Starship Asterisk*

At the end of one of the legs of the dancing figure upper left of center is an encircled star. I know too little to hazard a guess. Is this some form of planetary nebula? That would be V1331 Cyg, see: http://www.spacetelescope.org/images/potw1509a/ With its helical appearance resembling a snail’s s...

Why is the Sun different sizes? Sep 30 being the smallest. The relatively small disc on September 30th in the picture looks like it's due to considerably less exposure, and therefore shows less distortion than most of the other solar images, which look enlarged due to flaring from overexposure. The...

... Conversely, today the Sun sets at the North Pole after half a year of continuous daylight." it will set only on september 25, two days from now - all due to the lifting of the sun through the atmosphere and the apparent size of the sun. And don't forget, sunrise and sunset are defined as t...

I think the blue star is Gamma Muscae, mag 3.8. According to Stellarium, it appears combined with two other mag ~7 stars, unresolved at this scale. The separations are all less than 2 arcmin, but I don't know if they are gravitationally related. The bright bluish star is indeed Gamma Muscae, but th...

The "Discuss" link on today's APOD points to yesterday's discussion. I had to type "http://asterisk.apod.com/discuss_apod.php?date=150904" manually to get here From yesterday's discussion page, you could also just click the "Next APOD >>" hotlink under the descriptive ...

Is the apparent curvature of the airglow bands the result of perspective, similar to the effect seen with crepuscular rays? Perhaps emphasized by a very wide-angle lens (judging from the rather small Summer Triangle where the Milky Way meets the horizon)?

Looking at the photographer's site it appears this image may have been taken from Ohio. From the northern hemisphere doesn't it appear like this? http://asterisk.apod.com/download/file.php?id=19528&t=1 Indeed, with a direct view (binoculars) from mid-northern latitudes, the Coat Hanger does loo...

"... this bright stellar grouping is wider than the full moon..." The span of the picture is therefore about one degree. It would be nice if an indication of the span could come with every image. Actually, the long dimension of the "stick figure" seen on the overlay is very near...

If I was dictator of astronomy, it would be called "The Flag Waver". I don't see "The Dumbbell" in this view, at all. Because the name is a reflection of its visual appearance. At an eyepiece, you only see what is red in this image (and you see it as gray). It's those two lobes ...

I would be grateful if someone could please inform me what the "2015 Aug 11.544" means on the image? I'm guessing that the .544 means 54.4% of the way through August 11 2015 and thus shortly after 12:30 p.m., but if so that would be daylight unless the decimal time is equivalent to such a...

Am I seeing things? On my computer screen the photograph is 10" from left to right and Andromeda, although faint, appears to be 1.5" of the 10" total. The center of the galaxy is easy and bright, but is that 1.5" disk the actual size on Andromeda in our sky if we could see it mo...

If you're wondering about the identity of the background sky, here's a copy with some labels.

That said, I'd be cautious about relating the size of something seen in an image to something you've seen with your eyes. In many images (including this one) there is little to provide any scale. This could be a very small halo imaged with a long focal length lens, or a very large one imaged with a...

Why are there no stars visible ? Today's APOD is obviously well exposed for a sunlit scene. Here on earth, which is essentially the same distance from the light source (the sun), the old rule-of-thumb from back in the days of film was that a sunlit scene with distinct shadows would be properly expo...

Yale News wrote: In the 1990s, a famous Hubble photo dubbed “Pillars of Creation” showed columns of dust and gas in the Eagle Nebula that were in the process of forging new stars. The dust filaments Kenney identified are similar in some ways to the “Pillars of Creation,” except they are 1,000 times...

By the way, readers; immediately after my post, above, I looked at the Earth Science Picture of the Day, and it is the best one I have EVER seen: http://epod.usra.edu/blog/ The picture at that link changes every day, and for 01-August-2015, it's a flame behind a waterfall, whereas the picture for y...

I still say the picture is flipped horizontal as Saturn should be west of Antares, not east! Remember that this picture was taken from the Southern Hemisphere, so it's really the observer that's flipped if you're thinking of the view from the Northern Hemisphere. It was taken on a winter evening lo...

As Chris said, the limitation is the eye. With the naked eye under dark skies you can see a small fuzzy spot where the brightest central core is. But the actual angular size is about 6 full moons wide. That's the angular size of the actual galaxy, and as revealed by images. But not visually. To the...

Another question: the description today suggested that nearest acquisition of Pluto would be 9pm the 24th EST. As I understand UT1, the east coast of the U.S. is five hours negative of UT1 making acquisition occur at 8pm. I'd like to be lurking NASA at the correct hour. Is my timing off or is there...

In that photograph Saturn is visible as well, the brightest light a little to the right and up from Antares...am I right? Yes, you are right. Saturn is near the head of Scorpius and not far from the upper-right edge of the cave entrance. Based on Saturn's position relative to the stars, the picture...

It has to be mentioned that the picture shown is not possible, or is it? Because Venus is blended from the sun above, but if so, there would be day not night! So i think the photographer mirrored the image. Am i right? The image has been rotated 90 degrees counter-clockwise, probably to make a hori...

I ... wanted to share this pic directly with some friends who are coming along, although I have sent them this APOD link:-) I don't know which link you sent, but if you sent them this one (for the APOD home page), the picture will change every day: http://apod.nasa.gov/apod/astropix.html Here's a p...

Hi, Mi name is Fernando Rey and i´m the author of this photograph. The image was shot exactly on June 20th 2015 at 23:20:46h... Fernando, I was wondering, what time zone is the reported 23:20:46 on June 20th? CET (Central European Time, UT+1) or CEST (Central European Summer Time, UT+2)? Looking at...

Based primarily on the position of the moon, this picture was taken on August 28, 2014. The moon was about 3.7 days old and 12% illuminated (i.e., a moderately thin crescent as shown in the mouseover inset). Some of the labeled astronomical features are... Humu = Altair Nai'a = Delphinus Ka Maka = S...

... The total phase of the April 4, 2015 lunar eclipse lasted less than 5 minutes, the shortest total lunar eclipse of the century . Barely total or barely partial, we may never know. Sky & Telescope has an online article about the questionable totality... http://www.skyandtelescope.com/astrono...