Extrasolar Planet Discovery by Hubble

MeteorWayne · Nov 14, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>MeteorWayne thx for the reply, that makes sense, the hubble telescope time is extremely precious. I didn't state my question clearly, what I meant was whether it is even feasible to resolve the disc of that planet by a very long hubble exposure length. Or is it just too far away? Just wondering if we'd ever expect to see images of it or similar extrasolars as we see our own solar system planets. Posted by nightskybuff</DIV> Glad you made it over here.I don't think long exposures would lead to higher angular resolution (IOW seeing a disk). What it might allow is some spectrographic info, but I think even that is a long shot. I suspect a few pixels is the best we can get. But since I am not 100% sure, I'll do some checking and get back....but probably not until tomorrow since I will be concentrating on the shuttle launch tonight for the next 5 or 6 hours! <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-laughing.gif" border="0" alt="Laughing" title="Laughing" />Wayne <div class="Discussion_UserSignature"> But the Krell forgot one thing John. Monsters. Monsters from the Id. I really, really, really, really miss the "first unread post" function </div>

robnissen · Nov 14, 2008

There is a nice five minute video on the BBC web site describing Fomalhaut Bhttp://news.bbc.co.uk/2/hi/science/nature/7725584.stmI especially like the two pictures showing the movement of the planet.

MeteorWayne · Nov 14, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>There is a nice five minute video on the BBC web site describing Fomalhaut Bhttp://news.bbc.co.uk/2/hi/science/nature/7725584.stmI especially like the two pictures showing the movement of the planet. Posted by robnissen</DIV> To be honest, I wasn't too impressed with that. A lot of fancy CGI, and the two shots showing the motion were the same as the two combined in one image that was in the original release. Anything other than the original ring image, and the two shots of the planet were artist conceptions.I also wondered about the ESA label on it. Are any Hubble instruments from ESA?5 minutes spent with no new knowldge that wasn't in the original Hubble release...though I guess useful to interest the lay audience.Fluff for the unaware masses IMHO

<div class="Discussion_UserSignature"> But the Krell forgot one thing John. Monsters. Monsters from the Id. I really, really, really, really miss the "first unread post" function </div>

robnissen · Nov 14, 2008

I reckon I'm just an unaware mass that likes fluff.

nightskybuff · Nov 14, 2008

MeteorWayne, I figure you're very likely right. If it was that easy I'd imagine they would be planning exposures and there'd be news articles already about "upcoming" images. That would be huge news to have visible features of a plantary body in a solar system 25 light years away... People do love pictures... (including myself). Not that the nasa image of the fomalhaut system is anything to sneeze at.  But it sounds from the other (non-hubble) discovery that emerging optics techniques may pave the way eventually for glimpsing the mysteries of other star systems.  Thanks for your responses.

nimbus · Nov 15, 2008

It shouldn't be too complicated to calculate the maximum theoretical resolving power we should have now or in the near future and compare it to the resolving power required to see the closer exoplanets. <div class="Discussion_UserSignature"> </div>

OurUniverse · Nov 16, 2008

They should definately do this observation method on epsilon eridani! If they can? Its even closer at 10 light years and has the two asteroid belts and the Kuiper like belt! Also they found out that the planet(s) must have circular orbits because of the prescence of the asteroid belts i think? Anyone else thinking this too! <div class="Discussion_UserSignature"> </div>

MeteorWayne · Nov 17, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>They should definately do this observation method on epsilon eridani! If they can? Its even closer at 10 light years and has the two asteroid belts and the Kuiper like belt! Also they found out that the planet(s) must have circular orbits because of the prescence of the asteroid belts i think? Anyone else thinking this too! Posted by OurUniverse</DIV> It's quite likely such observations have already been done, without success. I'll see what I can find out.MW <div class="Discussion_UserSignature"> But the Krell forgot one thing John. Monsters. Monsters from the Id. I really, really, really, really miss the "first unread post" function </div>

3488 · Nov 17, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>It's quite likely such observations have already been done, without success. I'll see what I can find out.MW Posted by MeteorWayne</DIV>I've already tried to find requested observation Wayne, perhaps you'll have more luck.IMO, Epsilon Eridani will be a lot more difficult as Eps Eri is far less powerful then either Fomalhaut or even our own Sun. In fact Fomalhaut has approx 70 times the total luminosity of Epsilon Eridani, so although Epsilon Eridani is much closer, she star is much fainter as seen from Earth, so any planetary companions lit by the light from Epsilon Eridani will also be vastly fainter despite being much closer.Infrared imagery though, is likely to be more successful at this stage.View of Fomalhaut from approx 119 AU. <img src="http://sitelife.space.com/ver1.0/Content/images/store/10/1/3a51805a-772f-4b6e-812f-3236ae75115d.Medium.gif" alt="" />View of our Sun from Fomalhaut. The Sun is a magnitude 4.25 star within Leo Minor. Note how Leo appears distorted. Regulus is fainter & to the N E than as seen from the solar system & the hindquarters are squashed up, with Denebola noticeably further west. The star that has intruded into Leo's hindquarters, between Chort / Theta Leonis & Zosma / Delta Leonis on the end of the long line from bottom left is Alpha Centauri, faded to madnitude 3.76 & is 24.5 light years away.The two stars at right in front of Leo's distorted head are top Procyon, which has faded to magnitude 2.66 & is now 33 light years away, & the bottom newcomer to Leo is Sirius, now faded though still bright at magnitude 1.16 & is now 28 light years away. <img src="http://sitelife.space.com/ver1.0/Content/images/store/4/11/444a934b-e787-4d4a-ab4c-49053fff9295.Medium.gif" alt="" />Big Dipper / Plough as seen from the Fomalhaut system. <img src="http://sitelife.space.com/ver1.0/Content/images/store/0/8/802d2f64-76da-47ec-a866-710907febcd9.Medium.gif" alt="" />  Fomalhaut has some truly alien skies, despite not being far away cosmically speaking.. Andrew Brown.  <div class="Discussion_UserSignature"> "I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before". Linda Morabito on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.http://www.launchphotography.com/ http://anthmartian.googlepages.com/thisislandearthhttp://web.me.com/meridianijournal </div>

3488 · Nov 18, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>MeteorWayne thx for the reply, that makes sense, the hubble telescope time is extremely precious. I didn't state my question clearly, what I meant was whether it is even feasible to resolve the disc of that planet by a very long hubble exposure length. Or is it just too far away? Just wondering if we'd ever expect to see images of it or similar extrasolars as we see our own solar system planets. Posted by nightskybuff</DIV>Very big welcome nightskybuff to SDC.I second MeteorWayne's gladness that you made here also.Excellent first posts. Hubble time is very precious indeed. The Hubble team are literally inundated with requests, as would be expected. Many are just no hopers & will be rejected outright.Of the rest, worthy of more serious consideration, each will be  considered on a case by case basis.Reasons for rejections at this point would most likely be:1). Would take up too much observing time (after all Hubble can only observe for part of each orbit, & so called long exposure shots are stacked multiple exposures that effectively is ONE long exposure, such as Ultra Deep Field).2). Could be as effectively carried out by state of the art ground based observatories, i.e KECK, VLT, SUBARU, etc.3). Could be as or even more effectively carried out by other space based observatories, i.e SPITZER, GALEX, Chandra, etc with other spectral specialities.4). Not currently high priority, best suited for future space & or ground based observatories with greater light gathering & / or  faster processors (shorten the time to process said observations).  5). Something unexpected crops up, i.e Comet Shoemaker Levi 9 entering Jupiter's atmosphere, Comet 17/P Holmes flaring up, observing Martian weather in support of imminent spacecraft landings, i.e Mars Pathfinder, MERs & Phoenix Mars Lander. 6). Hubble is aging, the schedules are being lengthened for observations, so less slewing from target to target. After STS 125 Atlantis, Hubble will be back up to full strength & will be vastly more capable. So Hubble time is very precious indeed. Andrew Brown.  <div class="Discussion_UserSignature"> "I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before". Linda Morabito on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.http://www.launchphotography.com/ http://anthmartian.googlepages.com/thisislandearthhttp://web.me.com/meridianijournal </div>

robnissen · Nov 18, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>MeteorWayne thx for the reply, that makes sense, the hubble telescope time is extremely precious. I didn't state my question clearly, what I meant was whether it is even feasible to resolve the disc of that planet by a very long hubble exposure length. Or is it just too far away? Just wondering if we'd ever expect to see images of it or similar extrasolars as we see our own solar system planets. Posted by nightskybuff</DIV>I don't believe resolving the disk is within our current capabilities.  Only a handful of stars (I believe around 4, and not counting Sol) have been resolved to a disk, and they are all red super giants.  The first to be resolved was Betelgeuse in the late nineties and there have been a couple more since then.  Even the three stars of the Alpha Centauri system have not had their disks resolved and they are about six times closer than this extrasolar planet and orders of magnitude larger.

MeteorWayne · Nov 18, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>I don't believe resolving the disk is within our current capabilities.  Only a handful of stars (I believe around 4, and not counting Sol) have been resolved to a disk, and they are all red super giants.  The first to be resolved was Betelgeuse in the late nineties and there have been a couple more since then.  Even the three stars of the Alpha Centauri system have not had their disks resolved and they are about six times closer than this extrasolar planet and orders of magnitude larger. Posted by robnissen</DIV> An excellent point (or disk) sir!! <div class="Discussion_UserSignature"> But the Krell forgot one thing John. Monsters. Monsters from the Id. I really, really, really, really miss the "first unread post" function </div>

3488 · Nov 18, 2008

Piscis Australis above the English Channel, Dymchurch, Kent, UK. A shot I took during a trip to observe Comet 17/P Holmes.Monday 29th October 2007 @ 20:25 UTC. Fomalhaut is clearly visible here, despite being only about 10 degrees above the horizon. Little did I know, just over a year later, a giant planet would actually be confirmed orbiting this very young star. Unlabled view. Large 3.5 MB. Labled View.  Small 61 KB. Andrew Brown.  <div class="Discussion_UserSignature"> "I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before". Linda Morabito on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.http://www.launchphotography.com/ http://anthmartian.googlepages.com/thisislandearthhttp://web.me.com/meridianijournal </div>

UFmbutler · Nov 19, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>We know that a little less than 1% of solar type stars have hot Jupiters (semi-major axes less than 0.1 AU). The frequency depends quite strongly on metallicity, so as many as 2-3% of stars with more heavy elements than the Sun may have hot Jupiters, while very few stars with less heavy elements have hot Jupiters. So hot Jupiters aren't exactly the norm, but they aren't tremendously rare either. Most of the planets found to date are not hot Jupiters, the occurance frequency for planets actually increases with orbital period. So planets with longer orbital periods are more common (out to ~20 AU at least, we really don't know anything about the planet population beyond that, which is way the discoveries announced today are quite interesting). The radial velocity surveys find that something like 20% of all solar-like stars have a ~Jupiter-sized planet within 20 AU, while there are indications that smaller planets are more common. For more information have a look at: http://arxiv.org/abs/0803.3357 Posted by doubletruncation</DIV>You can't say that the frequency of hot Jupiters depends quite strongly on metallicity with much certainty.  There might appear to be a trend now, but keep in mind we only have a sample size of a few hundred, and a majority of the surveys are biased in some way.  I'm not entirely sure why you say the discovery frequency(assuming I understood you correctly) goes up with orbital period...that makes things harder to detect both with the radial velocity method and transit discoveries.  A massive planet at 0.1 AU is going to be much easier to detect than a similar mass planet at 5 AU.  If you mean detection via direct imaging, then yeah, you'd be right, but due to our current technology we are biased toward smaller separations.  The long period planets we have discovered are still pretty uncertain with regards to their orbital parameters.  Ideally, to constrain a planet well you need at least 2 full periods of RV observations, while for some of the known long period planets we only have maybe half of one period.   Although our current sample shows a preference toward certain planets, with new missions such as Kepler and Terrestrial Planet Finder coming, the rest of the "discovery space" should be filled up and I would imagine we will see a fairly even distribution.  The paper you linked to is written by the biggest names in exoplanets, but as my professor would say, "I'm dubious"(he studies exoplanet dynamics and statistics).  It is agreed upon that our sample of exoplanets is heavily biased, so I'm not sure why they would bother doing a statistical study at this point...  <div class="Discussion_UserSignature"> </div>

3488 · Nov 19, 2008

In fact low metallicity stars may favour Jupiter & Saturn type planets (assuming no silicate & metal cores) as they are mostly made from Hydrogen & Helium.These planets may not have large families of moons & / or rings, as these require heavier elements, nor these sytems have much in the way if at all of terrestrial planets.The debate of Hot Jupiters will rage on till we actually glimpse one & able to isolate its spectrum. Most favoured theory is that the 'Jupiter' was slowed by friction & pertabances from a circulsteller disk, causing it to spiral inwards. Its seems highly unlikely that they would have formed in their star hugging orbits.Regarding hot Jupiters per se, perhaps the metallicity of the star is imaterial, as the disk itself could be made of hydrogen & helium. Besides we do not really know how many of these Hot Jupiter's really exist & are actually real. Many coujld be observational errors or instead be something to do with the star. Upsilon Andromedae's Hot Jupiter is certainly genuine as it's IR signature has been identified & isolated. Need to check up on some of the others like 51 Pegasi, etc.Andrew Brown.  <div class="Discussion_UserSignature"> "I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before". Linda Morabito on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.http://www.launchphotography.com/ http://anthmartian.googlepages.com/thisislandearthhttp://web.me.com/meridianijournal </div>

UFmbutler · Nov 19, 2008

http://star-www.st-and.ac.uk/~kdh1/transits/kdhtransit/fig1.gifThis is kind of an ugly image, but it shows the "discovery space" I was referring to.  It also shows the parts of the plot that future missions are expected to "fill".  As I said before, I think it's really too early to say without a doubt that there is a correlation between metallicity and the resulting solar system.  There seems to be a trend that multiple planet systems(i.e. 55 cnc) have parent stars with higher metallicities(Fischer & Valenti 2005), but not all high metallicity stars have multi-planet systems, or any, detectable.  I think we should be careful with what we say...while it is certainly logical to expect high metallicities to correlate to more metal rich planets, we may find that isn't the case.  It would certainly not be the first time astronomy has thrown us a "curve ball".  I just don't like it when announcements are made to the public(see the previous 4 "detections" announced in the press prior to these two new ones) before we are certain we can make a claim...it tarnishes the reputation of astronomers in the eyes of the public.  <div class="Discussion_UserSignature"> </div>

Search

Extrasolar Planet Discovery by Hubble

MeteorWayne

Guest

robnissen

Guest

MeteorWayne

Guest

robnissen

Guest

nightskybuff

Guest

nimbus

Guest

OurUniverse

Guest

MeteorWayne

Guest

3488

Guest

3488

Guest

robnissen

Guest

MeteorWayne

Guest

3488

Guest

UFmbutler

Guest

3488

Guest

UFmbutler

Guest

Similar threads

TRENDING THREADS

Latest posts

Share this page