Starship Asterisk*

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...

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."?

"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"

Wow! That is an extraordinary achievement! Thanks for showing the pic.
Surely the significance and history of the that central belt and the different hemispheres has been discussed somewhere? A link would be gratefully received!
John

What a sparse explanation to this most involved and involving video! Ok, it starts at "Redshift 12", which is how long ago? And ends at "Redshift 0", but no scale or mete is shown. But several do appear with no explanation; "LogM* which increases, "SFR" in "M....

Ida's shape appears to be a long way from spherical, while Dactyl is very round!
How stable will the latter's orbit be, when the gravity field around Ida must vary around it?
John

So much for the Zwicky, if it didn't notice a Super Nova!

Hooray for the human eye, and Koichi Itagaki!
John

Whoever named this "The Medulla" was sadly lacking in anatomy! While it looks nothing like a medulla, it closely resembles the Glomerulus, the primary filtration apparatus in the mammalian kidney.

John

johnnydeep wrote: ↑Wed Jan 18, 2023 8:23 pm

JohnD wrote: ↑Wed Jan 18, 2023 5:05 pm Spectral lines?

Was that in answer to my second question above?

Yes, Johnny. That's a guess, no doubt Chris could confirm or tell us how.
John

Spectral lines?

Gosh! That is most impressive, not just of the Webb's capability, but of the astronomers' (Larson, Hsiao? There's no credit for the pic) dedication in searching the image. To my eye there are signs of lensing, especially on the left with 'smeared' galaxies, but to search for and find THREE images of...

Aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaargh! Not more of this falsely nominative Full Moon stuff! Might as well name them 'Haircut Moon', 'Pancake Moon' (February) or 'Mother in Law Moon' (That's when she visits). These names have nothing to do with the seas...

AH! So rotate the left pic

Ann,
You give us two pics of the Pleiades, one with "suppressed stars", but there seems to be no congruence in the nebulae either. They could be pics of two different objects. What am I missing?

John

No.1 Grandson used his Xmas present from last year, a 'NASA' telescope (about 50mm) to look at the recent full moon, and got very excited.

Would this comet be too ambitious a target for an 8 year old?

Luke Jerram is an English installation artist - his works have included the Museum of the Moon: Museum of the Moon Priory.jpg And Gaia, Gaia Earth Priory.jpg Both have been seen around the world, including at the Lancaster Priory. Huis latest work, Mars, is on tour. Mars Luke Jerram.jpeg What a good...

Quote, Ann: "Of course the size difference is a consequence of the Moon's great proximity to the Earth."

Gosh, Ann, you make it so much clearer than with Ted and Dougal!
https://www.youtube.com/watch?v=MMiKyfd6hA0

And all captained by Shaun the Sheep! But of course, Shaun, for all his uniform and zero-gravity training, cannot pilot the sheep - sorry, ship. Which brings to mind the original design of the Mercury capsules, that had no windows and nothing for the 'pilot' to do, being wholly ground controlled. Fa...

Go, Shaun!

Please, APOD, Artemis 1 is NOT uncrewed! On board is one of ESA's fully trained and experienced astronauts, Shaun the Sheep! Here he is undergoing zero-g training, and with some of the launch team: Shaun zero-g.jpg Shaun launch team.jpg His trainers and Aardman are very proud of Shaun's achievement!...

Yes, a stunning picture, but more highly processed than McDonald's cheese! As the blurb describes, the sky and mountain had to be imaged separately and combined to justify the spurious title, as it shows something a human eye could never see. Observations that our eyes cannot see are commonplace, bu...

10% light speed? Wow! A quick Google finds that to be 67 MILLION mph. They are ionised gas, in the upper atmosphere, so not very dense. Can anyone estimate their mass? Because to accelerate from zero to that, even for a millisecond, must use a heck of a lot of energy, even for a packet of thin gas!...

10% light speed? Wow! A quick Google finds that to be 67 MILLION mph. They are ionised gas, in the upper atmosphere, so not very dense. Can anyone estimate their mass? Because to accelerate from zero to that, even for a millisecond, must use a heck of a lot of energy, even for a packet of thin gas! ...

"Curiosity continues to explore Gale crater on Mars, looking for clues of ancient life. Simultaneously, 2300 kilometers away, its sister rover Perseverance explores Jezero crater"
Surely "daughter" rover? Perseverance is another generation, even if it has the family look!
John

Again, have I discovered, and am suffering from, an acquirable form of colour blindness? Quote blurb, " The featured picture combines visible light from the Hubble Space Telescope in purple, X-ray light from the Chandra X-ray Observatory in blue, and infrared light from the Spitzer Space Telesc...