Starship Asterisk*

Thanks. Any information about a timetable (and/or funding) for such a space-based detection system? The closest for now is ESA's NEOMIR, which is still in the early stages and not guaranteed to happen. And it's not a complete warning system, but more of a supplement to existing ones in that it shou...

Thanks, Chris. Let's hope we never need to use it. I forget the title of the film that dealt with this topic, but, as I recall, it struck me as being perhaps a bit too close to reality for comfort regarding the way people reacted to the situation. Until we have a fully space-based detection system,...

Thanks, Chris; that's helpful. It's far from clear (to me at least) how the 13-day early warning (16 June - 29 June) might have been used had the asteroid been on a collision course with a heavily populated area. Are you aware of preexisting plans that might have been implemented? Can't help wonder...

The Earth doesn't rise over the Moon unless the camera is moving. The video shows the camera as stationary. Bad video. The Moon is tidal lock to the Earth. That means the Earth's position is fixed at the same azimuth and zenith. To get the Earth to rise, the camera must be moving toward the Earth. ...

How much damage would Asteroid 2024 MK have caused if there had been a direct impact? How would it compare with the well known Tunguska Event, for example? Can we offer any informed speculation on that? Thanks. Depends on what it's made of and what kind of trajectory it enters on. Iron and steep an...

I was dismayed to read yesterday (27 June 2024) that Asteroid 2024 MK, measuring between 120 and 260 meters, was first discovered on 16 June 2024, and that it will pass within 290,000 kilometers (180,000 miles) of earth on 29 June 2024. For publicly available details, please see: https://www.earth....

0.jpg Perusing around today's APOD is something. Does anyone know what this is? I assumed a star rather than a galaxy, but are the blue areas anything other than light tricks from Webb's camera? A bright (by JWST standards) star, almost certainly. And all the structure around it looks to be diffrac...

Pictured here, the Dark Doodad Nebula sweeps across the center of a rich and colorful starfield. Its dark color comes from a high concentration of interstellar dust that preferentially scatters visible light. While there is a little bit of scatter around the blue star and perhaps a few other bright...

How large is a piece of the dust. Is it hot? If not, then there is no chance of it to conglomerate and form a star. The dust size follows some kind of power law distribution. The smallest will be just a few molecules, the largest a few tens of micrometers. The temperature of the dust depends on its...

Some parts of the name puzzle me. "JADES" is an acronym for "JWST Advanced Deep Extragalactic Survey". But what dose "GS" mean? And with a redshift of z = 14.32 why the "0" in "z14-0"? The previous record holder, JADES-GS-z13-0, has a redshift of 13...

>...Everything is getting further apart, not closer together If that is indeed the case, then there should be fewer galaxies visible in the same region. I'm just impatient, I hate waiting millions of years for the most distant observable galaxies to either vanish or new ones to appear in a falsifia...

How is it that when looking north, east is to your left? Not on any compass I've ever seen. Is this photo a mirror-reversed image? If you lay on the ground, with your head to the north, east is to your left. Stellar coordinates mirror terrestrial coordinates because instead of being drawn on the ou...

https://apod.nasa.gov/apod/calendar/S_240622.jpg Lynds Dark Nebula 1251 Explanation: Stars are forming in Lynds Dark Nebula ( LDN ) 1251. About 1,000 light-years away and drifting above the plane of our Milky Way galaxy, LDN 1251 is also less appetizingly known as "The Rotten Fish Nebula."...

If Hubble made the same observation of the Deep Field horizon today, would a new image reveal galaxies that were not yet visible thirty five years ago? Is 35 light years a reasonable distance between the most distant galaxies of the original image? -(signed) Congenitally Clueless In cosmological te...

I was musing on the world of 1990, when Hubble was launched. The telescope has outlived much of its contemporary technology. Cassette tapes and CDs, pay phones and landlines, huge actually floppy floppy discs and their 3.5" counterparts, loud squawky modems and dialup internet have all gone th...

Looking at the scale, it looks like NGC 1546 is quite small, no? How small can a spiral galaxy be? This looks to be 40-50K ly across, which is pretty typical for spiral galaxies. Maybe a bit on the low end, but not unusual. FWIW, this isn't a spiral galaxy, but a lenticular galaxy. We might compare...

Sorry, tangential thought that is top of my mind looking at the photo.. Those "direction" arrows.. I've always wondered how and why someone would feel/decide - and obviously I'm assuming the whole scientist community agreed to - a specific direction as North/East/South/West.. When someone...

The same mysterious nebula was depicted ten years ago (https://apod.nasa.gov/apod/ap140718.html). But then, the "telltale blue emission from doubly ionized oxygen" was not blue but very clearly green! So, which is the correct colour aand why? The blue color is not true. What we see is OII...

The elongated blue (ionized OIII) nebulae have the same configuration with central star and explosion out fore and aft ends. Why would you doubt, if I am reading your post correctly, that they are the same mechanism? Orientation will probably ensure that some nebulae are pointed at, or away from us...

The same mysterious nebula was depicted ten years ago (https://apod.nasa.gov/apod/ap140718.html). But then, the "telltale blue emission from doubly ionized oxygen" was not blue but very clearly green! So, which is the correct colour aand why? Doubly ionized oxygen emits light at 501nm, wh...

Maybe I'm wrong, but that "jet" of material looks exactly like a low Reynolds number smoke simulation. I happen to have more than a decade of painful experience with numerical simulations of turbulence. The rule of thumb for analysis via Reynolds number is that you measure the characteris...

And why is that? When I think of this event I picture the likely less massive object - the star - doing the falling into the likely larger object - the black hole. The black hole is tiny compared with the star, and of similar mass. Your statement may be true for normal black holes. However, the ani...

It's quite rare, but it would be fun to see a simulation of a star falling straight into a black hole, a direct hit as it were. It probably makes more sense to visualize that scenario the other way around... a black hole falling straight into the star. And why is that? When I think of this event I ...

richardschumacher wrote: ↑Sun Jun 16, 2024 1:56 pm It's quite rare, but it would be fun to see a simulation of a star falling straight into a black hole, a direct hit as it were.

It probably makes more sense to visualize that scenario the other way around... a black hole falling straight into the star.

I'm sorry to say, to me, this looks more like a sci-fi movie, super exaggerated dramatic, with all kinds of visual and audio effects (music) to make this even waaaaaaaaaaaay more explosive and dramatic than how in reality it'd be (as per many books and articles and scientists and presentations I've...