Starship Asterisk*

P. Mitchell wrote: ↑Tue Apr 23, 2024 6:08 pm These are not 'contrails'.

They are most certainly the condensation trails produced by passing jet airplanes. Contrails.

from beneath https://www.globe.gov/documents/16792331/47233527/cld_pers1.jpg/f3c94d07-4a38-414c-b856-1566e7e7c5ae?t=1581356571539 Right... but relevance to my comments? ok I am fitting the shadow, the trails and Sun… and you are right, Sun is high in the sky Contrail Shadow X (2024 Apr 23)-.jpg I'm...

I agree with others here that we are seeing the shadows of the contrails cast down onto the clouds, not up. (I'm not convinced it's even possible to have a contrail shadow cast up onto a cloud... the Sun would have to be on or slightly below the horizon, and I think the directly illuminated cloud w...

NGC 2403 This spiral galaxy in Camelopardalis is often compared to M33, but is imaged much less often. Visually, it is a bright binocular object. It is strikingly populated by H II regions, one of which is so large it has its own catalog designation (NGC 2404) inside its parent galaxy. NGC 2403 is ...

I agree with others here that we are seeing the shadows of the contrails cast down onto the clouds, not up. (I'm not convinced it's even possible to have a contrail shadow cast up onto a cloud... the Sun would have to be on or slightly below the horizon, and I think the directly illuminated cloud wo...

Bartolo wrote: ↑Mon Apr 22, 2024 1:54 pm How wide are Mt Etna's smoke rings?

Well, the image was made about 70km from Etna, so given the Moon is a half degree wide, the smoke rings are about 0.08 degrees, and must therefore be about 100 meters across.

johnnydeep wrote: ↑Sun Apr 21, 2024 4:25 pm Two questions about some info from the links:

1. Why does the Jove probe spin - stability I guess? But doesn't that negatively impact the ability to take pictures? And how fast is it spinning?

https://www.jpl.nasa.gov/news/press_kit ... pacecraft/

saturnine wrote: ↑Sun Apr 21, 2024 1:14 pm

Roy wrote: ↑Sun Apr 21, 2024 12:55 pm Could really do better with the William Tell Overture instead of that squirrel music.

I think “Jupiter, the Bringer of Jollity” by Holst is quite appropriate.

Until you recognize that Holst was addressing astrology, not astronomy!

1) it would have been nice to state the date rather than say it was the 16th pass…like that tells us anything. 2) on a personal note, I hate when people add music to space videos. Could really do better with the William Tell Overture instead of that squirrel music. The APODs focus on the “ oh, Wow!...

Hey there, I'm the author of this composite. These images were captured with my lens on a star tracker in Arkansas. The camera was not level at the time of the exposures because I didn't make any adjustments to the camera during tracking by adjusting where the camera was on the right ascension axis...

Alright, I'll ask: why aren't the two "diamonds" on the same line through the center of the eclipse? The centers of the Sun and Moon are coincident at totality, so why aren't the two diamond colinear with the center? The centers of the two bodies are only coincident at mid-totality if you...

But I suppose even if there are only two bodies in a system, like, say, the Sun and Jupiter, the Sun may - and will - change mass over time through its evolution along the Hertzsprung-Russell diagram due to changes in its nuclear fusion processes. So I'd think that could also eventually perturb Jup...

I wonder what makes the comet get too close to the Sun ? I'd imagine gravity pull .. but then, how long it must have taken that comet to reach that stage (i mean how many times it must have made rounds around Sun and how many years it must have been doing it before finally getting too close and get...

I wonder what makes the comet get too close to the Sun ? I'd imagine gravity pull .. but then, how long it must have taken that comet to reach that stage (i mean how many times it must have made rounds around Sun and how many years it must have been doing it before finally getting too close and get...

Superb image, particularly the corona which extends further than in many other images. That's right. But you should always be aware of the spatial conditions. It looks like the corona extends almost to Mercury. In reality, Mercury's orbit is still quite far away... https://live.staticflickr.com/655...

florid_snow wrote: ↑Wed Apr 17, 2024 3:10 pm You missed the "Of these" reference at the start of the sentence. I think the writer was just trying to point out that the comets and Mercury were not visible to the unaided eye. But yes, Jupiter was bright! It must be just out of frame in this image.

Ah. Quite.

Also visible in the image is the sprawling corona of our Sun and the planets Mercury (left) and Venus (right). Of these planets and comets, only Venus was easily visible to millions of people in the dark shadow of the Moon that crossed North America on April 8. Huh? Jupiter was absolutely brilliant...

Does anyone know of a way to display powerpoint slides from the Classroom directly on web pages, without having to download the entire PPT file Candy Crush ? I don't think you can. There are online PPT viewers if you don't have PowerPoint that let you view the slides in a browser, and you can use t...

"shows, unexpectedly, that this red-glowing dust is associated with hot plasma." Is it unexpected because there is plasma inside stars, but this is plasma dust in between stars, as if chunks of plasma were blown out of stars? Plasma is just highly ionized gas. That is, a mix of neutral at...

I can see that the mixture of red and blue light in the sky under certain circumstances will make parts of even in the cloudless dawn or dusk sky look purple (because the atmosphere itself will reflect light and provide some mixing of the colors). I know I have seen clouds reflecting the dawn or du...

<r><QUOTE author="johnnydeep" post_id="338347" time="1713128783" user_id="132061"><s>[quote=johnnydeep post_id=338347 time=1713128783 user_id=132061]</s> <QUOTE author="Guest" post_id="338345" time="1713121809"><s>[quote=Guest post_id=338345 time=1713121809]</s> <QUOTE author="Chris Peterson" post_i...

I had seen several partials but never a total eclipse. I brought cameras along but after about 20 seconds I decided that I wasn't going to live this experience through the lens. There are countless other photographers more able than I to document this. I needed to see this in person and more import...

Once again, the digital sensors just plain maxed out as the sun re-emerged, while in person, the reappearance of the bright disk of the sun, while causing a person to avert their eyes from the brightness, was accompanied by a spotlight shaft of light shooting down from the sky into the circle of da...

Interest - thanks. At times I've often wondered - briefly - why a PNG format file is so much larger than a JPEG and now I know! Never took an interest in the particular formats used in the APODs though. I guess my connection speed is fast enough. 😊 PNG is also the default format that the MS Snippin...

Hello! Today's APOD image is considerably larger in file size than it needs to be, as it's been saved using the PNG format. It should likely be using JPEG instead. I am referring to the image at this path: https://apod.nasa.gov/apod/image/2404/pinholepalm1024.png I have confirmed I can download the...