Starship Asterisk*

« Gravitational tidal forces are dragging it down. » That assertion is puzzling, at best : isnt'it well known from the observation and analysis of our own Earth-Moon binary system that the effect of tidal forces is to cause mechanical stress and deformation in the bodies which disispate energy in t...

Mu Cephei looks like a glowing ember to me mdash bright orange. Of course, my black body tool would be useless on that star. Not necessarily so; I had misremembered mu Cep's spectral class when I wrote this. As it turns out, a published surface temperature of mu Cep yields a black body color simila...

Oh, he's a hockey player! No wonder I had no freakin' idea what Pucknut was talking about. Mark Messier now becomes the 4th hockey player whose name I have ever learned. Ever. And there's no guarantee that I'll remember his first name tomorrow. 4 ?? You're one ahead of me. Besides Mark, i only reme...

What's this Messier 17 nonsense? Everyone knows Messier wore No. 11 when he played for the Oilers, Rangers and Canucks! Duh. What? This isn't about Mark Messier? On Tuesday, February 27th, Mark Messier's #11 banner will rise to the top of Rexall Place, to take its place alongside a number of other ...

The names given this object (Swan, Omega) are based on its visual appearance through a telescope eyepiece, which is nothing like what we get with a deep color image. I have never been able to see an omega through the eyepiece. I could never figure out why it was called the Omega Nebula until I saw ...

Disputing whether or not M104 is part of the Virgo Cluster is like disputing whether or not Pluto is a planet. I've seen estimates of the distance to M104 vary from 25 Mly to 50 Mly. If it's only 25 Mly, then it is unambiguously not part of the cluster. But at 50 Mly, according to my math, it would...

So, is it now established that M104 is part of the Virgo Cluster, or is that still disputed?

They would most likely all have different specific answers, not knowing quite what perigee is or how to be concise in their wording, but the core meaning of their answers would probably be pretty similar. It means a bigger moon. I've got a few non-astro friends hanging around on Facebook and the su...

Why is the Moon darker than the glow surrounding it?

What is the experts' take on this state, after watching the phenomenon ? I found the "super" moon was rather dull during totality, but hey! my sight is not good and obviously I haven't seen hundreds of "super red moons" in my life lapse so far. It was one of the darker total lun...

For some reason, the full Moon went quite dim last night, so I took advantage of this turn of events to look at Mirach. It appeared a bright orange yellow in the center, a bit more on the orange side than in Mr. Park's photo, with copper-colored fringes. Unfortunately, my telescope was poorly collim...

Mu Cephei looks like a glowing ember to me mdash bright orange. Of course, my black body tool would be useless on that star. I don't have a tool to model the effect of our atmosphere on the color of extraterrestrial objects. I guess I could create one by comparing the extraterrestrial solar spectrum...

If these mergers take place 10+ billion years in the future, the Sun will probably be a fading Planetary Nebula...with us long gone, and Mirach long Exploded,....they don't have a crying emoticon. As Neufer mentioned, the Sun will have long passed its pretty death shroud phase. Also, at 3 to 4 sola...

As a color commentator I find the colors very interesting. The bright yellow color of Mirach is very striking. We are often told that M-type stars are very red, but when I looked at M-type stars through a telescope, I often thought they looked this sort of yellow. To me, M stars have appeared from ...

I just have to say... This is awesome! Good job, Hartwig Luethen.

Elmar wrote:Why is the first track curved?

It isn’t. You’re experiencing what Neil deGrasse Tyson calls a “brain failure,” and the rest of us call an optical illusion.

According to the photographer:

[T]his image is the combination of 45 13 second images without a tracking mount. I manually aligned these images on the star field to put the meteors in their respective location.

A cross-eyed pair. Image credits are embedded.
Edit: Ah, Neufer, you beat me to it!

The problem with direct stereographic images is that my eyes simply refuse to merge images more than about 6 cm wide. I think the people who can do “free” viewing with images this large must have double-jointed eyes.

On the other hand, I never have trouble with cross-eyed images.

So, just how far away is this galaxy? Is it 28 Mly, as HubbleSite.org (STScI) claims? Is it 1/2 the distance to the Virgo Cluster (about 25 – 28 Mly), as NightSkyInfo.com claims? Is it 11.118 Mpc (36 Mly), as NED claims? Or is it 50 Mly, as claimed by SEDS.org , SpaceTelescope.org (ESA), and today’s...

It would have been a better picture if it were oriented correctly. I can't believe I'm reading this in an astronomy forum. This is an astronomy and pedant forum, though. I understand well that there is often a fine line between pedantry and correcting someone who is just plain wrong, but asking for...

Charles Bull wrote:It would have been a better picture if it were oriented correctly.

I can't believe I'm reading this in an astronomy forum.

Not to be TOO picky (is that possible?), but it wasn't the _crescent_ phases of Venus that did the trick. The full and gibbous phases were the problems for Ptolemy's followers. See, for example: http://astro.unl.edu/classaction/animations/renaissance/ptolemaic.html http://www.wpclipart.com/space/di...

I don't think that the moons of Jupiter, on their own, would have caused insuperable difficulty for the Ptolemaic system. The phases of Venus were the clincher. Perhaps not, but they did resolve a philosophical question. The Copernican system had two centers of motion, the Earth (for the Moon) and ...

Am I missing something? Wikipedi-ing around I find that the first telescopes were made in 1608 while Copernicus died in 1543? The description does not say that Copernicus saw this view; it only says that this view supported the Copernican system. Indeed, a link in the description points to an artic...