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philippeb8
2019-Mar-27, 01:12 PM
Are we finally entering this new era?
https://phys.org/news/2019-03-gravity-instrument-ground-exoplanet-imaging.html


Regards,
philippeb8


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John Mendenhall
2019-Mar-27, 02:38 PM
Are we finally entering this new era?
https://phys.org/news/2019-03-gravity-instrument-ground-exoplanet-imaging.html


Regards,
philippeb8


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Beautiful.

The Backroad Astronomer
2019-Mar-27, 03:38 PM
In the infrared at the moment an​d probably can be used if the planets are fairly warm but really cool.

philippeb8
2019-Mar-27, 03:48 PM
Wow! That indeed is going to be the next ďastronomy boomĒ...!


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The Backroad Astronomer
2019-Mar-27, 04:36 PM
What would be really cool is when they can tell if there is shadow going across the planet being cast by a moon.

StupendousMan
2019-Mar-27, 04:45 PM
The picture in the linked article is an artist's rendition, not an actual image. The new instrument provided better spectra of the planet than a single telescope would, but made no pictures at all. The resolution of the 4 VLT is nowhere close to that needed to resolve extrasolar planets.

So, I would vote "no."

The Backroad Astronomer
2019-Mar-27, 05:09 PM
That is what my impression of this was they can see what planets atmosphere is made of but not an actual photo of the planet, the last point I made was just a wish.

philippeb8
2019-Mar-27, 05:13 PM
Yeah but weíre just a step away from making it happen!


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Swift
2019-Mar-27, 05:42 PM
Yeah but we’re just a step away from making it happen!

That would have to be an exceedingly big step, depending on what you mean by "it".

philippeb8
2019-Mar-27, 05:49 PM
That would have to be an exceedingly big step, depending on what you mean by "it".

Just laying back, visualizing and dissecting exoplanets with the Internet. Iím sure astronomers will be delighted as well.


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John Mendenhall
2019-Mar-27, 05:58 PM
The picture in the linked article is an artist's rendition, not an actual image. The new instrument provided better spectra of the planet than a single telescope would, but made no pictures at all. The resolution of the 4 VLT is nowhere close to that needed to resolve extrasolar planets.

So, I would vote "no."

In which case the shame is on Physis. Org for not plainnly stating that the image is artwork.

I expect better than this from a legitimate physics publication.

philippeb8
2019-Mar-27, 05:58 PM
Just laying back, visualizing and dissecting exoplanets with the Internet. Iím sure astronomers will be delighted as well.


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And running AI tools to detect extra-terrestrial lifeforms, etc.


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George
2019-Mar-27, 08:46 PM
The picture in the linked article is an artist's rendition, not an actual image. Thanks, I kept looking for something to clarify but the banding in the "image" seemed to favor some sort of image rendering, which would be a fantastic accomplishment. So fantastic that I crunched the size aperture to see what would be required assuming each band on the disk was about 900 km and, interestingly for 129 lyrs, the effective aperture with maximum resolution would be about 900 km. :) [Well, I did start with 1000km but that didn't quite fit the bill, and someone might care to check the math.]

ronin
2019-Mar-27, 09:06 PM
Very exciting.

But my excitement is diminished slightly by remembering in the early 90's plans to have an orbital version built and deployed by now.

Hornblower
2019-Mar-28, 02:25 PM
I agree that they were remiss in not making it clear that the image at the top is an artist's rendition of what the planet might look like. As I understand the article, the interferometer cleanly teased the planet's light out of the total and enabled getting a good spectrum. That spectrum yielded the bulk composition of the atmosphere. My guess is that the researchers developed a theory of what it would look like based on what we know about Jupiter.

philippeb8
2019-Mar-28, 02:32 PM
I agree that they were remiss in not making it clear that the image at the top is an artist's rendition of what the planet might look like. As I understand the article, the interferometer cleanly teased the planet's light out of the total and enabled getting a good spectrum. That spectrum yielded the bulk composition of the atmosphere. My guess is that the researchers developed a theory of what it would look like based on what we know about Jupiter.

So that means weíre very close to get a good snapshot of the real planet, no?


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slang
2019-Mar-28, 03:55 PM
So that means we’re very close to get a good snapshot of the real planet, no?

No. Just knowing what the atmosphere is mostly made of does not even come close to having a snapshot. Unless you have some other idea of what a snapshot is than I do.

philippeb8
2019-Mar-28, 04:26 PM
No. Just knowing what the atmosphere is mostly made of does not even come close to having a snapshot. Unless you have some other idea of what a snapshot is than I do.

All we need to do is to zoom in by a factor of 10x and weíll have a more precise image obviously.

So if we donít have a clear picture yet, my question is: how much efforts are required and how long will it take to accomplish this goal?


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glappkaeft
2019-Mar-28, 07:03 PM
All we need to do is to zoom in by a factor of 10x and weíll have a more precise image obviously.

The article is about a recording a spectrum of a planet. This has very little to do with imaging, a older spectra if HR8799e looks like this:

24109


So if we donít have a clear picture yet, my question is: how much efforts are required and how long will it take to accomplish this goal?

For that you need to define what a clear picture means. Is 32x32 px (like the moon image attached) at 129 ly enough?

24108

philippeb8
2019-Mar-28, 07:05 PM
The article is about a recording a spectrum of a planet. This has very little to do with imaging, a older spectra if HR8799e looks like this:

24109



For that you need to define what a clear picture means. Is 32x32 px (like the moon image attached) at 129 ly enough?

24108

Yes.


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Roger E. Moore
2019-Mar-28, 07:17 PM
I was surprised to see that the planet was illuminated from within, by its superhot interior. The storm-shredded clouds are lit from below.

John Mendenhall
2019-Mar-28, 07:27 PM
All we need to do is to zoom in by a factor of 10x and weíll have a more precise image obviously.

So if we donít have a clear picture yet, my question is: how much efforts are required and how long will it take to accomplish this goal?


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Phillipe, you are missing the point. That very nice and very misleading piece of artwork at the opening of the article has nothing to do with imaging the planet. The work being reported is spectroscopic, not imaging. It is very good work, but in my opinion the article does not report it properly.

glappkaeft
2019-Mar-28, 07:32 PM
Yes.

If my math is correct that requires a telescope with a resolution of about 0.0000007 arc seconds (1 arc second = 1/3600th of a degree). As a comparison Hubble has a diffraction limit of 0.05 arc seconds. A planet imaging telescope with that spec would have to be about 0.05/0.0000007 (around 70'000) times larger than Hubble. That is a telescope with an opening of 2'400'000 meters.

Hornblower
2019-Mar-28, 07:36 PM
The resolving power of the interferometer is enough to cleanly separate the planet and the star. That is a far cry from being able to resolve surface features on the planet.

philippeb8
2019-Mar-28, 09:07 PM
If my math is correct that requires a telescope with a resolution of about 0.0000007 arc seconds (1 arc second = 1/3600th of a degree). As a comparison Hubble has a diffraction limit of 0.05 arc seconds. A planet imaging telescope with that spec would have to be about 0.05/0.0000007 (around 70'000) times larger than Hubble. That is a telescope with an opening of 2'400'000 meters.

Oh I see. Thanks for the estimate.


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cjameshuff
2019-Mar-28, 09:28 PM
All we need to do is to zoom in by a factor of 10x and weíll have a more precise image obviously.

So if we donít have a clear picture yet, my question is: how much efforts are required and how long will it take to accomplish this goal?

They've managed to separate the spectra of the planet from the spectra of its star. The two objects are separated by 14.5 AU. An additional factor of 10x would only give them less contamination in their spectral data.

cjameshuff
2019-Mar-28, 09:30 PM
In which case the shame is on Physis. Org for not plainnly stating that the image is artwork.

I expect better than this from a legitimate physics publication.

Publication? phys.org is just a news aggregator.

John Mendenhall
2019-Mar-28, 10:27 PM
Publication? phys.org is just a news aggregator.

Then I expect better than this from a legitimate physics news site.

philippeb8
2019-Mar-28, 10:29 PM
Then I expect better than this from a legitimate physics news site.

Yeah it was misleading. Stuff like that just backfires so I donít know why they did this.


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George
2019-Mar-28, 10:39 PM
If my math is correct that requires a telescope with a resolution of about 0.0000007 arc seconds (1 arc second = 1/3600th of a degree). As a comparison Hubble has a diffraction limit of 0.05 arc seconds. A planet imaging telescope with that spec would have to be about 0.05/0.0000007 (around 70'000) times larger than Hubble. That is a telescope with an opening of 2'400'000 meters. If you had a magic wand that could make a perfect and large telescope in space and wanted to see that exoplanet as the human eye sees the Moon, then you would need an effective aperture of about 500km, using the diffraction limit equation of 1.22 x wavelength/ aperture dia. I used 550nm as the wavelength.

[Added: I failed to mention that that is for a Uranus sized exoplanet]

Jens
2019-Mar-28, 11:06 PM
Then I expect better than this from a legitimate physics news site.

Just to be clear, phys.org simply publishes press releases with illustrations provided by the institution. So I am certain that your beef is with the European Southern Observatory that put out the press release.

But to be perfectly honest, Iíve written press releases on astronomy that include artist images, and I donít think itís particularly uncommon. To be honest, the actual figures in the scientific papers are completely inaccessible to a non-specialist audience.


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Jens
2019-Mar-29, 01:25 AM
Just adding to my post now that I'm on my computer, here are two press releases on astronomy where we included illustrations that are just images of what things might look like based on data that is really not visually attractive at all.

http://www.riken.jp/en/pr/press/2019/20190101_1/

http://www.riken.jp/en/pr/press/2018/20181218_1/

For the second paper, if you look on arxiv (https://arxiv.org/pdf/1810.10732.pdf), you can see how non-interesting the figures are to a non-specialist.

I agree that it would be better to specify that the picture is just an artist's conception (as I did in the press releases), but in defense of phy.org, if you look at the press release on the ESO's own website (https://www.eso.org/public/news/eso1905/), it doesn't make it clear that it is artwork. I think they assumed that people would be able to understand that even without the disclaimer...

glappkaeft
2019-Mar-29, 03:04 AM
If you had a magic wand that could make a perfect and large telescope in space and wanted to see that exoplanet as the human eye sees the Moon, then you would need an effective aperture of about 500km, using the diffraction limit equation of 1.22 x wavelength/ aperture dia. I used 550nm as the wavelength.

[Added: I failed to mention that that is for a Uranus sized exoplanet]

I was assuming Jupiter sized (a factor of 2.5) which explains the difference.

1claire
2019-Mar-29, 03:44 AM
It is so pretty, change is indeed inevitable.

George
2019-Mar-29, 12:51 PM
I was assuming Jupiter sized (a factor of 2.5) which explains the difference. I was limiting the size to the visual size of the Moon, which is about 31 arcminutes, so using one arcmin for visual resolution, a Jupiter at 129 lyrs would require approx. a 225km effective aperture. The artwork, however, suggests greater resolution so larger aperture would be required, as you calculated.