Search found 1564 matches
- Thu Nov 02, 2023 11:37 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Galaxy Cluster Abell 370 and Beyond (2023 Sep 12)
- Replies: 28
- Views: 15131
Re: APOD: Galaxy Cluster Abell 370 and Beyond (2023 Sep 12)
The main article in this weeks New Scientist is "In Search of Quantum Gravity". See: https://www.sciencedirect.com/science/article/abs/pii/S0262407923020122 if you don't have a subscription to NS. The author is a journalist, not a scientist! She describes the work of Kathryn Zurek, who pro...
- Sun Oct 29, 2023 9:31 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: A Partial Lunar Eclipse (2023 Oct 29)
- Replies: 11
- Views: 14932
Re: APOD: A Partial Lunar Eclipse (2023 Oct 29)
A "Hunter's Moon" is it?
- Sat Oct 28, 2023 4:31 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Ghosts of Gamma Cas (2023 Oct 28)
- Replies: 8
- Views: 15914
Re: APOD: The Ghosts of Gamma Cas (2023 Oct 28)
Thank you, Chris!
The blurb made it sound like some unknown chemistry was just pooouff! making it not exist!
The blurb made it sound like some unknown chemistry was just pooouff! making it not exist!
- Sat Oct 28, 2023 3:26 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Ghosts of Gamma Cas (2023 Oct 28)
- Replies: 8
- Views: 15914
Re: APOD: The Ghosts of Gamma Cas (2023 Oct 28)
The blurb to this APOD described the clouds of gas and dust as, "slowly disappearing, eroding under the influence of energetic radiation from hot and luminous gamma Cas." So where is it going? If the dust is being reduced to gas, why isn't that made luminous? Is the gas being reduced to pr...
- Tue Oct 24, 2023 4:46 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Arp 87: Merging Galaxies from Hubble (2023 Oct 24)
- Replies: 18
- Views: 15783
Re: APOD: Arp 87: Merging Galaxies from Hubble (2023 Oct 24)
Thank you, Ann and Chris!
So, what factor should be added to Drake's Equation, R* x FP x Ne x FL x FI x FC x L = Number of intelligent civs?
And does this answer Fermi's question, "Where is everybody?" ?
John
So, what factor should be added to Drake's Equation, R* x FP x Ne x FL x FI x FC x L = Number of intelligent civs?
And does this answer Fermi's question, "Where is everybody?" ?
John
- Tue Oct 24, 2023 9:12 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Arp 87: Merging Galaxies from Hubble (2023 Oct 24)
- Replies: 18
- Views: 15783
Re: APOD: Arp 87: Merging Galaxies from Hubble (2023 Oct 24)
Great series of pics, Ann! Now, I KNOW that every star in those galaxies is light years from the next, and I KNOW that a process such as this is over a very long period, but what would it be like to live in one of colliding galaxies? "Violent tides", "bursts of star formation" it...
- Sun Oct 22, 2023 11:53 am
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: Special moons
- Replies: 0
- Views: 74926
Special moons
The habit of giving particular instants in the inevitable and unending (in human history or future)m orbit of the Moon around Earth is annoying. To me at least, while my criticism of this practice has inflamed others. So enjoy this, woo-woos!
John
John
- Wed Sep 27, 2023 10:15 am
- Forum: Open Space: Discuss Anything
- Topic: The Earth is bleeding!
- Replies: 3
- Views: 15798
Re: The Earth is bleeding!
Actually Randolph, the Geldingadur eruption has stopped! See: https://www.youtube.com/watch?v=uZGleOgreBY
Sure, Iceland is an extraordinary island that sits on the Mid-Atlantic Ridge, so new eruptions and revivals of dormant sites may be expected, but this one has gone silent. For now!
John
Sure, Iceland is an extraordinary island that sits on the Mid-Atlantic Ridge, so new eruptions and revivals of dormant sites may be expected, but this one has gone silent. For now!
John
- Mon Sep 25, 2023 3:53 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Arp 142: The Hummingbird Galaxy (2023 Sep 25)
- Replies: 38
- Views: 20202
Re: APOD: Arp 142: The Hummingbird Galaxy (2023 Sep 25)
Thank you, Ann!
John
John
- Mon Sep 25, 2023 1:49 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Arp 142: The Hummingbird Galaxy (2023 Sep 25)
- Replies: 38
- Views: 20202
Re: APOD: Arp 142: The Hummingbird Galaxy (2023 Sep 25)
No, Ann! My question must have been unclear may I try again ? The blurb says that ARP 142 was distorted when "it got too close to the massive elliptical galaxy NGC 2937" which I presume is the one in the centre of your left pic - looks the same as in today's APoD. That galaxy appears as a ...
- Mon Sep 25, 2023 9:25 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Arp 142: The Hummingbird Galaxy (2023 Sep 25)
- Replies: 38
- Views: 20202
Re: APOD: Arp 142: The Hummingbird Galaxy (2023 Sep 25)
ARP 142 is "about 300 million LY away" the blurb says. So how close to it is the elliptical, NGC 2937?
I ask, because while the elliptical's stars are just a mist, no individuals discernible, there are many in ARP 142 that appear as single stars. Or do my eyes deceive me?
John
I ask, because while the elliptical's stars are just a mist, no individuals discernible, there are many in ARP 142 that appear as single stars. Or do my eyes deceive me?
John
- Tue Sep 19, 2023 9:50 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: HH 211: Jets from a Forming Star (2023 Sep 19)
- Replies: 16
- Views: 4493
Re: APOD: HH 211: Jets from a Forming Star (2023 Sep 19)
Why are there extra lobes of the jet in the upper-right? Intermittent jetting? If you click on the "hypothesize" link, you can read the abstract about just this. In which I love the use, in a serious astrophysics paper, of the term "wiggle"! And just to orientate us, Ann has exp...
- Tue Sep 12, 2023 9:53 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Galaxy Cluster Abell 370 and Beyond (2023 Sep 12)
- Replies: 28
- Views: 15131
Re: APOD: Galaxy Cluster Abell 370 and Beyond (2023 Sep 12)
JIm, Since we cannot detect Dark Matter in the Solar System let alone 4 billion light years away, that blue cloud must be theoretical , not observation. It's derived from conventional physics theory, and 'photoshopped' in. I read recently that the latest attempts to push definition and detection to ...
- Tue Sep 12, 2023 8:18 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Galaxy Cluster Abell 370 and Beyond (2023 Sep 12)
- Replies: 28
- Views: 15131
Re: APOD: Galaxy Cluster Abell 370 and Beyond (2023 Sep 12)
I can see four stars with diffraction spikes, so are ALL the other objects in that photo beyond the Milky Way?
If so, well, Gosh!
But another question, why do distant object not raise spikes?
Thanks,
John
If so, well, Gosh!
But another question, why do distant object not raise spikes?
Thanks,
John
- Mon Sep 04, 2023 9:06 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Comet Schwassmann-Wachmann 3 Fragments (2023 Sep 03)
- Replies: 28
- Views: 11080
Re: APOD: Comet Schwassmann-Wachmann 3 Fragments (2023 Sep 03)
Thank you, Chris! So there are many effects on the debris from a cometary outburst, that pushed them into an expanding torus along the orbit of the parent object? Which brings me to the other point in my original Q - in the APOD picture, if you draw a line between the Comet and the centre of the bun...
- Sun Sep 03, 2023 10:12 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Comet Schwassmann-Wachmann 3 Fragments (2023 Sep 03)
- Replies: 28
- Views: 11080
Re: APOD: Comet Schwassmann-Wachmann 3 Fragments (2023 Sep 03)
Indeed, emc, only the truly ignorant don't ask questions.
I know that this site will inform me.
John
I know that this site will inform me.
John
- Sun Sep 03, 2023 9:44 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Comet Schwassmann-Wachmann 3 Fragments (2023 Sep 03)
- Replies: 28
- Views: 11080
Re: APOD: Comet Schwassmann-Wachmann 3 Fragments (2023 Sep 03)
Some explanation for the ignorant (me) please? The break-up may be moderately explosive, like a geyser eruption on Earth, but how do the fragments become so separated? Are they scattered along the orbit of the parent comet? Or, as all their tails are aligned, but they are all along the same line, in...
- Thu Aug 31, 2023 10:02 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Crew-7 Nebula (2023 Aug 31)
- Replies: 13
- Views: 3231
Re: APOD: The Crew-7 Nebula (2023 Aug 31)
Which gorilla? Not even Uncle Boris!
Someone from Cousin Orang's family?
Someone from Cousin Orang's family?
- Mon Jul 24, 2023 5:21 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: Moon impact
- Replies: 3
- Views: 14706
Moon impact
This appeared on Facebook.
https://www.facebook.com/reel/276761901549016 An asteroid impacts the Moon.
It has to be a simulation, looks well done, but is of course without explanation or discussion. I'd love to see those from the well-informed people here.
JOhn
https://www.facebook.com/reel/276761901549016 An asteroid impacts the Moon.
It has to be a simulation, looks well done, but is of course without explanation or discussion. I'd love to see those from the well-informed people here.
JOhn
- Sun Jul 23, 2023 2:16 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Antikythera Mechanism (2023 Jul 23)
- Replies: 10
- Views: 2918
Re: APOD: The Antikythera Mechanism (2023 Jul 23)
Anyone seen the new Indiana Jones movie? "Dial of Destiny"? It features Indy searching for the said Dial - which is the Antikythera Mechanism!!! Except in this reality it was recovered from the sea bed "encased in wax", wholly uncorroded and - who knew? - when reunited with its' ...
- Wed Jul 19, 2023 6:36 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Chandrayaan-3 Launches to the Moon (2023 Jul 19)
- Replies: 8
- Views: 2519
Re: APOD: Chandrayaan-3 Launches to the Moon (2023 Jul 19)
The EPoD picture today provides a pleasing coincidence: https://epod.usra.edu/
John
John
- Thu Jun 22, 2023 8:41 am
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: Flat rainbows
- Replies: 1
- Views: 13030
Flat rainbows
A recent EPOD featured a 'flat rainbow', with the usual colours appearing in a plane, over Paris as it happened. But without any explanation. flat rainbow.jpg Googling this I find that they are not unique, are sometimes called 'firebows' and associated with high clouds and water ice crystals rather ...
- Sun Jun 11, 2023 9:00 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Sun and Its Missing Colors (2023 Jun 11)
- Replies: 23
- Views: 8022
Re: APOD: The Sun and Its Missing Colors (2023 Jun 11)
Ann, I understand about absorbtion of colours, but am puzzled. For instance, sodium vapour street lights give off the same wavelength of light that identifies sodium in the Sun. But the sodium in the Sun must be at much higher temperature than in the street light, so why does the solar sodium not gl...
- Fri Jun 09, 2023 11:05 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Pandora's Cluster of Galaxies (2023 Jun 09)
- Replies: 15
- Views: 3955
Re: APOD: Pandora's Cluster of Galaxies (2023 Jun 09)
Since the stars in the constellation are in this galaxy, surely that should be, "three different massive galaxy clusters some 3.5 billion light-years away BEYOND the constellation Sculptor."?
- Sun Jun 04, 2023 9:24 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Color the Universe (2023 Jun 04)
- Replies: 37
- Views: 8978
Re: APOD: Color the Universe (2023 Jun 04)
"There are holes in the sky where the rain gets in,
but the holes are small, that's why rain is thin."
Milligan, S. "Rain"
but the holes are small, that's why rain is thin."
Milligan, S. "Rain"