Interesting article. It does verify something I had read a long time ago, which was that Gagarin was trained as a parachutist. During re-entry at some point he popped open the hatch of his Voshkod capsule and jumped into the wild blue yonder. Not sure at what altitude this took place at or whether he was still wearing his space suit, but it’s definitely a strange re-entry scenario. I don’t know if they were afraid of the final impact speed killing the cosmonaut or what, but this seems to be the re-entry mode for the first few Soviet manned flights. They mentioned this in the article about Ilyushin so it lends credibility to it.

Terminology-yechh!

Formulas, math, principles!

Penny

I apologise. In my (weak) defense, they are basically similar and are just terms in the feynman diagram expansion for simple scattering.

Penny

It was an old science fiction trope–dating back to “The Brick Moon” by Nathan Hale!!
( which you can find on the net). There, of course, there was no electronics and humans were needed. They were to send messages via heliostat.

Penny

One poster suggested that we could have had a space station had we followed VON Braun–but why would that have been important?
The main reason for a space station was to do what unmanned satellites do–before we had transistor circuits. Someone had to be up there to change the tubes!!
Space stations are scientifically worthless.
Our current one is a huge boondoggle–as the National Academy of Science has assured us again and again.

And, what exactly is the advantage of building a space ship piece by piece up in space at the space station? You still have to drag the parts up there–and the fuel too.
One could do that –if one wishes too–with the shuttle.

Barton, this is high school physics! Or it was back in the sixties, when I went to High School.
Penny

Why? Because the navigational algorithm needed the inverse of a matrix, and some engineer didn’t understand what that meant–so he entered the multiplicative inverse of each term in the matrix!!

It was embarassing as we televised the launches. That was when, Von Braun
( the Nazi Mass Murdering SS war criminal, who we paperclipped into a national hero)
was given his chance.

Penny

It is a shame that we went with the German monsters for our space program when we could have used Ted Von Karman of Caltech, Robert Goddard, and Jack Parsons.

One reason that the US acted slowly was that Eisenhower, who badly wanted a spy satellite, was unsure of the international law reaction to a satellite going over borders. But, sputnik solved that problem for him.

The real reason that Sputnik was so scary was that Doppler shift from its radio transmitter allowed the Russians to get
a good enough measurement of the earth’s
non-uniform gravity field to get FIRST STRIKE capacity, by getting ICBM’s ( that
B is for ballistic) close enough to destroy our missile launch sites.

Penny

Gee, I’ve never heard that joke…

> I was trying to say that, or ask, maybe, wouldn’t all of US
> rocket technology, and even Russian for that matter, because
> I understand they also took some rocket scientists as well, have
> some basis in German technology?

You are correct for many early vehicles. The US got most of the German design team and their tons (tonnes?) of documentation. The Soviets got most of the unassembled hardware and production equipment left at the Nordhausen “Mittelwerk” assembly area.

If you look at Korolev’s first large rockets after the war, they are direct V2 copies with some bizarre appendages. The SCUD missile is a very close descendant of the V2, with the only significant changes being the shape (to make it easier to manufacture) and changing the fuel from alcohol to kerosene (that’s “paraffin” to you Brits). The thrust chambers were adapted for cluster use in the R7 ICBM, which launched Sputnik, Vostok, Voskhod and Soyuz. The booster (the classic one with the central core and four tapering strap-on’s) is still in use today for all of their manned and most unmanned launches. It is the most successful space launch vehicle every built, and is only one generation removed from the V2.

On the US side, the Redstone missile was von Braun’s “US V2.” It was a direct copy, technologically, including the use of alcohol fuel. Like the SCUD, the shape was simplified for manufacturing. The big changes were in the control system and in the development of a detachable warhead. This is the booster that put Alan Shepard and Gus Grissom into sub-orbit.

Moving on, the Juno (the name of the booster that launched Explorer) moved up to kerosene fuel and other advances. However, that’s where the direct V2 line sort of fizzles out in the US. True, the majority of the design staff at Huntsville (later NASA Marshall) were Peenemunde alumni, but they went new directions. The last gasp of the Third Reich in the US space program was probably the Saturn 1. They wanted to use proven hardware to scale up the boosters quickly. Traveling the same path as Korolev, they lashed 8 Redstone tanks around a central core tank and put 8 large combustion chambers under them. It was derided as “Cluster’s Last Stand” by critics, but it’s the booster that lofted Apollos 7 and 9 into orbit.

If you look at the family tree of US launch vehicles, though, most of the designs today can trace their ancestry back to the Viking sounding rocket of the early post-war period; a design that owes nothing to the Germans.

- Jack

If what you’re referring to is that gold-colored crinkly foil, then it’s irrelevant to to the issue of ionizing radiation. That gold foil is some stuff called “Kapton”, and is for reflecting a broad band of infrared light. It’s heat protection. The Apollo command module had its own variety of such protection. It was a smooth layer of highly silvered mylar, applied in adhesive strips. If you look at pics of the CM/SM taken from the LM, the CM looks very silvery, even mirrored. That’s what it looked like before plowing back through the atmosphere during re-entry.

Dad told a story recently that I hadn’t heard before; it came up when James Van Allen died not so long ago. He said that he and Dr. Pickering, director of JPL, went together to talk Van Allen into putting an experiment on the satellite, which of course resulted in the discovery of the famous Van Allen radiation belts.

So thanks for the recognition of my Dad as a space-age pioneer!

50 years ago today, at 10:48 pm Eastern Standard Time on January 31, 1958, the U.S.’ first satellite was launched. Some items seem to escape mention in many discussions of the event, so let’s talk a bit about the “forgotten history” of Explorer 1…..

Strictly speaking, Geiger counters aren’t “X-ray detectors.” They detect ionizing radiation, of which X-rays are just one type.

More details over on my site,

Sam

That’s exactly what Phil meant by “German Technology”. See my post about a screen back.

- Jack

Gary7

First, Geiger counter CAN detect X-rays because the cause ionization (you know, X-rays are not called ‘ionizing radiation’ for nothing) which triggers the counter.

Second, X-ray range bremsstrahlung (braking radiation) is produced when a particle hits a heavy nucleus.

Imagine that a fast-moving particle is a fast-moving car – if you hit a wall then a driver without a seatbelt will be catapulted through the windshield. That’s also exactly what happens with particles.

However, if a car hit a series of cardboard crates – it will be safely slowed down to a halt. That’s also exactly the thing you want to do with particles.

So Apollo used radiation insulation made from polyethylene, which is made of light atoms (carbon and hydrogen) and doesn’t generate bremsstrahlung.

And no, that doesn’t mean that particles flew right through Apollo capsules. They were (mostly) absorbed in radiation insulation.

BTW, bremsstrahlung is used here on Earth to produce X-rays in X-ray machines in hospitals.

- Jack