Search found 1568 matches
- Tue Aug 17, 2021 1:29 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: M57: The Ring Nebula from Hubble (2021 Aug 17)
- Replies: 16
- Views: 4194
Re: APOD: M57: The Ring Nebula from Hubble (2021 Aug 17)
Chris, OK, I imagined a simple explanation, and was wrong, but I can do complexity! You will be as short of time as any busy academic - please refer me to some source that will explain the mechanism? Neufer, Thank you! So the blue is due to Oxygen, not Helium? But why is that fluorescing near the st...
- Tue Aug 17, 2021 9:53 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: M57: The Ring Nebula from Hubble (2021 Aug 17)
- Replies: 16
- Views: 4194
Re: APOD: M57: The Ring Nebula from Hubble (2021 Aug 17)
The intense spectrum of colours across the Ring Nebula represent the different elements being ionised and then fluorescing at a distinct frequnency and colour. So the spectrum represents a gradient of elements in the nebula that depends on their distance from the star. How does this gradient form? I...
- Mon Aug 02, 2021 1:23 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Pluto in Enhanced Color (2021 Aug 01)
- Replies: 15
- Views: 4924
Re: APOD: Pluto in Enhanced Color (2021 Aug 01)
Good point, neufer! Nicely made! And lava tubes are a feature of both Earthly and Lunar geology. So, perhaps a coating of ice over a flowing river of water? BUT! Look at the shape of the Virgil Fossa as it approaches Elliot (click on my pic above for an enlarged version) The Fossae are jagged rifts,...
- Mon Aug 02, 2021 11:03 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Pluto in Enhanced Color (2021 Aug 01)
- Replies: 15
- Views: 4924
Re: APOD: Pluto in Enhanced Color (2021 Aug 01)
Thank you, neufer, and Ann for the tutorial on cryovolcanism! But I repeat - there is no possibilty of liquid water on the surface of Pluto, or of amonia in liquid form, or methane either, when the appearance of the Virgil Fossae as it approaches Elliot resembles an eroded water channel. Ice II or I...
- Mon Aug 02, 2021 10:19 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Hubble Ultra Deep Field in Light... (2021 Aug 02)
- Replies: 40
- Views: 21510
Re: APOD: The Hubble Ultra Deep Field in Light... (2021 Aug 02)
Is this for blind astronomers? I have no doubt there are some, and good luck to them! Rather than how far, 'What'? What is the object almost in the centre of the field, that looks like a diagonal bar of light? There is a single bar just above it, and several others elsewhere in diofferent orientatio...
- Sun Aug 01, 2021 9:46 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Pluto in Enhanced Color (2021 Aug 01)
- Replies: 15
- Views: 4924
Re: APOD: Pluto in Enhanced Color (2021 Aug 01)
Ann makes a case for the Sputnik Platina having been liquid at some time. Does this ignore the abilty of some 'solid' substances to flow over long periods of time? Such as shown by the U of Queensland's Pitch Drop experiment? 800px-University_of_Queensland_Pitch_drop_experiment-white_bg.jpg And, I n...
- Sun Aug 01, 2021 9:12 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Mars 2020 from 5,000 Feet (2020 Jul 31)
- Replies: 17
- Views: 8843
Re: APOD: Mars 2020 from 5,000 Feet (2020 Jul 31)
Oops? The "discuss" link from the APOD of 7/31/2021 - https://apod.nasa.gov/apod/ap210731.html - links to this old APOD discussion. How does an aerial photo of a rocket launch "link" to a ground based picture of the Great Bear and Comet NEOwise? Apart from the hyperlink that joh...
- Fri Jul 30, 2021 10:27 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Ring Galaxy AM 0644-741 (2021 Jul 28)
- Replies: 26
- Views: 6899
Re: APOD: Ring Galaxy AM 0644-741 (2021 Jul 28)
If you zoom in on the eliptical galaxy left mid. you see something that actual looks like a black hole as it would be in visible light passing in front of it low right. I can't upload pictures otherwise I could show it. It's not. Black holes can't be optically resolved. They're far too small. Not t...
- Wed Jul 28, 2021 8:33 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Ring Galaxy AM 0644-741 (2021 Jul 28)
- Replies: 26
- Views: 6899
Re: APOD: Ring Galaxy AM 0644-741 (2021 Jul 28)
Like the famous picture of Hoag's Object https://apod.nasa.gov/apod/ap100822.html in which another ring galaxy appears in the background, this picture does the same. Ann's Object No.4 (bottom left) appears to be very similar to AM 0644-741!
JOhn
JOhn
- Mon Jul 19, 2021 11:53 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Alphonsus and Arzachel (2021 Jul 17)
- Replies: 23
- Views: 8775
Re: APOD: Alphonsus and Arzachel (2021 Jul 17)
Just to check, a quick shot by mobile of the half moon in my sky.
JOhn
And it works! I promise not to abuse!
- Mon Jul 19, 2021 10:54 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Alphonsus and Arzachel (2021 Jul 17)
- Replies: 23
- Views: 8775
Re: APOD: Alphonsus and Arzachel (2021 Jul 17)
XgeoX, I'm looking at the 'Full Editor' now. It has an "Insert Image" button which generates pairs of square backets, with 'img' and '/img' in them. But pasting anything into the space in the middle gets nothing. There's something in the FAQ about posting images that are online, not on one...
- Mon Jul 19, 2021 10:15 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Alphonsus and Arzachel (2021 Jul 17)
- Replies: 23
- Views: 8775
Re: APOD: Alphonsus and Arzachel (2021 Jul 17)
Several members above have posted images. I see from the FAQ page that image posting is allowed if so enabled for that thread (which clearly has been done) and if that member has the priviledge. May I post images, please?
JOhn
JOhn
- Sat Jul 17, 2021 1:47 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Alphonsus and Arzachel (2021 Jul 17)
- Replies: 23
- Views: 8775
Re: APOD: Alphonsus and Arzachel (2021 Jul 17)
And to prove that great minds think alike, see:
https://epod.usra.edu/blog/2019/07/the- ... moon-.html
https://epod.usra.edu/blog/2019/07/the- ... moon-.html
- Sat Jul 17, 2021 1:23 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Alphonsus and Arzachel (2021 Jul 17)
- Replies: 23
- Views: 8775
- Sat Jul 17, 2021 10:28 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Alphonsus and Arzachel (2021 Jul 17)
- Replies: 23
- Views: 8775
Re: APOD: Alphonsus and Arzachel (2021 Jul 17)
Both of those are "Rille", a German word for 'groove' that seems to be given a Latin name in the plural, "Rimae", for some reason. They may be straight or more usually 'sinuous'. There are many rimae on the Moon and other bodies of the Solar System, and many explanations for them...
- Fri Jul 16, 2021 9:29 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Saturn's Iapetus: Painted Moon in 3D (2021 Jul 13)
- Replies: 25
- Views: 6323
Re: APOD: Saturn's Iapetus: Painted Moon in 3D (2021 Jul 13)
A very good point, Chief Dan! Looking again at the APoD, the dark part is dark, all over. The white part has many black spots, as if from incomplete coverage or later erosion of a white covering. That giant crater near one pole (of the image, possibly not the real pole) has the rim on the side neare...
- Wed Jul 14, 2021 10:27 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Saturn's Iapetus: Painted Moon in 3D (2021 Jul 13)
- Replies: 25
- Views: 6323
Re: APOD: Saturn's Iapetus: Painted Moon in 3D (2021 Jul 13)
John Milton knew a thing or two about dark material Into this wild abyss, The womb of Nature and perhaps her grave, Of neither sea, nor shore, nor air, nor fire, But all these in their pregnant causes mixed Confusedly, and which thus must ever fight, Unless the almighty Maker them ordain His dark ma...
- Tue Jul 13, 2021 6:28 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Saturn's Iapetus: Painted Moon in 3D (2021 Jul 13)
- Replies: 25
- Views: 6323
Re: APOD: Saturn's Iapetus: Painted Moon in 3D (2021 Jul 13)
Thnak you Art! "Within the bright regions there is no ridge, but there are a series of isolated 10 km peaks along the equator. "
Now I see it! Within the dark area.
John
Now I see it! Within the dark area.
John
- Tue Jul 13, 2021 8:22 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Saturn's Iapetus: Painted Moon in 3D (2021 Jul 13)
- Replies: 25
- Views: 6323
Re: APOD: Saturn's Iapetus: Painted Moon in 3D (2021 Jul 13)
Indeed, a fascination toy, to roll and bauble with! But I'm missing the "equatorial ridge". If I can see it then the axis that the image spins on passes through it, so it should be called the transpolar ridge, but this may be a product of the passage of Cassini past the moon, rather than i...
- Sun Jul 11, 2021 11:11 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Find the Moon (2021 Jul 11)
- Replies: 9
- Views: 3059
Re: APOD: Find the Moon (2021 Jul 11)
https://vecta.io/symbols/198/symbols-geometric/32/black-large-square If you look VERY carefully, you can see a cat in the picture above. The cat is black, it was taken in a coal celler at midnight and the photographer's flash gun failed. Just thought you would like to know the technical details of t...
- Thu Jul 08, 2021 9:41 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Perihelion to Aphelion (2021 Jul 08)
- Replies: 15
- Views: 3390
Re: APOD: Perihelion to Aphelion (2021 Jul 08)
So January 4th, the next perihelion we will have a SUPERSUN! 'Cos it will be 3% bigger!!!!
Break out the whoowhoo flags, invent new names for these aspects, just like all the flimflam about the Moon that is so boring.
Nice pics!
Break out the whoowhoo flags, invent new names for these aspects, just like all the flimflam about the Moon that is so boring.
Nice pics!
- Fri Jun 25, 2021 3:14 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: 2014 UN271
- Replies: 20
- Views: 7645
Re: 2014 UN271
Thank you, Chris!
- Fri Jun 25, 2021 12:10 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Andromeda in a Single Shot (2021 Jun 25)
- Replies: 16
- Views: 5277
Re: APOD: Andromeda in a Single Shot (2021 Jun 25)
What do you mean, EM? That Andromeda should have been bigger in the sky? That would have screwed up the Milky Way, which it will do, one day in the future, as we rush towards it! It's the only galaxy that's naked eye visible, and was known when the Ptolomeic model of the Universe reigned, but as a '...
- Fri Jun 25, 2021 10:46 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Andromeda in a Single Shot (2021 Jun 25)
- Replies: 16
- Views: 5277
Re: APOD: Andromeda in a Single Shot (2021 Jun 25)
Set the ccontrols for the heart of the Sun/Galaxy! Fire when she bears, Mr.Mate!
- Fri Jun 25, 2021 8:57 am
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: 2014 UN271
- Replies: 20
- Views: 7645
Re: 2014 UN271
You don't think this minor planet sized comet is of that much interest, Chris? Other missions have been launched (OsirisREX, Hayabusa) to bring back specimens of primordial material. Something from the Oort Cloud is as primordial as they come! A specimen return mission would seem beyond possibility ...