Starship Asterisk*

If one is going to map grayscale to a color scale, why limit ourselves to just purple or orange, when we could have both? The perceptually uniform colormap "plasma" or "inferno" freely available from matplotlib might look really good, and they seem appropriately named.

"When's your birthday?"
"April 11th"
"What year?"
"Every year!"

Haha I agree it might be a little too close up. I used to do Jupiter sketching when I had access to an 8" refractor, always in black and white though, never attempted color. Sketching really adds to the observing experience, I think. Remember that blue storm that blew up briefly on Saturn? I th...

Imagine if it started ticking down: "Astronomers report giant 37 in the sky is now a 36 - wait - this just in, it's 35!" Haha, feels like something that could've been in Clarke's "Nine Billion Names of God"

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.

I saw this eclipse and the bright pink prominences were stunning, and it got me reading about H alpha emission. And after some reading, I feel betrayed by every "H alpha" filtered photo of the sun I have seen. Because the prominences appeared obviously PINK to human eyes, doesn't that mean...

I was also near Indianapolis, the thin cirrus blanketing the entire multi-state area made comet viewing likelihood near zero. The comet's position was about at 10 o'clock with respect to the sun from that location. Venus was bright, Jupiter was visible, and the prominences and corona were still stun...

I've always loved this image, but I feel compelled to make a "well, actually" comment, please forgive me, but I don't think the word "coincidence" is appropriate and instead one could conceivably substitute "inevitable" because of the caveat that we have a Full Moon, no...

A key phrase here is "aerosol susceptibility" because broadly speaking, there is a large contrast from land to ocean for the amount of particulate matter floating in the air - aka the aerosol concentration is much higher over land than over the ocean. So running your SUV does not cause thi...

I plan on shooting images around local noon on the 21st, which for me will put them in the southeastern sky just past their point of being closest (which is slightly before they rise for me). Both of these objects are plenty bright to be telescopic objects in full daylight. I'll go for wider field ...

Has anyone ever been able to take a shot capturing all six of our system's largest moons (plus Jupiter and Saturn of course) in the same frame? Such a photo opp might have been possible back in April. If you're up late in the coming nights, you may want to pay attention to the waning gibbous moon —...

+100 points to whoever came up with "arachnologically correct"

The majority, perhaps all researchers who study weather and climate phenomena on other planets and moons were either conventionally trained meteorologists who transtitioned to this type of planetary science, or atmospheric physicists who did so. Of course, some of them now have students who are ent...

I would like to defend the position that meteorology and astronomy (and history!) are different fields. Of course they are (well, history doesn't fit here simply because it's not a branch of science). Meteorology is a subdiscipline of atmospheric and oceanic physics, which is also a subdiscipline o...

If I find a flint arrowhead, I assume the ancient archer is not nearby. If I decipher a neutrino in Sudbury, I assume the generating entity is not in the mine. In other words, because one perceives astronomical evidence does not allow one to classify it a s current events. That is why I disregard t...

I would like to defend the position that meteorology and astronomy (and history!) are different fields. Perhaps we are all trying to express the importance of the history of the separation of scientific fields. I am a meteorologist and I appreciate APOD's expression of the fuzziness between these fi...

That's a fun picture. This is a fun one! There's an element here of the photographer "playing" with the light, and I think it's lovely! Seeing this comet and solar system light in the presence of such ancient light; it's like hearing a quick flute melody fitting perfectly with the deep no...

GCV Of Course I Still Love You <Broadcast>:: You engaged your sub-light drive??! FCS 'Oumuamua <Tight beam>:: Don't worry, my excess motion is within the error of their instruments. OCISLY:: You'd be surprised what they can do with mathematics and their calculation machines. 'Oumuamua:: Don't lectur...

Here's my own follow up question to Steve Basten's. What is space, that it stretches so much that two objects within view of each other eventually appear to disappear? I only just barely understand special relativity (I think). How can space itself be expanding (on its own), if distance itself can o...

What does "Vit Drite" mean? Ann From a quick google search, I think its Albanian for "light year". To be honest, I didn't even know that Albanian was a language, but I learned a little context from this very nice wikipedia page https://en.wikipedia.org/wiki/Indo-European_languag...

... There are in fact 2 animations at play simultaneously. The clouds evolve accelerated about 2 million times their normal speed independently of the rotation of the planet. /*Peter R ... which gives the impression that the central equatorial band of clouds is orbiting at an incredible speed. But ...

This is beautiful. I feel the wonder of the planets, the hope in scientific pursuit, and the love in a community effort. Thank you Peter Rosen and all the contributing observers from all over Earth. Thank you APOD team. Thank you for posting a beautiful and inspiring comment, which was even more lo...

This is beautiful. I feel the wonder of the planets, the hope in scientific pursuit, and the love in a community effort. Thank you Peter Rosen and all the contributing observers from all over Earth. Thank you APOD team.

Even though it's well below the "freezing temperature" water up there, contrails (like other high altitude clouds) can actually be made of mostly liquid droplets, "super-cooled", they might freeze eventually but for a while that cloud is made of liquid, multiply scattering light ...

Very interesting! I think the contrail is at higher altitude than the ice layer the whole time, and it looks reasonably fresh, probably made of mostly small liquid cloud droplets, which do multiple scattering of the sunlight, bouncing it all around so there's no wavelength dependence and it appears ...