'Super Earth' Discovered at Nearby Star

[meteo]

http://space.com/scienceastronomy/super_earth_040825.html<br /><br />I found this article very interesting. I couldn't help think about the day we find an earth size planet. Any other thoughts?

 

[drwayne]

I wonder what rule-of-thumbs there are for the lower mass limit of planet detectability versus range...<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[silylene old]

Actually it's more of a "Neptune" than a "super-Earth".<br /><br />The detected planet has a mass of 14 x earth. Neptune's mass is 17 x earth. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[mooware]

<font color="yellow">"The detected planet has a mass of 14 x earth. Neptune's mass is 17 x earth"</font><br /><br />...and quite toasty..<br /><br />

 

[yurkin]

<font color="yellow">Actually it's more of a "Neptune" than a "super-Earth".</font><br /><br />Super Venus<br />Its more of a Super Venus then a Neptune.

 

[mooware]

<font color="yellow">"Super Venus It's more of a Super Venus than a Neptune"</font><br /><br />Does it wear a cape and tights?<br /><br />

 

[jcdenton]

Reading that article, that planet seems more like a giant Mercury.<br /> <div class="Discussion_UserSignature"> </div>

 

[mooware]

That was actually my first thought. A giant Mercury..

 

[asuscreative]

is it possible that this is the rocky core of a gas giant that moved (from gravity interactions) closer to the star, and then got its gas blown off? would a gas giant be able to keep its atmosphere if it was that close to its star? anybody have an idea what kind of distance from the stars surface this planet orbits at?

 

[odysseus145]

<i>At 14 times the mass of Earth, the newfound planet -- circling a star similar in size and brightness to our Sun -- is about as heavy as Uranus, a world of gas and ice and the smallest giant planet in our solar system.</i><br />-http://www.space.com/scienceastronomy/super_earth_040825.html<br /><br />I could have sworn that neptune was the smallest gas giant.<br /><br />Uranus<br />Equatorial radius (km) 25,559 <br /><br />Neptune<br />Equatorial radius (km) 24,746 <br /> <br /> <div class="Discussion_UserSignature"> </div>

 

[silylene old]

<i>I could have sworn that neptune was the smallest gas giant. </i><br /><br />That's why I was the first to suggest it was more of a Neptune than an Earth (3rd post in this thread).<br /><br />How long do you think Neptune could keep its atmosphere if it orbited at Mercury's distance? Or half of Mercury's distance? <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[yruc]

I found the article very intersting. 1st suspected rocky planet found outside of our solar system. Smallest planet around a "normal" star to date. <br /><br />Advancements keep coming. Can't wait till they are able to find planets the size of mars or smaller. <br /><br />Yruc<br /><br />

 

[odysseus145]

<blockquote><font class="small">In reply to:</font><hr /><p><i>I could have sworn that neptune was the smallest gas giant</i><br /><br />That's why I was the first to suggest it was more of a Neptune than an Earth (3rd post in this thread). <p><hr /></p></p></blockquote><br /><br />I was commmenting on the incorrect assertion in the article that Uranus was the smallest of the gas giants. I apologize if it appeared that I reiterated your post. <div class="Discussion_UserSignature"> </div>

 

[thalion]

Actually, there is an article discussing this exact possibility on Space.com:<br /><br />http://www.space.com/scienceastronomy/shrinking_planet_030312.html<br /><br />Other astronomers have speculated on the possibilities of "super hot Jupiters" that may lose mass rapidly enough to be reduced to their rocky cores--if they exist.<br /><br />Here's a link to an abstract that you might find interesting:<br /><br />http://www.edpsciences.org/articles/aa/abs/2004/20/aaga161/aaga161.html<br /><br />I personally think this is an amazing discovery, even though its being a terrestrial planet is not a done deal. The fact that it's relatively nearby, and has two other planets that can help put constraints on the system, I think it's great news.

 

[igorsboss]

Assuming this was an inhabited class-M planet, would <font color="yellow">a surface gravity of 2.4 gee</font>be enough gravity to prevent the natives from constructing a spacecraft capable of achieving escape velocity?

 

[alokmohan]

Till nowwe dont have anything smaller in stock.So we may call it earth.

 

[silylene old]

If the crust were warm enough, then there should be good thermal circulation processes distributing heat between the core, mantle and surface. If the planetary composition contains a lot of radioactives, I would think it's possible there might be a lot of additional crustal heating from convection. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[thalion]

The estimation of an exoplanet's planet's surface temperature is complex, and fraught with many unknowns, like albedo and atmospheric absorption. There are several mathematical methods available, but none of them is perfect. <br /><br />In any event, the relationship between surface temperature and average distance is not linear, and a planet in a hypothetical 9.5 day-orbit is not actually as hot as one would expect from a straight extrapolation.

 

[titanian]

Here is a website in which one can calculate the estimated temperature on the surface of any planet around a star depending on its distance from the star, its albedo, the size of the star and the surface temperature of the star.It's been developed on the basis of the law of Stefan (hypothesis of dark body).You will note that the surface temperature of Sedna for instance, is well below -240°c on line with the scientific measurements.It doesn't take the atmospheric factor into account ( greenhouse effect).<br />Go to:<br />www.titanexploration.com<br />On the left frame, click on Astronomical programs.<br /><br />

 

[icedown]

<blockquote><font class="small">In reply to:</font><hr /><p><br />is it possible that this is the rocky core of a gas giant that moved (from gravity interactions) closer to the star, and then got its gas blown off<br /><p><hr /></p></p></blockquote><br /><br />I was wondering this myself. They say it's real close to the border between a gas giant and just a rocky planet. Is it possible that it was a gas giant at a point earlier but because of the core's mass being so close to the line, it was easier for the sun to "blow" the gas off?

 

[CalliArcale]

I'm reviving this thread for another super-Earth discovery. This one is 13 Earth masses, but has a temperature of -330 F. I'm not clear on how they know it to be Earthlike and not Jovian (it is as massive as Neptune, after all), but it's definitely different than the last super-Earth discovery. The star is half the size of our Sun (a measly red dwarf) and the planet orbits far away, making it very cold.<br /><br />New planet: Icy super-Earth dominates distant system <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[qso1]

Excerpt from SDC article:<br />It could be a rocky planet with a thin atmosphere, a sort of "super Earth," the researchers said today.<br /><br />Me:<br />I think the term super earth is meant to imply that as the smallest planet detected so far is Neptune sized...it could be seen as super earth sized. As the excerpted quote indicates, they are not saying its an Earthlike world other than being rocky.<br /><br />I'm looking to the day when an Earthlike world is announced. Especially if they can show it to be more Earthlike than Mars or Venus through spectroscopy or other means. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[paulanderson]

That previous "super-Earth" planet announced last January is about 5.5 times Earth's mass, but only perhaps twice the Earth's diameter, so a lot smaller than Neptune, according to at least one radio interview I heard on CBC radio here at the time (<i>Quirks and Quarks</i> science program) with one of the astronomers involved. I'd like to hear more about their estimates as to the diameter as well as just the mass.<br /><br />There are also the three or four previously found planets thought to be smaller than Earth, but orbiting dead neutron stars.

 

[qso1]

That would be interesting to find out, the diameters mass and such. I would like to think we could find something a lot closer to us as in Alpha Centauri or Tau Ceti.<br /><br />BTW very interesting link you posted. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>I'd like to hear more about their estimates as to the diameter as well as just the mass. <p><hr /></p></p></blockquote><br /><br />Well, if they're confident that it's terrestrial, they should be able to give at least a range of possible diameters, since it constrains the possible densities it could have. Neptune, for instance, has a density of a measly 1.64 g/cm^3, so it's quite vast at 17 Earth masses. Earth's density is 5.52 g/cm^3; I'd expect this object could be significantly denser, due to gravitational compression. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>