Starship Asterisk*

Take the comparison of 3 million light years to 3 ten-thousandths of a light second - what is that for? (The latter number works out to 5.6 miles and so is probably wrong, too many decImal places, as that meteor track is most likely starting at least 50 miles up) By my calculations 0.0003 light sec...

The Earth appears to have photographic diffraction spikes in this image. But the diffraction spike on the right appears to be a tiny bit "fatter" and a tiny bit brighter and differently colored than the diffraction spike on the left. Voyager I has two cameras, a narrow-field one and a wid...

Indeed, the color is due to the composition of the meteor (and of the atmosphere). And if we had a spectroscopic data, we could say a lot about what the meteoroid was made of. But with only three broadband channels (red, green, and blue) we really don't have much information. The colors of the trai...

I am more amazed by everything else other than the galaxy and the colored lighted meteorite streak. Look at the number of objects in visible light. I'm not seeing any refraction spikes etc, so assuming every single light blob is some galaxy. Yes ? How many ? 1000s.. Seems denser than deep/ultra dee...

The Earth appears to have photographic diffraction spikes in this image. But the diffraction spike on the right appears to be a tiny bit "fatter" and a tiny bit brighter and differently colored than the diffraction spike on the left. Voyager I has two cameras, a narrow-field one and a wid...

I am of course wondering about the very red-colored dust coming off the meteor. I'd like to ask Chris why this dust is so red, but I know that he would only say that the color is due to the composition of the meteor, and since he himself knows nothing about the composition of this meteor, he can't ...

whwiii wrote: ↑Sat Jul 13, 2024 9:08 pm forgive me if obvious, but what do "EV" and "J" stand for?

"EV" labels the frame that contains both Earth and Venus. "J" labels the frame that contains Jupiter.

Uh, a "60 frame mosaic"? I count only 38. Also, just to be clear, the only object actually visible in any of these frames (other than the insets) is the Sun, which is the large bright spot near the center of the arc of frames, and whose bright rays appear in other nearby frames. Correct? ...

hankbernath@msn.com wrote: ↑Fri Jul 12, 2024 2:12 pm what is the ringed object in the lower right of the image displayed?

The logo of the imagers?

Except it's not likely that many stars in a globular cluster have planets. The view from inside a rich globular cluster might be something like this: Inside 47 Tucanae William Harris and Jeremy Webb.png Inside globular cluster 47 Tucanae. Illustration: William Harris and Jeremy Webb But Chris is ri...

The distance to the center of the cluster is known with very high accuracy (5.24±0.11 kpc based on Gaia parallax) so the positional shifts of seven stars close to the center yield accurate radial velocity values, which define minimum 3D velocities. As those velocities are greater than the cluster e...

Fast-moving stars around an intermediate-mass black hole in ω Centauri The fastest and the centremost star (Fig. 1, star A) has a 2D proper motion of 4.41 ± 0.08 mas/yr (113.0 ± 1.1 km/s). This is higher than the escape velocity of the cluster if no IMBH is present, v_esc = 62 km/s. The combined co...

Ham Todd wrote: ↑Thu Jul 11, 2024 4:00 pm I often wonder what the sky would look like for a person living on a planet that orbited around a star in this cluster! I'm pretty sure the view would be awesome!

Except it's not likely that many stars in a globular cluster have planets.

This article says that "super Earths" might actually be better at fostering life than our puny little Earth, due to more plate tectonic activity and the greater ability to hold on to an atmosphere, both due to the higher gravity and internal heat. (But I'm not quite convinced: a thicker a...

This article says that "super Earths" might actually be better at fostering life than our puny little Earth, due to more plate tectonic activity and the greater ability to hold on to an atmosphere, both due to the higher gravity and internal heat. (But I'm not quite convinced: a thicker a...

Comet 13P/Olbers This Halley-type comet with a period of 69 years just passed perihelion a couple of weeks ago. Captured here is the typical green glow of the coma (from CN and C 2 emissions) and reflected sunlight from a diffuse trailing dust cloud. Very prominent is the blue ion tail which shows ...

I was so crushed yesterday after I lost a long post that I had spent hours composing, so that after I had mostly restored that post, I couldn't bring myself to make another. But I really wanted say that the most common type of exoplanets (of those that we have so far detected) are neither "Jup...

As you can see, WASP-12b is egg-shaped due to its proximity to its parent star. Yes, but both the APOD and illustrator Robert Lea (who illustrated the SPACE article about WASP-12b) got the planet's color wrong! https://upload.wikimedia.org/wikipedia/commons/thumb/8/80/The_Pitch-Black_Exoplanet_WASP...

If you love clouds and you love astronomy then no matter what condition the sky, you'll enjoy a look up after sunset! But I also love nitpicking... today's APOD says that iridescent clouds are "relatively rare" but they are actually very common. If there are no clouds, you can't see iride...

johnnydeep wrote: ↑Sat Jul 06, 2024 11:41 pm Ok, where are the "small telescope views" that show "nested rose petals"?

https://knuklhdsobsrv.wordpress.com/wp- ... etch-1.jpg

EDIT: Okay! I couldn't help myself. I googled "Trumpler 5 age" and got a few different answers, among them Log Age, 9.61. (What does that mean, Chris? I have an idea, but I think that would perhaps make the cluster too old.) It means log(age in years). So 9.61 means 4.07 billion years, si...

What kind of explanation is "before" not having any meaning in the context of the universe? The entire illustration is a timeline of the universe. That doesn't mean there's a "before". That word is pretty hard to define when time doesn't exist. I'm reminded of the "What did...

Avalon wrote: ↑Wed Jul 03, 2024 2:40 am What kind of explanation is "before" not having any meaning in the context of the universe? The entire illustration is a timeline of the universe.

That doesn't mean there's a "before". That word is pretty hard to define when time doesn't exist.

True enough, given SF-levels of engineering. With 0.01 to 0.1 C being the fastest a realistic vessel can move in the real univese, given the limits of real engineering, relativistic tiime compression inside the vessel isn't much of a factor. And you're entirely correct about the travellers not havi...

So, so many questions. What IS outside of time, like before the BB? How is it that humans existed for millions of years and the formation of cities only during the last 10,000 years? Were they without any intelligence or social skills before that? How convinced are we about the Theia event? How are...