High resolution photographs of exoplanets

[statisticsnerd]

I found a website that has pictures of exoplanets, but of course they all just look like colored blobs. I wonder if we have the ability to resolve details of the surface of these exoplanets to the point where you can make out land masses, oceans, and ice caps. It seems like you would just need a higher power telescope to do it.

Aren't we sending up a new telescope to replace the Hubble sometime soon? I wonder if it will be able to zoom in on them a bit more.

 

[T.Neo]

We don't nearly have that capability. It may be possible to resolve details on the surfaces of exoplanets using telescopes, but these are generally restricted to theoretical speculations.

 

[BruceJohnJennerLawso]

We don't nearly have that capability. It may be possible to resolve details on the surfaces of exoplanets using telescopes, but these are generally restricted to theoretical speculations.

I believe it was once speculated that you maybe could build a telescope like that on the lunar surface, lower gravity making huge structures a little easier, but it still would have a lot of unknowns. Making a mirror or lenses of extreme scales on the moon would be very tricky to do properly. (ie blemishes in the mirror)

Generally speaking, spectral analysis can tell us a lot more than brute-force magnification on extrasolar objects.

 

[DaveS]

Aren't we sending up a new telescope to replace the Hubble sometime soon? I wonder if it will be able to zoom in on them a bit more.

What you're thinking of is the long-delayed James Webb Space Telescope. And it is not a HST replacement as HST can see UV/Vis/NIR while JWST can only do N/IR.

 

[Andy44]

The ability to see continents and oceans on exoplanets does not currently exist, but there was a project, since canceled, that might've been able to do it. It was to involve a gigantic pinhole camera and two spacecraft; one with the pinhole & light shade, and the trailing vehicle with the sensor:

http://www.nasa.gov/vision/universe/newworlds/new_worlds_imager.html

 

[Kyle]

This technology and capability does not exist, however I wouldn't be surprised if it eventually did exist in our lifetimes at the rate exoplanet detection is going. If I were NASA, I'd place such an object as far away from the sun as possible.

 

[MattBaker]

If I were NASA, I'd place such an object as far away from the sun as possible.

Unlikely since such a telescope or however it's done must send back enormous data rates. IMHO L2 sounds like a far better place for space telescopes than something like a Mars/Jupiter orbit.

 

[Unstung]

What you're thinking of is the long-delayed James Webb Space Telescope. And it is not a HST replacement as HST can see UV/Vis/NIR while JWST can only do N/IR.

JWST is similar to Spitzer in the wavelengths it observes while Hubble focuses on visible light with little capability to see in infrared and ultraviolet light. This is the pipe dream for the future generation, flagship-class, general purpose space observatory.

ATLAST is more closely related to Hubble than JWST. Although the successor to JWST will be an improvement, JWST is theoretically capable of detecting the atmospheres of nearby transiting exoplanets.

However, both Hubble and JWST are flagship-class general purpose space observatories, so they share the same type of mission.

Unlikely since such a telescope or however it's done must send back enormous data rates. IMHO L2 sounds like a far better place for space telescopes than something like a Mars/Jupiter orbit.

The advantage of placing a telescope in the outer solar system is having the spacecraft orbit beyond the zodiacal cloud, if not also having a dimmer sun to deal with. However, the data transfer rate will be much slower, the telescope will take years to get to its destination, more fuel will be required, and astronauts will not be able to repair the spacecraft... hopefully all these issues will change in the future.

 

[martins]

The ability to see continents and oceans on exoplanets does not currently exist, but there was a project, since canceled, that might've been able to do it. It was to involve a gigantic pinhole camera and two spacecraft; one with the pinhole & light shade, and the trailing vehicle with the sensor:

http://www.nasa.gov/vision/universe/newworlds/new_worlds_imager.html

I read the article, but I don't really understand how this idea could be used to get the required resolution. As I understand it, a pinhole camera works on the principle that the apparent aperture of the pinhole (as seen from the imaging plane) is small compared to the apparent aperture of the imaged object, so that different points on the imaging plane see different parts of the object, thereby forming an (inverted) image.

They propose a pinhole of 10m diameter at a distance of 200000km, so aperture is atan(10/2e8). If you want to image an exoplanet of diameter 50000km at, say 10ly distance, its aperture is atan(5e7/1e17), which is significantly smaller. So how would this form an image? Does it involve some clever analysis of diffraction patterns, rather than just looking at a simple projection?

Edit: hang on, they talk about two pinhole/camera pairs, so I guess this has something to do with it. Long-baseline interferometry?