Search found 40 matches
- Sun Oct 20, 2024 8:44 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Dark Matter in a Simulated Universe (2024 Oct 20)
- Replies: 36
- Views: 7398
Re: APOD: Dark Matter in a Simulated Universe (2024 Oct 20)
https://dlia.org/wp-content/uploads/2019/01/fireflies-DSC_2613.jpg Note that even the real fireflies follow the "filaments" and avoid the "voids"! Now we just have to figure out what makes fireflies imitate that structure of the universe. Ann Could it be that the photographer wa...
- Sun Sep 01, 2024 8:23 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Moon Dressed Like Saturn (2024 Sep 01)
- Replies: 7
- Views: 1975
Re: APOD: The Moon Dressed Like Saturn (2024 Sep 01)
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...
- Sun Aug 25, 2024 8:41 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Fresh Tiger Stripes on Saturn's... (2024 Aug 25)
- Replies: 10
- Views: 2198
Re: APOD: Fresh Tiger Stripes on Saturn's... (2024 Aug 25)
As Enceladus is spewing out water containing organics, shouldn't those surface features be a sort of mucky brown colour?
- Mon Aug 12, 2024 9:00 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Light, Dark, and Dusty Trifid (2024 Aug 10)
- Replies: 22
- Views: 6936
Re: APOD: The Light, Dark, and Dusty Trifid (2024 Aug 10)
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...
- Sat Aug 10, 2024 8:29 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Light, Dark, and Dusty Trifid (2024 Aug 10)
- Replies: 22
- Views: 6936
Re: APOD: The Light, Dark, and Dusty Trifid (2024 Aug 10)
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 ...
- Thu Aug 08, 2024 8:24 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Periodic Comet Swift-Tuttle (2024 Aug 08)
- Replies: 8
- Views: 5338
- Wed Jul 17, 2024 8:52 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Villarrica Volcano Against the Sky (2024 Jul 17)
- Replies: 6
- Views: 5134
Re: APOD: Villarrica Volcano Against the Sky (2024 Jul 17)
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 ...
- Wed Jun 19, 2024 3:50 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: NGC 6188: Dragons of Ara (2024 Jun 19)
- Replies: 8
- Views: 16921
Re: APOD: NGC 6188: Dragons of Ara (2024 Jun 19)
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....
- Fri May 31, 2024 9:03 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Nebulous Realm of WR 134 (2024 May 31)
- Replies: 32
- Views: 9214
Re: APOD: The Nebulous Realm of WR 134 (2024 May 31)
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...
- Tue May 28, 2024 8:03 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Solar X Flare as Famous Active... (2024 May 28)
- Replies: 16
- Views: 5311
Re: APOD: Solar X Flare as Famous Active... (2024 May 28)
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...
- Tue May 28, 2024 7:55 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Solar X Flare as Famous Active... (2024 May 28)
- Replies: 16
- Views: 5311
Re: APOD: Solar X Flare as Famous Active... (2024 May 28)
It's not just you. Todays APOD is completely blank - really is "open space"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?
- Fri May 24, 2024 8:25 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: M78 from the Euclid Space Telescope (2024 May 24)
- Replies: 10
- Views: 4028
Re: APOD: M78 from the Euclid Space Telescope (2024 May 24)
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...
- Wed May 01, 2024 8:27 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: GK Per: Nova and Planetary Nebula (2024 Apr 30)
- Replies: 16
- Views: 3204
Re: APOD: GK Per: Nova and Planetary Nebula (2024 Apr 30)
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 ...
- Sat Apr 27, 2024 9:14 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Regulus and the Dwarf Galaxy (2024 Apr 26)
- Replies: 18
- Views: 3430
Re: APOD: Regulus and the Dwarf Galaxy (2024 Apr 26)
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...
- Tue Apr 23, 2024 8:50 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Contrail Shadow X (2024 Apr 23)
- Replies: 20
- Views: 4181
Re: APOD: Contrail Shadow X (2024 Apr 23)
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!
- Sun Apr 21, 2024 8:34 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Perijove 16: Passing Jupiter (2024 Apr 21)
- Replies: 15
- Views: 2388
Re: APOD: Perijove 16: Passing Jupiter (2024 Apr 21)
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 ...
- Tue Apr 09, 2024 8:31 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Moon's Shadow over Lake Magog (2024 Apr 09)
- Replies: 13
- Views: 2815
Re: APOD: Moon's Shadow over Lake Magog (2024 Apr 09)
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...
- Mon Apr 08, 2024 8:23 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Changing Ion Tail of Comet... (2024 Apr 08)
- Replies: 4
- Views: 1761
Re: APOD: The Changing Ion Tail of Comet... (2024 Apr 08)
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 ...
- Wed Mar 27, 2024 9:21 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Coma Cluster of Galaxies (2024 Mar 27)
- Replies: 13
- Views: 2124
Re: APOD: The Coma Cluster of Galaxies (2024 Mar 27)
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...
- Thu Mar 21, 2024 10:06 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Leo Trio (2024 Mar 21)
- Replies: 23
- Views: 18346
Re: APOD: The Leo Trio (2024 Mar 21)
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...
- Tue Mar 12, 2024 9:38 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: A Galaxy-Shaped Rocket Exhaust Spiral (2024 Mar 12)
- Replies: 6
- Views: 3256
Re: APOD: A Galaxy-Shaped Rocket Exhaust Spiral (2024 Mar 12)
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...
- Tue Mar 05, 2024 9:48 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: A Total Solar Eclipse Close-Up in... (2024 Mar 03)
- Replies: 19
- Views: 4488
Re: APOD: A Total Solar Eclipse Close-Up in... (2024 Mar 03)
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...
- Mon Mar 04, 2024 9:18 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: A Total Solar Eclipse Close-Up in... (2024 Mar 03)
- Replies: 19
- Views: 4488
Re: APOD: A Total Solar Eclipse Close-Up in... (2024 Mar 03)
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.
- Fri Mar 01, 2024 8:03 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Julius Caesar and Leap Days (2024 Feb 29)
- Replies: 24
- Views: 27662
Re: APOD: Julius Caesar and Leap Days (2024 Feb 29)
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:...
- Thu Feb 29, 2024 9:31 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Julius Caesar and Leap Days (2024 Feb 29)
- Replies: 24
- Views: 27662
Re: APOD: Julius Caesar and Leap Days (2024 Feb 29)
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 ...