Astronomy Picture of the Day -- Into the Void

NASA ^ | June 06, 2015 | (see photo credit)

[SunkenCiv]

Explanation: Fifty years ago, on June 3, 1965, Edward White stepped out of the orbiting Gemini 4 spacecraft to become the first US astronaut to walk in space. White is captured in this photo taken by mission commander James McDivit from inside the capsule as White's spacewalk began over the Pacific Ocean on Gemini 4's third orbit. Planet Earth, spacecraft, and tether are reflected in White's gold tinted helmet visor. A gas powered manuevering gun is held in his right hand. Though the gun ran out of gas after only 3 minutes, he continued to manuever by twisting his body and pulling on the tether for the remainder of the 23 minute long Extra Vehicular Activity. White later described his historic spacewalk as the most comfortable part of the mission, and said the order to end it was the "saddest moment" of his life.

[SunkenCiv]

[Credit: NASA, Gemini Project, James McDivitt]

[SunkenCiv]

It was fifty years ago Wednesday...

The Big One

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[chimera]

Can't do it today, which is sad. Ed White had an easier time on his EVA than Alexi Leonov, who almost didn't survive. White had no problems with his pressure suit, which didn't balloon out like Leonov’s. The Gemini spacecraft was completely depressurized to allow White to exit and enter relatively trouble-free (except for not wanting to end the EVA). Leonov had to squeeze through that primitive airlock device and almost didn't make it back in. In either case, you have to give credit to both men, who have some major cojones to perform what was then an incredibly dangerous maneuver.

[IronJack]

Only to die earthbound two years later when Apollo I caught fire on the launch pad.

[jhroberts]

I have always been confused when I look at pictures like this as to why we are not seeing a plethora of stars in the background.

[RansomOttawa]

Because the objects in the foreground (the earth, White) are orders of magnitude brighter than the stars. If the camera were set up to photograph the starfield, White and the earth would be overexposed. Conversely, if the camera is set up to capture the foreground objects, the starfield is too dim.

[tet68]

It’s cause they were taken during the day time...

[SunkenCiv]

Leonov’s suit inflated nicely due to the near-vacuum, something no one had thought of. That’s one of the risks ya take when you’re better at stealing and copying than at being at the leading edge.

On 8, Armstrong had a jet stick open, which caused the two docked vehicles to bank; first idea was to ditch the Agena, that made the spin worse, but isolated the problem. Naturally, cool hand got it stopped. David Scott, who was there, had been offered the second seat in a sort of offhand manner, “would you like to go on Gemini VIII with Neil?” Anyway, he said they were starting into tunnel vision from the rotation, but “that’s why you send a guy like Armstrong”.

http://www.universetoday.com/99959/memorable-astronaut-spacewalks-show-danger-darin/

[chimera]

They knew that Gemini was going to include EVAs and were as usual so anxious to beat us to the punch that they almost ended up throwing Leonov to the dogs. NASA announced in advance that Kathy Sullivan would do an EVA on STS-41-G. Naturally the Soviets had to beat that and since they had Svetlana Savitskaya already up on Salyut 7 they sent her out first just for spite.

[SunkenCiv]

Thanks chimera, well said. Same thing went for three men in space — the two man capsule they’d been using was altered, seats were moved over each way, and cut down, with a third seat just mounted in the middle. That was done just to “beat” Apollo. The fact is, our space program was better from the bottom up.

[SunkenCiv]

Thanks RansomOttawa. Lol tet68.

[jhroberts]

Thanks for the info. It would be interesting to know what this exact picture would have shown (starwise) if it had been taken on the dark side of the earth.

[chimera]

Thanks for that. The Voskhod 1 spacecraft was a real kludge of a ship. The three crewmen didn't wear spacesuits and the media portrayed it as a great "accomplishment" to fly humans in space in a shirtsleeve environment. The fact is there was no room for pressure suits nor was there payload capacity. Voskhod 2 had them but only because that was Leonov's EVA flight. It is ironic that Vladimir Komorov commanded the clunker Voskhod 1 only to die later in another clunker, Soyuz 1. I'll give the men props for having the guts to fly those things and do things like Leonov did (not that they had any choice), but they sure played it fast and loose with the lives of those guys. But the Russkies always were that way when it came to a choice between lives and the glory of the Motherland.

I like your "cool hand" appellation for Armstrong. His performance on GT-8 was nothing short of remarkable. Once they undocked and knew the OMS thrusters were failed (only one actually), Armstrong knew he had to turn off the OMS circuits and go with the RCS thrusters to stabilize the ship. But he saved himself, Scott, the spacecraft, and maybe a significant delay in the program, which might have happened if the crew was lost. Some people consider the mission a failure since it had to be ended early, but better that than blowing the whole thing. Making those kinds of judgments and decisions while under the kind of stress they were shows a clarity of mind and the ability to handle stress and the unexpected which is extraordinarily rare for ordinary mortals, but commonplace in the world of test pilots and rocket men.

[chimera]

It's tricky, because if you have any kind of object in the foreground to show you are in orbit, even if dimly illuminated, it is enough to throw the exposure settings off so you don't image the stars. If you have nothing in the foreground to show you are in orbit, it looks like a picture you might take from the ground. Here is one of the Big Dipper that the original caption said was taken from the ISS:

Here is another that shows Orion and some other constellations as well as part of the structure of the ISS:

The thing that bothers me about this one is that some of the stars appear to be below the horizon of the Earth. The narrative with the picture says it is due to "refraction" of the atmosphere. I've seen refraction phenomenon but not like this. But I've not been on the ISS so I don't know. Let the reader decide.

[jhroberts]

Thank you for the lesson! You are one of the reasons why websites like this one are so great — the ability to learn new information from other people. Sometimes I feel like I’m back in school! (And that’s a good thing).

[chimera]

It is a good thing, and you get props for having an inquiring mind. The foreground-background exposure issue always comes up with moon landing conspiracy “theorists”: “Why don’t you see any stars in the pictures taken on the lunar surface.” Same answer. The lunar surface is very bright. If the frame includes any portion of it the exposure setting is going to stop down to the point of excluding any dim objects.