Oh Dear! SpaceX rocket explodes after launch

[Ishkabibble]

For Apollos 8, 10, 11 and 12, the excess LOX on the S-IVB was vented in a forward direction to slow the stage down. This allowed the moon to cross its path before it got there, so it swung around the trailing "edge" of the moon. The moon dragged it along in its orbit, acting as a slingshot to eject it into an earth escape trajectory so that they went into independent orbits around the sun -- where they remain today.
...
For the early missions that used the free-return trajectory, they almost certainly looped around the moon, returned to earth and hit the atmosphere. I'm not sure about the later missions, but they're likely in solar orbit.

I don't mean to derail the thread, but there has to be a way to calculate exactly where these things are today, isn't there?

I mean, if the velocities, attitude, inclination, and locations of all of the spacecraft were known when the stagings occurred, (and at the time, they had to be, didn't they?) then someone who knows what they're doing should be able to calculate the physical location in orbit of these pieces of hardware.

If JPL could calculate where Pluto was going to be 9 years before the launch of New Horizons, and only miss it by 7 seconds, and its 3.8 billion miles away, then the positions of the Apollo stages ought to be able to be calculated.

It would be nice if something like this were in Stellarium or something. I don't know if my 'scope could resolve something that small, and I don't think it could, but it would be pretty cool to know where to look.

[bknight]

For Apollos 8, 10, 11 and 12, the excess LOX on the S-IVB was vented in a forward direction to slow the stage down. This allowed the moon to cross its path before it got there, so it swung around the trailing "edge" of the moon. The moon dragged it along in its orbit, acting as a slingshot to eject it into an earth escape trajectory so that they went into independent orbits around the sun -- where they remain today.
...
For the early missions that used the free-return trajectory, they almost certainly looped around the moon, returned to earth and hit the atmosphere. I'm not sure about the later missions, but they're likely in solar orbit.

I don't mean to derail the thread, but there has to be a way to calculate exactly where these things are today, isn't there?

I mean, if the velocities, attitude, inclination, and locations of all of the spacecraft were known when the stagings occurred, (and at the time, they had to be, didn't they?) then someone who knows what they're doing should be able to calculate the physical location in orbit of these pieces of hardware.

If JPL could calculate where Pluto was going to be 9 years before the launch of New Horizons, and only miss it by 7 seconds, and its 3.8 billion miles away, then the positions of the Apollo stages ought to be able to be calculated.

It would be nice if something like this were in Stellarium or something. I don't know if my 'scope could resolve something that small, and I don't think it could, but it would be pretty cool to know where to look.

Most of the later missions impacted the lunar surface to give the scientists a seismic event to collate.
http://nssdc.gsfc.nasa.gov/planetary/lunar/apollo_impact.html
EDIT2add impact site link.

[Allan F]

For Apollos 8, 10, 11 and 12, the excess LOX on the S-IVB was vented in a forward direction to slow the stage down. This allowed the moon to cross its path before it got there, so it swung around the trailing "edge" of the moon. The moon dragged it along in its orbit, acting as a slingshot to eject it into an earth escape trajectory so that they went into independent orbits around the sun -- where they remain today.
...
For the early missions that used the free-return trajectory, they almost certainly looped around the moon, returned to earth and hit the atmosphere. I'm not sure about the later missions, but they're likely in solar orbit.

I don't mean to derail the thread, but there has to be a way to calculate exactly where these things are today, isn't there?

I mean, if the velocities, attitude, inclination, and locations of all of the spacecraft were known when the stagings occurred, (and at the time, they had to be, didn't they?) then someone who knows what they're doing should be able to calculate the physical location in orbit of these pieces of hardware.

If JPL could calculate where Pluto was going to be 9 years before the launch of New Horizons, and only miss it by 7 seconds, and its 3.8 billion miles away, then the positions of the Apollo stages ought to be able to be calculated.

It would be nice if something like this were in Stellarium or something. I don't know if my 'scope could resolve something that small, and I don't think it could, but it would be pretty cool to know where to look.

Problem is, the "play" in the accuracy of the vectors add up over time, so at present day, only approximations are possible. 40+ years of free travel leads to big error margins.

[Peter B]

For Apollos 8, 10, 11 and 12, the excess LOX on the S-IVB was vented in a forward direction to slow the stage down. This allowed the moon to cross its path before it got there, so it swung around the trailing "edge" of the moon. The moon dragged it along in its orbit, acting as a slingshot to eject it into an earth escape trajectory so that they went into independent orbits around the sun -- where they remain today.
...
For the early missions that used the free-return trajectory, they almost certainly looped around the moon, returned to earth and hit the atmosphere. I'm not sure about the later missions, but they're likely in solar orbit.

I don't mean to derail the thread, but there has to be a way to calculate exactly where these things are today, isn't there?

I mean, if the velocities, attitude, inclination, and locations of all of the spacecraft were known when the stagings occurred, (and at the time, they had to be, didn't they?) then someone who knows what they're doing should be able to calculate the physical location in orbit of these pieces of hardware.

If JPL could calculate where Pluto was going to be 9 years before the launch of New Horizons, and only miss it by 7 seconds, and its 3.8 billion miles away, then the positions of the Apollo stages ought to be able to be calculated.

It would be nice if something like this were in Stellarium or something. I don't know if my 'scope could resolve something that small, and I don't think it could, but it would be pretty cool to know where to look.

My guess is that one confounding factor would be the gravity field of the Moon. We know it's lumpy, but how well can it be modelled to determine how it would affect the S-IVBs as they slide by? And the old chaos theory - it only takes a small change in the initial conditions to lead to a very different outcome 40+ years later.

[ka9q]

That's right -- these trajectories are highly "chaotic" in the formal sense that small uncertainties in initial conditions lead to big uncertainties in state (position, velocity) over time.

There are quite a few pieces of Apollo hardware in solar orbit. The ones I can think of:

Apollo 8 S-IVB
Apollo 9 S-IVB (relit in earth orbit into escape)
Apollo 10 S-IVB
Apollo 10 LM (Snoopy) ascent stage
Apollo 11 S-IVB
Apollo 12 S-IVB (made a temporary return to earth orbit in the early 2000's)

Beginning with Apollo 13, the S-IVBs impacted the moon.

[Allan F]

Reminds me of the "Mythbusters" episode, where they tried to walk in a straight line - blindfolded.

[Ishkabibble]

Well, dang... I was looking for a reason to pull that 10" Dobsonian monstrosity out of the garage.

Oh well... I guess there could be something interesting to look at, planetary-wise.

[ka9q]

Well, dang... I was looking for a reason to pull that 10" Dobsonian monstrosity out of the garage.

While the Apollo 12 S-IVB was temporarily caught in Earth orbit a decade ago, it was only 16th magnitude. Pluto is typically a couple of magnitudes brighter. Can you see it?

[Ishkabibble]

Well, dang... I was looking for a reason to pull that 10" Dobsonian monstrosity out of the garage.

While the Apollo 12 S-IVB was temporarily caught in Earth orbit a decade ago, it was only 16th magnitude. Pluto is typically a couple of magnitudes brighter. Can you see it?

I honestly don't know, but probably not.

Let me expand on that by saying that I hoped I was looking at Pluto, but to be perfectly honest, I couldn't say with even 50% certainty that I was. I had to take someone else's word for it.    I went to a star party several years ago that was put on by a college in a neighboring state. I took my Dob, but it was by far the smallest scope there. Ended up looking through some guy's 18" Obsession. He said it was Pluto, but all I saw was a fuzzy pinprick of light. I probably couldn't resolve an S-IVB with my 10" even if it was in lunar orbit. I didn't even think of it that way. In fact, I should have known better. The thing is only about 60 feet long.

[ka9q]

I think the only way you could really definitively confirm either object is to take a time exposure, then confirm both the position and just as importantly the proper motion of the object as what they should be.

[Ishkabibble]

I think the only way you could really definitively confirm either object is to take a time exposure, then confirm both the position and just as importantly the proper motion of the object as what they should be.

Can't take photos with a Dob.

At least, not easily, and not with mine. The eyepiece-to-camera interface throws off the focus, and there's no way to manually track with the type of mount I have with enough accuracy to follow anything. Oh, they have those "Barn Door" type equatorial platforms, but I'm not mechanically-inclined enough or patient enough to try to build one.