Wikipedia:WikiProject Astronomy/Image Review

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=== [[Gliese 581 c]] ===
Image needed of a rocky planet, ~1.5x earth radii, 
dense atmosphere, orbiting a red dwarf star, 
with other planets in the system.~~~~

: I got this one, I can make it easily with Celestia. ~~~~

[edit] Requested images

[edit] Images under review

[edit] PSR B1257+12 and its 3 planets

Artist's impression of PSR B1257+12 (by NASA)

I love this picture artistically, but I wonder how accurate it is. Do pulsars really look like that? Rubble pile 21:30, 17 May 2007 (UTC)

I Am Not A Real Astrophysicist, But:

• The prominent loops in the picture might be sideways.
• If the light source is high-temperature blue, of course, then those sides of the planets should be lit the same color, not the generic white that artists seem to prefer. If we're imagining the color is being corrected, it should correct the pulsar color at the same time.
• The planets are Venus-and-Mercury-type distances apart. From the numbers on the pulsar's page, Planet A is too large in the picture, or B is too small. Depending on which it is, the "camera" could be either, uh, about .004 AU or .03 AU further out from the pulsar than Planet C. That would make the whole picture either maybe two degrees of arc across, or a quarter of a degree across. ... I think.
  (These are rough approximations based on the proportions in the picture and math done partially in my head.)
• The pulsar itself should look about .004%, that's 4×10^-5 as wide as the Sun does from Earth. The pulsar's page says its luminosity and temperature are unknown. With such a tiny point source, any luminosity might be believable. It could drown out the background stars in the picture, or not.
• On the other hand, this is a millisecond pulsar, which would need high-speed photography to catch detail like this. Can you get dim objects at high speed? To a human being, the pulsar would be a blurred propeller in the sky, or a pair of cones. My monitor flickers more slowly. Actually, given the speed of light, the pulsar would be a pair of conic spirals with hundreds of loops across the width of the picture.
  ... Unless all that blue junk is just supposed to be some kind of lens flare.

So, uh, probably this particular pulsar doesn't look like this. For an example of a real-world picture of a similar scale, I found a crescent Moon and a crescent Venus together in the same photo. Glycerinester 04:47, 18 May 2007 (UTC)

If you want, I can remove it. Fusion7 17:35, 2 June 2007 (UTC)

I dunno, it's probably better than nothing. It distinguishes the system from a more normal one. We could just post a call here for something better. Or find a real astrophysicist to confirm my suspicions. Glycerinester 21:55, 3 June 2007 (UTC)

[edit] Gliese 581 c

OK, I guess I'll bring it up again. Our old friend Gliese 581 c is still an invisible black-against-black in its own planetbox image.

It might be possible to munge something more useful out of the existing image e.g.
but maybe somebody would like to take a crack at an original work. Glycerinester 01:26, 28 May 2007 (UTC)

version 1 (telescopic view, 400x)

Thankfully the planet is large enough, and the star small enough, for a full disk and star to be seen together at the same time. Still too small though. Maybe should crop to show only part of the star? Sagittarian Milky Way 04:15, 28 May 2007 (UTC)

I think the astronomers and the artists should talk at some point about composition and balance and such design geekery. Blowing up the image to put most of the star out of frame might be a good idea here, as well as tilting the whole thing at an angle and maybe picking a viewpoint that leaves more space between the objects.

Remember the intended function of the image is to illustrate the planet, regardless of our ignorance of its details. If the image focuses the viewer's attention elsewhere, e.g. toward the star, its purpose is muddled. On the other hand, this one gets points from me for originality. It's definitely not what I expected. Glycerinester 04:49, 28 May 2007 (UTC)

version 2, partly finished

Sorry, I was just trying to make a pretty picture.

Anyway, this looks much better. No, the lines wouldn't be there in the final, I'm in the process of removing them. (On the other hand, I should just cut out an even bigger planet and paste it over that) Sagittarian Milky Way 06:15, 28 May 2007 (UTC)

"Sorry"? No, no, this is great. They're both great.

I was fussing with the first one myself.

Go SMW! Glycerinester 06:36, 28 May 2007 (UTC)

Yay! Isolate the non-star non-planet part and reduce brightness -127/-100%, plus contrast +57/+45% if you want the sky like I did it. Sagittarian Milky Way 07:34, 28 May 2007 (UTC)

I'm not sure about this approach. It's very attractive, but it risks being confusing to the non-scientific user: it makes the star look enormous and the planet very close to it, which is not the case. I do agree that the 'black-on-black' planet is too boring, but I find the present approach very misleading for this particular planet (it would be more appropriate for a genuinely close-orbiting planet, such as 51 Pegasi above). For Gliese 581 c, a crescent planet

Crescent Gliese 581 c, v.1

is less imaginative but more appropriate, especially since we have no idea what its surface looks like at all. That's just my opinion. Rubble pile 14:26, 28 May 2007 (UTC)

Would it be safe to include bodies of water in the rendering? So far, there is no evidence AGAINST it. (and it makes the image more appealing) Fusion7 18:14, 28 May 2007 (UTC)

The tidal locking would mean the water could only form around the terminator right? Debivort 18:26, 28 May 2007 (UTC)

True, but as you said, water could be depicted in that small strip. Anyway, in my opinion, there are two issues with the crescent image, one minor and the other one worth dealing with. First, having only a small sliver of the planet illuminated prevents key features of the planet, like the terminator and liquid water (if any). Second and more importantly, the image does not include Gliese 581 b, which orbits between Gliese 581 c and its sun. Fusion7 17:34, 2 June 2007 (UTC)

I'd say also, the composition draws the viewer's eye toward the star. It's barely better than the invisible-planet thumbnail on the article now. Glycerinester 04:36, 3 June 2007 (UTC)

Crescent Gliese v1 should be in png Sagittarian Milky Way 09:14, 4 June 2007 (UTC)

Well I hate to bring this up, but according to this page from the New York Time's website, Gliese 581 c may be too hot to support life as we know it. So, I think we should adjust the next image to fit that finding. Fusion7 15:34, 13 June 2007 (UTC)

[edit] Gliese 876

Image needed of the Gliese 876 planetary system. The system has three known planets. Fusion7 18:12, 22 July 2007 (UTC)