Starship Asterisk*

I really like that effect where the northerly stars appear to draw circles around one point and the southerly stars appear to draw circles around another point. Is there some image (perhaps a previous APOD) that shows this the best it can be shown? Would you want to stand at the equator to take such...

Thanks, Chris and Nitpicker, for your replies. They strongly persuade me against the theory that it is a piece of human space junk, debris blown into the region. In particular, I did not realize that Opportunity was actually 20 km away from its landing site. Way farther than I imagined. Still, it ki...

I am wondering 2 things. How was a chemical analysis performed on the jelly-donut object ? If one of you can explain that to me I would greatly appreciate it. I wonder why nobody replied to one of the earliest comments in the thread: More likely to be a piece of the aging and decaying rover itself? ...

Are there any similar images (perhaps previous APODs) that show the maximum-sized and minimum-sized Sun? Is the relative difference less?

Nice image. And you contributors always bring out much more than I first realize is interesting. As the Earth and Moon rotate around a center of mass, I assume that when the Moon is full, the Earth is always closest to the Sun (a local minimum, that is). If the Moon is full at apogee, then if I unde...

Thanks to all of you. I think this was a very very brief intro to the apparently very involved topic the processing of astronomical images.

Tadpoles are amphibians. That's why this discussion is all about how they get oxygen. :D If I understand the APOD's intro description, then the blue I am seeing all over the image is from oxygen being very prevalent in this area? I don't see any green and very little red. That confuses me, because I...

Beautiful image. I liked starsurfer's characterization: "... glittering sapphires on the golden galactic beach". As usual, here's a post full of questions ... I assume the blue-ish stars are the cluster, and are at about 1000 light-years away, as the caption described. But around the core ...

Nitpicker: You should go correct the misspelling in the Wikipedia article that you noticed.

I'm assuming that one of the things that is easy to do with these nebula is to determine the rate of expansion of the bubble. There are lots of things that appear to be hard to directly observe in astronomy, but that one seems very straightforward. I mean, we can just image it twice, like 10 years a...

It's a beautiful picture. Looks a lot like a spider web with a captured moth wrapped up in the middle. http://bugguide.net/images/cache/HQARYK1RKQYQ20Q050K050CQM0BRHQARX0TQE0TRSQQ0N0JQG01R50NRLQFQI0Z0SQH0XQ3R0QS0N0L0N0K00Q00IQ.jpg Since Hubble is in space, I guess we don't need to go check the lens,...

Thanks for continuing to answer. There is just so much one can learn from you folks !
Here's another blown-up bit from that image. I took from pixel (1500,2100) for about 140w x 130h pixels.
Now that's what I call a constellation! I'd call it the serpent if I lived in the vicinity.

Cosmic rays, Mark. As in, they aren't actually objects. Cosmic rays are objects -- very tiny objects, and very far away from the stars in the globular cluster. :wink: Thanks. So, is this a limiting problem with all deep-space astronomy? What I guessed as "noise", is more accurately called...

Here's a naive question. But, if one has much to learn, one needs to ask, right? I took a piece of the image and downloaded it, then zoomed it in 4x. If you are interested, it is from almost the upper right corner of this APOD image. ZoomedCropped.jpg I see one nice bright blue star, and many smalle...

Pretty unlikely, I know, but what if the axis of rotation of the star and the BH were at right angles, with one BH pole pointing INTO the star? What if the iron originates in the BH's accretion disc, from lighter elements extracted from the star's outer layers? Then the jet would recirculate the ir...

Thank you sirs for the additional info. And I'm wondering about posting images. It appears that if I want to post an image in this discussion, I need to place it on a web server. Of course, as a typical contributor, I will probably drop or move the image after a time. So, it will eventually vanish f...

Thanks to all of you for the answers to several of my questions. Based on Chris Peterson's advice, I plotted a 166-pixel diameter white disk about where I'd guess the sun was. http://permaconnect.net/mark/SaturnBacklit.jpg (I am partly just wondering if I can plot an image in this way.) I don't have...

I think this is a really marvelous picture. But after just enjoying it a bit, and then reading this discussion, I have some questions. How large is the disk of the Sun and where would it fall in this picture, were it visible? (One poster already said a little below the center of the dark disk of Sat...

On average: 1) I have cloud filled skies whenever an astronomical event occurs. 2) I spend a lot of time with my head below the clouds. Hear, hear. It seems to happen to me a lot, too. I'm hoping ISON will be good and that I won't have party-spoiling weather. ---------- I can understand that the an...

Is it serendipity that we are looking into the cave, or would the image appear pretty-much the same from another direction? That is, if the nebula is about the same thickness all around, or are we lucky that the hole is aimed our way? Would it appear similar if our Sun was on the other side of our ...

Chris Peterson wrote:

geckzilla wrote:Heralded, faint, close
Comet ISON approaches
Numbers confuse us

Oh oh. Now you've challenged Art to come up with a sonnet...

Well, if he hadn't, then you have.
I'm looking forward to what he'll come up with.
Maybe it will be an ISONNET.

Cute. Well, I guess it is a picture of stars.

And somewhere down there, if you knew exactly where to look, you would see the satellite's shadow. By "shadow" do you mean the penumbra or the antumbra, exactly :?: So, we need the radius of the Sun, the distance to the Sun, radius of the satellite and distance to the satellite. But I'm p...

@neufer: Thanks for all of the information you posted! I learned a lot from it.

One tongue-in-cheek question. The video of Johnny Mathis (I think that's who it is ...) So was that a new pronunciation for the plural of "Mare" he's singing about ?

I suppose that there should be more impact craters on the far side of the moon. The number of meteors coming from deeper space should probably be more or less constant, but the Earth should shield the moon preferentially toward the side that faces us. Anyone feel like they could tackle this with som...