Bad Universe on the Discovery Channel

[Longfellow]

Very well done

I really liked it and am looking forward to future installments.

 

[GreyArea]

Phil knows better than to perpetuate the myth that the asteroid belt looks like the TV/movie version of a bunch of rocks crowded together in space.

But there sure are a lot of them.

Check out the video Phil posted recently at Bad Astronomy. It shows how many asteroids we've discovered, more and more quickly as our tools improve:
http://blogs.discovermagazine.com/badastronomy/2010/08/27/30-years-a-half-million-asteroids/

 

[KingMerv00]

What was the different between Phil's "nuke bullet" and the kinetic impactor test? I'm not questioning the method, I just want to know.

 

[Wowbagger]

What was the different between Phil's "nuke bullet" and the kinetic impactor test? I'm not questioning the method, I just want to know.

My guess is that the nuke would be explosive, blasting the thing apart (or attempting to); wherea the kinetic impactor would not be - it would only shove the thing out of the way on impact.

 

[KingMerv00]

My guess is that the nuke would be explosive, blasting the thing apart; wherea the kinetic impactor would not be - it would only shove the thing away a bit on impact.

Did the bullet explode? I though it was all kinetic energy.

 

[bluskool]

Looks like someone put up the torrent already.

BTW, I watched it last night and really liked it. The Holy Haleakalā line was starting to get annoying after a while, but I definitely could see it being picked up for a season.

 

[Skeptic Ginger]

What sucks is that I don't own a television and there doesn't seem to be any way to watch it on line.

There kind of is. The Discovery Channel site has the program broken up into a gazillion ~2 minute segments. But I imagine the drawback is a commercial to sit through for every segment.

 

[Skeptic Ginger]

Looks like someone put up the torrent already.

Clearly better than the commercial version I just noted.

...The Holy Haleakalā line was starting to get annoying after a while, ...

I agree.

 

[Skeptic Ginger]

Go one light year away, and shoot it with a LONG telephoto lens, and it would indeed look somewhat like that...

My understanding is, no it would not. Got any sources that support your thought here, because I don't want to perpetuate a myth that something is a myth anymore than I want to perpetuate a myth.

 

[Skeptic Ginger]

But there sure are a lot of them.

Check out the video Phil posted recently at Bad Astronomy. It shows how many asteroids we've discovered, more and more quickly as our tools improve:
http://blogs.discovermagazine.com/badastronomy/2010/08/27/30-years-a-half-million-asteroids/

Saw that already on the SpaceWeather web page. Nonetheless, the space between them is analogous to the space between the planets in the solar system. The solar system is often depicted as a small thing with the planets relatively close together, but that isn't close to being to scale.

 

[bokonon]

Go one light year away, and shoot it with a LONG telephoto lens, and it would indeed look somewhat like that...

My understanding is, no it would not. Got any sources that support your thought here, because I don't want to perpetuate a myth that something is a myth anymore than I want to perpetuate a myth.

I didn't see the show, but if it's the usual zero-G rock ring, I'm pretty sure it would. Increasing the distance and using a telephoto will flatten the apparent depth, so lots of widely-separated-along-a-line-of-sight objects would appear to be close to each other.

The telephoto might need to be bigger than the sun to resolve asteroids from a light year away, but in theory I think BenBurch is right.

 

[Wowbagger]

Did the bullet explode? I though it was all kinetic energy.

I assume the bullet did explode, or was meant to. Otherwise, they wouldn't have bothered using a bullet. They could have just used a bar of solid metal.

I suppose it would be best to ask Phil, himself, to confirm; or maybe we could watch the episode again.

 

[Dr.Sid]

Generally I liked the first episode. Anyway the are a lot to improve. First you show that nuclear bomb simulated by impactor would not work .. then you say impactor is the best thing. And they did not mention my favorite methods: nuke from a distance (causing surface vaporization, thus thrust), and surface painting (lowering surface vaporization caused by sun, thus in long term affecting trajectory).

 

[dasmiller]

I didn't see the show, but if it's the usual zero-G rock ring, I'm pretty sure it would. Increasing the distance and using a telephoto will flatten the apparent depth, so lots of widely-separated-along-a-line-of-sight objects would appear to be close to each other.

The telephoto might need to be bigger than the sun to resolve asteroids from a light year away, but in theory I think BenBurch is right.

If you're looking right through the heart of the asteroid belt, the asteroids still cover only a vanishingly small fraction of the view (I'm guessing <1 pixel of a 2 megapixel HD display). If your telescope's FOV is wide enough to have many asteroids in view at once, then they'd be very, very tiny in the image with a total area of ~1 pixel. If your telescope's FOV is so tight that one asteroid makes up a significant portion of the image, then you'd have to be extremely lucky to catch a 2nd asteroid in the same image. It still wouldn't look like the Star Wars asteroid field.

 

[rwguinn]

Generally I liked the first episode. Anyway the are a lot to improve. First you show that nuclear bomb simulated by impactor would not work .. then you say impactor is the best thing. And they did not mention my favorite methods: nuke from a distance (causing surface vaporization, thus thrust), and surface painting (lowering surface vaporization caused by sun, thus in long term affecting trajectory).

The old "Orion" method might work...

 

[Skeptic Ginger]

I didn't see the show, but if it's the usual zero-G rock ring, I'm pretty sure it would. Increasing the distance and using a telephoto will flatten the apparent depth, so lots of widely-separated-along-a-line-of-sight objects would appear to be close to each other.

The telephoto might need to be bigger than the sun to resolve asteroids from a light year away, but in theory I think BenBurch is right.

According to Phil's review of the NEO movie we've been discussing here:

30 years, a half million asteroids

More interesting, to me, is how crowded the asteroid belt looks! But don’t be deceived. The distance between Mars and Jupiter is a bit roomier than depicted in the video. Remember, Mars is about 220 million km (130 million miles) from the Sun, and Jupiter is about 800 million km (480 million miles). That’s a whole lot of real estate: almost 2 quintillion square kilometers (670 quadrillion square miles)! Written out, that’s 2,000,000,000,000,000,000 square kilometers.
Yeah, a whole lot of real estate.
And that assumes those asteroids all lie in the same plane. In fact, many of their orbits are tilted, so we’re really dealing with volume. Even allowing that they may move above or below the plane of the solar system the paltry amount of a million kilometers, that means there’s really 2 septillion cubic kilometers: 2,000,000,000,000,000,000,000,000 cubic km! The volume of the Earth is only about a trillion cubic kilometers, so we’re talking a volume of space that could fit a trillion Earths in it!
So there’s plenty of room for these asteroids....

...Even so, on average, there are millions of kilometers between them!
Space is big. Really, really big.
Despite what you see in this video and in movies, the asteroid belt is not a swarming mess of rocks going every which way. It’s actually mostly empty space.

He sold a tiny bit of his soul for TV effects.

 

[KingMerv00]

According to Phil's review of the NEO movie we've been discussing here:

30 years, a half million asteroids

He sold a tiny bit of his soul for TV effects.

It's possible he didn't see the graphics before it was too late to change. You know how post production is.

 

[bokonon]

According to Phil's review of the NEO movie we've been discussing here:

30 years, a half million asteroids

He sold a tiny bit of his soul for TV effects.

Comment #27 from ChazInMT seems relevant here.

27. ChazInMT Says:
August 27th, 2010 at 11:57 am
I try and educate people regarding size relationships as an astronomer/presenter all the time. The Sci Fi movies, 100% of all science related TV programs, and indeed, this image presented above are grossly out of scale. I have begged in the past that Phil set things straight regarding this and present our solar system to scale on one of his TV ventures. I have never seen the scale of the solar system properly or adequately represented in the main stream media.
Some “Facts of Note” to try and get your head around:
If the Sun were scaled down to a bowling ball in size, the Earth would be a very small 2mm diameter bead orbiting 26 Yards from the bowling ball, Mars is a 1mm bead 40 yards away, and Jupiter is a 22mm diameter marble orbiting 135 Yards from the bowling ball sun. Neptune is a pea sized object 777 Yards out, close to half a mile. On this scale, there would be 10 amazingly small specks of dust representing asteroids per square yard between Jupiter and Mars. Assuming as Phil has that they are about a foot deep, this would be about 1 Asteroid in every cubic foot of space for the 500,000 Asteroids covering an area the size of 10 football fields. If there are 2 million Asteroids, this would still just be 4 specks of dust in a cubic foot of space.
From what I understand, when NASA sends a spacecraft through this “Crowded” asteroid belt beyond Mars, they completely disregard any chance of anything hitting the spacecraft or vice versa, because the probability is so remote.
BTW, let me bounce this off you, if the Earth were a basketball, the crust we live on, and 99% of the atmosphere would each be about 3 sheets of paper thick on average covering the basketball. Earth and Sky are 6 sheets of paper thick. A chicken egg shell is 6 times thicker to scale than our earths crust, food for thought..

To summarize:

4 tiny specks of dust per cubic foot to represent average asteroid density.

Mars 40 yards from the Sun, Jupiter 135 yards, thus 95 yards between them.

Assuming for the sake of argument that the telephoto lens at 1 LY could carve out a 1 cubic foot field of view, we'd be looking at compressing 95*3=285 feet of asteroid belt cross-section into a 1 square foot image. At four specks of dust per foot, that's 1140 specks in our field of view.

Yeah, that's probably not going to look like a floating rock pile unless you take some liberties with the size of the specks. I think you could justify showing half a dozen big rocks cavorting, but more than that would seem unlikely to "line up" properly for the tiny field of view you'd need to make them look menacing.

 

[rwguinn]

The asteroids depicted in that link are the ones we can SEE from Earth, through that damned pesky atmosphere (or from Earth Orbit), which makes them sizable objects, not "specks of dust"

 

[dasmiller]

According to the back of my increasingly-cluttered envelope, if you were looking outward through the asteroid belt, and were projecting the image onto a 2 megapixel HD display, then on average, the total mass of asteroids in the image would asteroids would cover ~1/10,000 of one pixel.

That was assuming the high-end estimate for large (1 km) asteroids (1.7 million), an average diameter of 2 km, ignoring the < 1 km stuff, using an average orbit radius of 2.8 AU out and about 6 deg inclination.

I suspect that the smaller stuff would actually cover more area than the bigger stuff, but I really doubt that it would total more than 1/1000 of a pixel.

A more rigorous approach would be kinda fun but really don't have the time right now . . .