"Most distant' weather pictures"

[epicstruggle]

http://news.bbc.co.uk/2/hi/science/nature/6047626.stm

A Nasa space telescope has delivered the first weather forecast from a planet outside our Solar System.

The world, known as Upsilon Andromedae b, orbits close into a star that is 380 trillion km from Earth.

The Spitzer Space Telescope has been able to detect distinct day and night temperatures on the planet.

Ok, this is freaking exciting, I wonder how much more powerfull of a telescope we will need to actually look at surfaces of planets outside of this solar system.

epic

 

[nutball]

Ok, this is freaking exciting, I wonder how much more powerfull of a telescope we will need to actually look at surfaces of planets outside of this solar system.

Pretty damned powerful! TPF is aimed at imaging direct imaging of Earth-sized planets, though they'd be imaged pretty much as point sources, you'd not see detail on the surface. I'm not aware of any seriously proposed missions which aim resolve planetary surfaces (there are always ideas floating around but I don't think any have received much if any meaningful funding from either NASA or ESA).

The tough bit isn't just achieving the required spatial resolution. The light from these planets is swamped by that from the host star (which is maybe a factor of a million brighter). Imaging trying to see a cigarette lighter next to a floodlight in a football stadium. So you have to come up with an optical configuration which delivers the spatial resolution you need at the same time as blocking out the light from the host star (eg. a coronagraph).

In any case although direct imaging is very sexy and would without doubt be very interesting to the general public, until the resolution gets gets close to that we can achieve within our own Solar System it's not the best bang-for-buck from a scientific standpoint, especially given the cost. For now there's much more science to be had from obtaining spectra of the planets, this gives you information on composition for example, and would allow you to search for biosignatures.

 

[Guden Oden]

Wouldn't interstellar photography of planetary surfaces and the rather long exposure times needed to do so be defeated by the fact pretty much all planets rotate around their own axis?

A picture would therefore turn out pretty much as a swirl/blur, wouldn't it?

Maybe image processing could unswirl/unblur it to some degree if we knew the rate of rotation, but I would expect a lot of detail to be lost in the process...

 

[DemoCoder]

Bah, TPF is wimpy. NASA once had plans for a follow on to the TPF called the Terrestrial Planet Imager, which is 5 TPF's flying in formation plus a collector spacecraft, that's why, a total of 20 8-meter telescopes as one gigantic nulling interferometer capable of imaging remote planets with atleast a couple of dozen pixels. And it would be capable of detecting earth sized planets a factor of 10x-100x further than the TPF (e.g. 1000 lightyears out)

Also, they had the Terrestrial Life Finder, which is a TPF that images the spectra of atmospheres on detected planets to estimate their composition.


Maybe if we could stop having wars for a decade or two, we can spend more than a measely ~10-20 billion on space, and certainly alot more on space based astronomy, probes, and new propulsion concepts.

 

[nutball]

TPI is a pipe-dream in the current political climate I think (by which I don't mean the Iraq war, etc.). Even before Mr Bush chose to point NASA firmly at the Moon to the exclusion of everything else, missions on the (financial) scale of TPI were treated with a great deal of scepticism. An echo from "Faster, Cheaper, Worse" if you will. Furthermore any mission which relies on a constellation of spacecraft is very vunerable to incremental de-scope by the oversight committees.

Darwin aim(ed|s) to do spectroscopy. Given the commonality in goals and technology between TPF and Darwin there has been much talk about merging the two missions, but to be honest I haven't kept up to date on what the current status of that is. Collaboration between NASA and ESA often proves to be problematic.

 

[DemoCoder]

TPF is a pipe dream at the moment. The next JWST ain't even done yet, and you think 4 8-meter telescopes on a truss with lightpaths accurate to nanometers is going to get launched?

 

[nutball]

Yes. Well I think that one of TPF / Darwin / TPF-Darwin will get done. Will TPF be 8-metre telescopes? Perhaps not.

There are a number of space missions firmly in development which will require either very precise station-keeping and/or reconstruction of the inter-craft separation to ~wavelength of light. So I think it's a technology problem which will get solved. When? That I wouldn't like to say.

 

[rwolf]

I don't see what you have to gain by going to the moon again.

 

[Guden Oden]

Unsure what you mean. Are you thinking of gain in scientific, economic or perhaps cultural terms? All of the above?

It's hard to imagine a person whose mind is so limited absolutely NO gain whatsoever could be seen from venturing out from our so far only home planet. Apparantly, they do exist it seems.

 

[soylent]

http://news.bbc.co.uk/2/hi/science/nature/6047626.stm
Ok, this is freaking exciting, I wonder how much more powerfull of a telescope we will need to actually look at surfaces of planets outside of this solar system.

epic

They are usually not detected through observation of the planet at all, but of the star. By observing the doppler-shift of known emission lines one can discern star-motion due a planet. Change in relative velocity between the observer and star on the order of metres/s are resolvable(!).

Part of the problem of observing them is to observe a faint object right next to a star that's so increadibly brighter.

Currently, only HUGE planets at large distance from their host star are directly observable. And the result is less than magnificent.

http://www.newscientist.com/article.ns?id=dn6864
http://www.space.com/scienceastronomy/050401_first_extrasolarplanet_pic.html

 

[hey69]

cant they zoom in to MARS and take a closeup from those litle marscars they sended over ?

 

[DudeMiester]

Bah, TPF is wimpy. NASA once had plans for a follow on to the TPF called the Terrestrial Planet Imager, which is 5 TPF's flying in formation plus a collector spacecraft, that's why, a total of 20 8-meter telescopes as one gigantic nulling interferometer capable of imaging remote planets with atleast a couple of dozen pixels. And it would be capable of detecting earth sized planets a factor of 10x-100x further than the TPF (e.g. 1000 lightyears out)

Looking at that link, they say that the want to implement it by 25 years into the next century. By that I assume they mean 2125.