Starship Asterisk*

I note also the very small galaxy just below in today's image. I assume that it too is a companion. Note the bright, small center of it. Assuming that all galaxies have black holes at their cores, including this very small galaxy, what conclusions can we draw for the prevalence of black holes (small...

I had read in advance of the eclipse that if it was my first (it was) then I shouldn't bother trying to photograph it, but rather just enjoy it. The idea is that there will be people with better equipment and more experience than I and they will be sharing their pictures over the internet. Boy, was ...

I would like to know where we are on this amazing" map", an arrow saying "you are here". I am serious. If I understand the mapping, the center of the galaxy is in the center, the galactic poles, north and south, are at the top and bottom, respectively and half way around, either...

I am just staggered that they can get a spectrum from such a tiny dot of light in a field full of sources of light AND with undoubtedly such a miniscule AMOUNT of light! Does Hubble have variable sized masks to allow only the selected source of light through to a spectroscope? Astronomy sure has adv...

I have two comments: 1) Hit replay over and over again so as to see details you missed the first (or tenth) time. Note the initial, very high speed spray that fans out to the left and disappears. That spray is moving much faster than the others. 2) Note the surface of the sun as the cooler plasma ra...

"... ikely due to massive black holes near the galaxy's center."

Is there a reason to suspect that there is more than one massive black hole at the center?

Let me say that one can make an estimate of the angle of the sun as viewed from the ground, not up three stories high, as I had estimated in my previous post that I thought the camera might have been. There is a clue in the center of the picture: a pedestrian dangerously in the crosswalk against the...

If you have ever done celestial navigation aboard a boat at sea, you will remember that you have to estimate the height of the sextant above the water at the time of the shot. After all, the higher you are, the farther over the horizon you can see. Draw some exaggerated drawings of a globe and a sai...

It seems to me that if you compress all those planets inside the orbit of one AU, then the big ones (the ones the size of Jupiter and Saturn) would fling out of their orbits the other smaller ones. Since they are all in (relative) close proximity, it doesn't seem as though stable orbits for so many ...

The "Saros Numbers" hyperlink seems incorrect and does not take one to another webpage ? I was just going to say this. It appears the date is missing a digit. It's very cool that one individual was able to travel to each of those places to capture these images! 8-) The hyperlink appears t...

Probably nobody is even watching the Discussion page on this APOD of 2016 06 15 anymore, but I couldn't help myself. With two detected in three months, one has to be simultaneously interested that they are so often (from an observer's point of view) and yet so rare (as the volume of space inside a r...

The previous posters needed to learn patience. I, for one, am very excited at the news of a second detection of gravity waves. I know that landing a human on the moon a second time is less exciting than the first but in the field of science, confirmation by repetition is crucial. I, for one, I'm ver...

Oops. ".. our computer monitors .." not ".. out computer monitors"

I am curious about the color mapping. UV, X-ray and Gamma-ray frequencies are not visible to the human eye (and hopefully not capable of being reproduced by out computer monitors), so to make the image visible, there has to have been a color mapping. How many frequencies were imaged, what frequencie...

I suspect that these wonderful colors we see in the resultant photo were wholly invisible to the photographer's naked eye. They were probably too faint to register except upon the time exposure. Thus, the photographer might have just been surprised when he first saw his own photo.

I haven't been this excited by news coming from the astronomical community for a very very long time. This is really big news! Congratulations to all the team at LIGO! Now that we have data of an event superimposed over the noise (see the signals at the far left of the image) perhaps we can start to...

A picture such as this would be ideal to have a "rollover" second picture (displayed when the mouse cursor is on it) with the focus on the stars and the pine out of focus.

I would love to see the astronomers' preliminary analysis of supposed light paths through the complicated gravitational lenses. It undoubtedly is quite complicated, considering how lumpy the matter is. I would have expected the image to arrive first to be the center of the three, then the later ones...

I wonder. Would the Zodiacal light appear brighter or dimmer when viewed in the asteroid belt. Do we have any pictures by the Dawn spacecraft orbiting Ceres (or before when it orbited Vesta) where the Sun is just below the horizon? Would it be dimmer because it is farther from the source? Might it b...

I am really sorry that I am joining this thread so late that I might not get any responses to my question. Let us suppose the upper track is close to half way between apogee and perigee, so that the rate of change of altitude is maximized. Next let us suppose that the orientation of the apogee and p...

In other words, how much mass is floating around in our galaxy dark and invisible, but for minor (very minor) gravitational lensing? Probably none. Because such matter still has an electromagnetic signature- in the IR typically, but depending on conditions it could be in the UV or radio spectrum, a...

In the hyperlink to LDN 1495, it talks of the NH3 being gravitationally bound (some of it) and some of it being pressure bound and that each of those can collapse into protostars. I wonder how much of such material collapse into "solar systems" but with an inadequately massive center objec...