Starship Asterisk*

What creates the illusion that the Moon has rings is the fact that the long narrow cloud bank that passes in front of it consists of two parts: one dense and dark, which seems to cut the face of the Moon in half, and one much thinner, which seems to disappear as it passes in front of the luminous f...

As Enceladus is spewing out water containing organics, shouldn't those surface features be a sort of mucky brown colour?

The second law of thermodynamics says that the entropy of a system is always increasing, and so eventually everything will be in a state of max disorder and "evenly mixed", but looking scenes like the Triffid Nebula (estimated age 300,000 years) it's difficult to imagine that the universe...

The second law of thermodynamics says that the entropy of a system is always increasing, and so eventually everything will be in a state of max disorder and "evenly mixed", but looking scenes like the Triffid Nebula (estimated age 300,000 years) it's difficult to imagine that the universe ...

Ann wrote: ↑Thu Aug 08, 2024 6:03 am You can tell the picture is old because of the lovely colors.

The random hairs caught on the negative are also a giveaway - but maybe less intrusive than satellite trails!

Living on the benign surface of this earth it is difficult to imaging the enormous forces that exist under our feet, and to an even greater extent, the mind bending forces that come into play between the stars and dust of our galaxy. This short video does something to bring them both into focus. As ...

I assume the stars were digitally removed in this image? When we look at the image at full resolution, there are lots of small faint little disks. Alex Yes - A direct comparison with the almost equivalent image from wikpedia Todays image https://apod.nasa.gov/apod/image/2406/AraDragons_Taylor_4728....

a Wolf-Rayet nebula is primarily shaped by the tremendous heat and wind of its own central star Ann I have trouble getting my head wrapped round the way that things work on these scales. If the nebula has something like a 40 light year radius, does that mean that the glow from the nebula has actual...

Is it just me, or is the main APOD link (https://apod.nasa.gov/apod/astropix.html) not working today? It's not just you. Todays APOD is completely blank - really is "open space" :ssmile: Well, it's not so blank now! :D OK. Slow internet (rural Devon) or software update - who knows? But it...

Rauf wrote: ↑Tue May 28, 2024 7:18 am Is it just me, or is the main APOD link (https://apod.nasa.gov/apod/astropix.html) not working today?

It's not just you. Todays APOD is completely blank - really is "open space"

Blue star light does not make purple reflection nebulas! 🤬 Ann The info on the ESA site says The blue, green, red channels capture the Universe seen by Euclid around the wavelength 0.7, 1.1, and 1.7 micron respectively. This gives Euclid a distinctive colour palette: hot stars have a white-blue hue...

So is that little "stem" between 7:00 and 8:00 on the image a jet of some sort? That's the only explanation I can think of. Ann I'm not so sure - on the APOD full sized image, it looks to me as though that "stem" is actually a continuation of one of the limbs of glowing bubbles ...

Some globular clusters have central black holes. I think there are at least two differences. A globular cluster has a different radial density gradient than a galaxy. And a globular cluster has a very different HR diagram than a galaxy, indicating a different formation process. https://upload.wikim...

The typical cruising height of a jet is about 12km and the diameter of the earth is 12,000km so even if the sun is setting on the horizon a shadow would only be cast effectively horizontally (maybe upward at 1 or 2 degrees). But great picture!

why did the swirling clouds freeze in place-was this faked? please answer The clouds on Jupiter are not static. They are moving at speeds of hundreds of miles per hour. But Jupiter is so big (diameter 88,695 miles or 142,800 km) that the clouds don't appear to move significantly during this fly-by ...

Couldn't understand one basic aspect. Why the eclipse is seen starting from west coast in US to east coast in US.. Apparent motion of moon from east to waste should be faster than Sun's apparent motion from east to west.. So I was imagining it'd start from east coast and move towards west coast. An...

Does this mean that the release of gas from the parent body of Pons-Brooks is "episodic"? Like a series of little explosions? Ann It probably depends on the exact chemical composition, the physical structure of the material and how long each surface is in the full glare of the sun as the ...

they are both affected by the hostile environment of the galaxy cluster, so they are transiting away from their spiral shape and gradually shutting down their star formation. Ann Why is the galaxy cluster such a hostile environment for star formation? I would have thought that all the chaotic movem...

Also take a look at an amazing picture of the 300,000 light-year-long tidal tail of NGC 3628! :shock: https://asterisk.apod.com/download/file.php?id=49354&mode=view Tidal tail of NGC 3628. Credit: Mark Hanson. Thanks for highlighting this Ann. It took me a while to realise that the tidal tail o...

Sorry, you have two wrong explanations here. It was NOT the SpaceX Falcon9 rocket from Cape Canaveral. It couldn't be , since that one launched AFTER this spiral event already had occured , and that one did not fly on an orbit far north enough to reach the high arctic skies.... The fact is , it was...

I have only experienced a total solar eclipse under a cloudy sky on a hill top in Dartmoor but it something that I will never forget. If you get the chance this year, than take it. Was it the solar eclipse of August 11, 1999? Yes! That was it. I had cycled for 2 days from Poole in Dorset to get ove...

I have only experienced a total solar eclipse under a cloudy sky on a hill top in Dartmoor but it something that I will never forget. If you get the chance this year, than take it.

some sources say that silver is created in the earth's mantle from sulphur by the intense heat and pressure. That's incorrect. Transmutation of elements requires conditions like those in the core of a star, which are far more severe than those inside any planet. Quoting the Wikipedia article https:...

I was going to add the other astronomical reference for this APOD - that the sliver in this coin was created in supernova explosions billions of years ago, but some sources say that silver is created in the earth's mantle from sulphur by the intense heat and pressure. Can anyone shed light on which ...

That's a spectacular collection of peculiar galaxies @Ann. Or should that be a peculiar collection of spectacular galaxies? Don't forget the spectacular collection of spectacular galaxies, and the peculiar collection of peculiar galaxies. Honestly, I'd like to see both of those collections as well!...