shortly, I’ll be posting the results of calculations that Jonathan Langton and I have been doing which predict what the light curve of HD 80606 should look like during the periastron passage in the various Spitzer bands. Here’s a sneak preview of how the temperature distribution on HD 80606b might appear as seen from a direction consistent with our line of sight from the Earth: [...] [...] All of the planets observed so far with the Spitzer Space telescope have nearly circular orbits, and hence are at (or are very near) the spin-synchronous state. We’re waiting to hear the results of our Spitzer GO-4 application to observe the highly eccentric planet HD 80606b, during an upcoming ‘606 day. If our observing plan gets a thumbs-up, it’ll dramatically broaden the range of conditions under which planets have been observed. Very shortly, I’ll be posting the results of calculations that Jonathan Langton and I have been doing which predict what the light curve of HD 80606 should look like during the periastron passage in the various Spitzer bands. Here’s a sneak preview of how the temperature distribution on HD 80606b might appear as seen from a direction consistent with our line of sight from the Earth: [...]

]]> By: systemic - …and then the clouds lifted http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-1009 systemic - …and then the clouds lifted Wed, 31 Jan 2007 01:19:25 +0000 http://oklo.org/?p=115#comment-1009 [...] In either event, during the time surrounding ‘606 day, the atmosphere will be too hot for water clouds, and so the albedo will be low when the planet is close to the star. Therefore, if Q is low, there’ll be a smooth variation in the reflected light from the planet over the course of an orbit. On the other hand, if Q is high, then there’ll be a sharp (and potentially observable) drop in the reflected-light signal as the clouds flash to steam. [...] [...] In either event, during the time surrounding ‘606 day, the atmosphere will be too hot for water clouds, and so the albedo will be low when the planet is close to the star. Therefore, if Q is low, there’ll be a smooth variation in the reflected light from the planet over the course of an orbit. On the other hand, if Q is high, then there’ll be a sharp (and potentially observable) drop in the reflected-light signal as the clouds flash to steam. [...]

]]> By: systemic - 300B http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-981 systemic - 300B Wed, 24 Jan 2007 17:05:32 +0000 http://oklo.org/?p=115#comment-981 [...] The 200-odd extrasolar planets that have been discovered with the radial velocity method are orbiting stars that lie within a few hundred light years of the Sun. The light we now see coming from GJ 876 left that red dwarf back in early August 1991. When you’re in the bars drinking to celebrate the periastron passages of HD 80606 b, it’s easy to forget that last December’s periastron passage actually occurred in September 1817. [...] [...] The 200-odd extrasolar planets that have been discovered with the radial velocity method are orbiting stars that lie within a few hundred light years of the Sun. The light we now see coming from GJ 876 left that red dwarf back in early August 1991. When you’re in the bars drinking to celebrate the periastron passages of HD 80606 b, it’s easy to forget that last December’s periastron passage actually occurred in September 1817. [...]

]]> By: systemic - Watch the Skies http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-589 systemic - Watch the Skies Thu, 07 Dec 2006 07:06:31 +0000 http://oklo.org/?p=115#comment-589 [...] HD 80606 is looking more interesting all the time. I’m working on an interesting writeup of what we’ve been learning. It really has the potential to give us an unambiguous value for the radiative time constant appropriate to the atmospheres of hot Jupiters. The next ‘606 day is December 26th, and I’ll be sending out a circular to the transitsearch.org observers to get a definitive confirmation that it doesn’t transit. Here’s the promotional poster (inspired by the SAO Moonwatch program, while simultaneously attempting to achieve a retro cold-war-flying-saucers feel): [...] [...] HD 80606 is looking more interesting all the time. I’m working on an interesting writeup of what we’ve been learning. It really has the potential to give us an unambiguous value for the radiative time constant appropriate to the atmospheres of hot Jupiters. The next ‘606 day is December 26th, and I’ll be sending out a circular to the transitsearch.org observers to get a definitive confirmation that it doesn’t transit. Here’s the promotional poster (inspired by the SAO Moonwatch program, while simultaneously attempting to achieve a retro cold-war-flying-saucers feel): [...]

]]> By: systemic - Follow Ups And other items… http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-402 systemic - Follow Ups And other items… Tue, 17 Oct 2006 21:00:57 +0000 http://oklo.org/?p=115#comment-402 [...] We’re holding out hope, though, for Cassini-State 2. In that case, there are two angles t0 vary (the orientation of the pole in the orbital plane, and the viewing inclination) and so it may well be possible to dredge up a good fit to the data. After-the-fact parameter tweaking, however, is highly unsatisfactory! I’m looking very much forward to seeing more data sets like Ups And’s. HD 189733, in particular should give a very nice full-phase curve, and further down the line HD 80606 should be even more interesting. [...] [...] We’re holding out hope, though, for Cassini-State 2. In that case, there are two angles t0 vary (the orientation of the pole in the orbital plane, and the viewing inclination) and so it may well be possible to dredge up a good fit to the data. After-the-fact parameter tweaking, however, is highly unsatisfactory! I’m looking very much forward to seeing more data sets like Ups And’s. HD 189733, in particular should give a very nice full-phase curve, and further down the line HD 80606 should be even more interesting. [...]

]]> By: greg http://oklo.org/2006/07/30/606-day/comment-page-1/#comment-239 greg Wed, 02 Aug 2006 16:27:55 +0000 http://oklo.org/?p=115#comment-239 Hi Vincent, Thanks for pointing to the papers! It's true that this planet almost certainly owes its high eccentricity to the kozai effect. It's quite likely that the current eccentricity is lower than what it was when the Kozai mechanism was operating. Given the current state of the system, I'm wondering if there might be a way to tease out some information about the tidal Q. It's too bad this system doesn't transit, in which case we'd have the planetary mass rather than just Msin(i). best, Greg Hi Vincent,

Thanks for pointing to the papers! It’s true that this planet almost
certainly owes its high eccentricity to the kozai effect. It’s quite likely that the current eccentricity is lower than what it was when the Kozai mechanism was operating. Given the current state of the system, I’m wondering if there might be a way to tease out some information about the tidal Q. It’s too bad this system doesn’t transit, in which case we’d have the planetary mass rather than just Msin(i).

best,
Greg

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