Click on the image to enlarge
Good afternoon everyone.
The object resembling a ball-bearing in the photo above is ECHO-1a, America’s first passive communication satellite and the first half of the ECHO experiment. It was a rather large (100 feet in diameter) metalized 0.5 mil Mylar balloon. ECHO-1 was to be used to bounce microwaves from one point on the ground to another, but the Delta rocket it was riding on second stage went wonky (scientist-speak for “Hey! It’s not supposed to go in that direction!”) and the range officer blew it up. This was in 1960 and the rockets that were used at the time by the US space program tended to behave more like fireworks than lift vehicles, and range officers had a lot more to do then than they do now. So the first ECHO satellite that made it to low earth orbit was ECHO-1a launched on a Thor-Delta in mid-May, 1960. On August 12 of that year, JPL in Pasedena pinged Bell Labs in Homdel (that’s in New Jersey, evidently) with a microwave signal, and there was much rejoicing.
The military used the satellite to provide astronomical reference points in order to accurately drop nukes on Moscow if the occasion arose, at least once they had a ballistic missile that would actually get there.
During ground testing, it required 40,000 pounds of air to fill the 150 pound ECHO-1 according to NASA, which sounds like an awful lot of weight to me. I could work out the calculations, but the Emmas are pissed at me right now for saying something insensitive (again) and are off at the test range blowing things up, and I don’t feel like wasting my time. I’m just happy that they’re finally getting their anger issues somewhat under control. It was getting tiresome (and expensive) rebuilding my office once or twice a month due to real or imagined slights on my part. And they wonder why I don’t spend much time at the labs anymore…
Anyway, it evidently took a shitload of air to inflate the things on the ground, but only a few pounds up in LEO. NASA also took into account the fact that the balloon would be frequently holed by micrometeorites and drifting bits of exploded American rockets, so they had an onboard system that consisted of sublimating chemicals to keep the balloon inflated. It worked fairly well too, as ECHO-1a remained in orbit and usable until it finally de-orbited on May 24, 1968, and astronomers around the world cheered because the damned overly bright piece of junk wouldn’t interfere with their observations any longer.
It took me a minute to notice the satellite's surroundings and really comprehend its size. That is a really big balloon.
Also, am I the only one whose brain kept transforming ECHO-1a into ECTO-1a?
If I'm thinking correctly, the photograph must have been taken by a guy way over in the corner by the door, between the high and mid row of windows, with a dirty great telephoto lens. That's where there's the least convex distortion. I know objects in the mirror are closer than they appear, but it still looks to be a hundred yards from the ECHO-1a to the corner.
How come the guy taking the photo has no reflection? Also, I am glad too see they are using Pure Carbonic, not that weak 50-50 mix junk.
It's the same guy who took the pictures "on the moon"…
Inflating it while sheltered from the wind strikes me as cheating.
Bah, you're just whingeing because you don't have NASA's budget for your rocket program. Hmm, now that I think about it, I don't think NASA does either because congress cut them off at the knees or something.
Maybe so, but at least our balloons don't bear a surprising resemblance to Carl "Alfalfa" Switzer.
<img src="http://vargen57.unblog.fr/files/2009/05/carlalfalfaswitzer.jpg">
You, my dear sir, have a weird mind. As a Science Professional, I advise you to stop tasting the rocks that you find.
/and you made me laugh
I only taste the rocks that I don't recognize. Or those that I already know taste good. It's a recognized technique.
http://books.google.com/books?id=jG4NAAAAYAAJ&…
Here's some nice candy-like realgar for you! Yummy! I'm sure you know the secret flavor ingredient.
<img src="http://upload.wikimedia.org/wikipedia/commons/5/52/Realgar-229713.jpg" width="300/">
No, thanks. Realgar tastes like AsS.
I'm sure it does.
I had a mechanic tell me the quickest way to diagnose a leak was to taste it.
I haven't taken him up on his advice.
Was this picture taken inside Hangar one at Moffet?
I just found this with Tineye:
An Echo communications satellite is undergoing a test inflation in a blimp hanger in Weeksville, North Carolina. http://www.astrophysicsspectator.com/commentary/c…
I remember as a little kid our family going out into the back yard one day with binoculars to watch the Echo satellite go by overhead. It was visible from the ground with the naked eye. Even in a bright blue sky one could make out the spherical shape.
Now I'm wondering how the signal was reflected. On the near side it would tend to scatter everywhere, and if it passed through to the inside-opposite it would tend to get… um, scattered all over the place again, except also focused a bit, on something.
Can we have emoticons with their eyes dilated and slightly splayed?
That yellow crane truck on the far side looks like it might spring like a scorpion and pop the ECHO-1a.
And what are those little Army fuselage shaped objects in the lower left? Gliders I'm thinking.
they look like Piaseki "Flying Bananas". And there may be a Sikorski helo
over on the other side, in brown primer, nose out.
One could be, awfully small looking at that distance though.
<img src="http://planesandchoppers.com.s3.amazonaws.com/15256.jpg" width=600>
The tail in the foreground looks like an airplane slightly larger than the crane truck, and the tail in the back seems like another helicopter.
Well, it is a rather large condom…..
I felt like wasting my time:
Volume of a sphere: 4/3 * Pi * R^3.
for a radius of 50ft, that's 523,599ft^3. Weight of air I'm going to say is .0807lb per ft^3 because this answer is longer than this one.
523,599 * .0807 = 42,254 lb
(if you use the figure from the second link*, it's 39200-something. ish.)
*at room temperature, given that the balloon is in a room
Hmph. You'd think that something with that much mass would have the decency to at least sit on the ground when at rest. (Yes, yes, I know)
/Thanks for your efforts. It never hurts to double check NASA's numbers for them.