Starship Asterisk*

Explanation: Braided and serpentine filaments of glowing gas suggest this nebula's popular name, The Medusa Nebula. Also known as Abell 21, ... Abell 21 (AGC 21) is a galaxy cluster. For the Medusa Nebula it's better to use the exact name PN A66 21. https://hla.stsci.edu/cgi-bin/display?config=ops&...

Let's have a look at some details: .. I think that the Bubble Nebula can be compared to the Rosette Nebula, because the Rosette Nebula is a sort of Bubble Nebula too. Of course, the ionizing cluster NGC 2244 (which, if I remember correctly, contains at least three O-type stars) is more energetic th...

Congratulations, what a great composite image! What is unclear to me, is how a single star can create such a bubble shape? ...I especially like the "little ghost nebula" on the bottom right ...;-) https://live.staticflickr.com/65535/51956272439_fd9a6eb98e_w.jpg https://live.staticflickr.co...

I'm a bit surprised that the quality isn't better than Hubble when comparing the resolution of details to the nearest Hubble object. The third image in the series shows the nearby Cat's Eye Nebula overlaid at the same size. But of course, the process of optimizing the instruments is not yet complet...

I'm a bit surprised that the quality isn't better than Hubble when comparing the resolution of details to the nearest Hubble object. The third image in the series shows the nearby Cat's Eye Nebula overlaid at the same size. But of course, the process of optimizing the instruments is not yet complete...

But the galaxies scattered across the background of the Webb telescope alignment evaluation image are likely billions of light-years distant, far beyond the Milky Way. Well done WEBB! I think the WEBB Galaxy Zoo looks really pretty ;-) https://live.staticflickr.com/65535/51946363197_b534c66556_w.jp...

IC447_446GiorgioFerrari1024.jpg Notice that the dark filament also connects to two more objects at the top right of photo! :shock: I think you are right. (The picture is a superposition of different wavelengths in the IR (Herschel(white), GLIMPSE(pink)). https://live.staticflickr.com/65535/51946616...

What is the reason why IC 447 does not also glow in red like Mon 15? There are enough young, hot stars ... 15 Mon is a star, not a nebula. I don't know if the red nebulosity around the Cone Nebula and bright star 15 Mon has a name. All right, at least a part of it is called Sharpless 2-273, and oth...

What is the reason why IC 447 does not also glow in red like Mon 15?
There are enough young, hot stars ...

Chris Peterson wrote: ↑Thu Mar 17, 2022 1:13 pm In short, it's best not to worry too much about any absolute definition, and just consider what we're seeing in context.

I think you're absolutely right Chris. thanks for your explanations, and also to Ann.

Jac

Swinburne University wrote: The sizes of galaxies are difficult to measure since they don’t possess clearly defined boundaries. Most galaxies simply get fainter and fainter in their outer regions, and the apparent size of the galaxy depends almost entirely on the sensitivity of the telescope used a...

https://apod.nasa.gov/apod/calendar/S_220317.jpg Centaurus A Spanning over 60,000 light-years, ..... << Previous APOD This Day in APOD Next APOD >> Can someone explain to me the conventions used to calculate the size of a galaxy? In purely geometric terms, this is clear to me if the distance and an...

Why does it seem that M66 is listed twice? Good point. Because the artist behind the image likes it so much? :wink: ❤️M66❤️ (Or he got distracted - darn, I forgot to buy milk, and I bet I didn't include M66 among the galaxies in my picture of the observable Universe - better fix that right away...)...

Right. I saw a video the other day from "The Science Asylum", Is the Universe Infinite? . That video demonstrated the nature of our observable Universe very neatly: Start at 1.53 if you want to see how "our past light cone" works. I thought that was a great illustration of what ...

Hi Ignacio, Your pictures are incredibly good and detailed. What kind of software do you work with? Jac Thank you! I use Pixinsight mostly, which has a very accurate RL deconvolution implementation, among many other tools. Ignacio All clear. I also agree with Chris. PixInsight is a great piece of s...

We find these shapes wherever there are dusty nebulas suffering the onslaught of ultraviolet light from hot massive stars. https://live.staticflickr.com/65535/51937453667_2119b44a09_z.jpg Source: Jac Berne (flickr) That's right. Trumpler 14 is an open cluster with a diameter of six light-years, loc...

ignacio_db wrote: ↑Mon Mar 14, 2022 7:33 pm Hi,

I did a similar processing of the Mystic Mountain HST dataset, which also clearly shows evaporating gases around its contour.

Ignacio

Hi Ignacio,

Your pictures are incredibly good and detailed. What kind of software do you work with?

Jac

My pareidolia isn't sharp enough for me to spot the lion in Orion, I'm afraid. So all I can offer is a sleepy lion: https://www.youtube.com/watch?v=friHNUzv-B4 Ann I can also only see the brown mane, but not the lion's face. But for me the horsehead nebula is also a pareidolia resp. a "trojan&...

Fred the Cat wrote: ↑Sun Mar 06, 2022 5:01 pm The remnant is revealing other cosmic curiosities.

Thanks for the interesting link Fred. I think the cosmic heart has slight cardiac fibrillation

The image of the sun takes 500 seconds to get to us. The image of the black disk of Venus takes 136 seconds, i.e. 364 seconds less. It took Venus 25,200 seconds to cross the disks of the sun for 1,045 million km. The diameter of Venus is 12104 km. i.e. to move the distance of one Venus diameter, Ven...

I don't see any particular green tail-like portion, even in the individual (though too small) green optical image at https://hubblesite.org/contents/media/images/2017/21/4028-Image.html. The only tail I see is the one on Messier's drawing! Ok, I was looking for something better on the internet. Her...

https://live.staticflickr.com/65535/51918654675_d9e2370243_z.jpg Source: Jac Berne (flickr) The colors are a free interpretation of the scientific multiwavelenght data. It is interesting that the crab also has a tail (visible in green at the top). Obviously, cosmic explosions don't always spread at...

https://live.staticflickr.com/65535/51918654675_d9e2370243_z.jpg Source: Jac Berne (flickr) The colors are a free interpretation of the scientific multiwavelenght data. It is interesting that the crab also has a tail (visible in green at the top). Obviously, cosmic explosions don't always spread at...

Source: Jac Berne, flickr

Nice core ...

Hi Ann Personally I'm intrigued by a blue-white foreground star masquerading(?) as a supernova.It sure looks like a supernova to me. Probably intuition. SN 1999by was right next to it ;-) However, the star should effectively be a foreground star, since it was already visible in 1999. https://spacefl...