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Voyager 2 is back online after eight months of radio silence

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Re: Voyager 2 is back online after eight months of radio silence

#81
post #59
post #4

Earlier quoted context omitted.

Our hacks are nothing compared to the hacks of these old school nasa programmers :) The amazing thing (to me) is that they developed the Voyager spacecraft in an era when space flight wasn't hugely popular and the budgets at NASA were being cut regularly. NASA went from a peak of $6bn a year in the mid-sixties under Johnson to almost half that under Ford and Nixon. The engineers were well-respected and they clearly f…

We spent more money under Nixon and Ford than we do now. You’re not familiar with how much money as a percentage of GDP we spent in the 1960s? It’s noteworthy. https://en.m.wikipedia.org/wiki/Budget_of_NASA#Annual_budget We were building the Space Shuttle and exploring the planets. I wish we could spend money on NASA like we did in the 1970’s

I wish that the problem were money alone.

In the 60s, they were pushing to get things out and accepted risk levels that today we would consider intolerable.

Today we've developed a cost-plus contracting approach plus insane safety and success standards that mean it is almost impossible to actually get anything done. With one notable exception - SpaceX.

Just throwing money into Boeing and Lockheed these days would generate profits for them, but not a lot of science for us. We need to change culture as well.

Re: Voyager 2 is back online after eight months of radio silence

#82
post #76

Earlier quoted context omitted.

What good does a high exhaust velocity if your fuel stays all inside the ship?

As long as we are talking hypothetical designs, you can use spent nuclear fuel as reaction mass an ION engine just fine. That said, weight wise it’s fairly trivial so you could just eject it. Project Orion is detonating nuclear weapons which consist of far more than just fuel, they also need high explosives etc, however much of the fuels energy is wasted both from low yield bombs being less efficient but also simply…

> Nuclear powered ION engines however would be ejecting far more of their reaction mass of say xenon per KG of fuel that leftover fuel is basically irrelevant.

Wait, if that is true, then the ION engine has a lower ISP than direct explosions, not higher. Unless the reactor is orders of magnitude more efficient than the bombs.

Re: Voyager 2 is back online after eight months of radio silence

#83
post #59
post #4

Earlier quoted context omitted.

Our hacks are nothing compared to the hacks of these old school nasa programmers :) The amazing thing (to me) is that they developed the Voyager spacecraft in an era when space flight wasn't hugely popular and the budgets at NASA were being cut regularly. NASA went from a peak of $6bn a year in the mid-sixties under Johnson to almost half that under Ford and Nixon. The engineers were well-respected and they clearly f…

We spent more money under Nixon and Ford than we do now. You’re not familiar with how much money as a percentage of GDP we spent in the 1960s? It’s noteworthy. https://en.m.wikipedia.org/wiki/Budget_of_NASA#Annual_budget We were building the Space Shuttle and exploring the planets. I wish we could spend money on NASA like we did in the 1970’s

I don't see anything on that page given as a percentage of GDP, just percentage of federal budget, and inflation adjusted. And while the inflation adjusted numbers have been on the decrease since the early 90s (when shuttle production ramped down) they are still a little higher than they were in the 70s.

I'd love to see NASA's budget increased, but not now - it would just get funneled into dead-end pork projects like SLS. I'd much rather wait till Starship is successfully operating (New Glenn would be a plus), and it is political viable to end the SLS entirely, and redirect all that money and some into missions (both science and exploration) rather than hardware development.

Or to put it another way, it isn't worth it to me to spend 1960's era money if we are only going to get 1960's era results. If we ever want to move on to bigger things in space, like colonization, we can't just throw money at the problem, we need to find ways to bring the cost down first.

Re: Voyager 2 is back online after eight months of radio silence

#84
post #32

Lets imagine... hypothetically [1] that we could design a new kind of space oriented machines, sort of a "spatial server" or a "telephone repeater", that could be left in Pluto (or an asteroid, or orbiting Saturn, whatever...), and be designed to take this weak signals, amplify it, and resend it to the earth Would this help to increase the range of what discover can report and... hum, discover? Would help us to have…

Its useless. Most of the time Earth is closer to the Voyager spacecraft than Pluto (or Saturn or...) is! In addition, we can build and maintain much better equipment here on Earth than we can ship to Pluto.

If you wanted to do this "for real", the better option is to send a train of repeaters after the Voyager spacecraft in roughly the same flightpath. More effective, and vastly easier.

Re: Voyager 2 is back online after eight months of radio silence

#85
post #4
post #3

I was just reading the pale blue dot and he mentions that Voyager 2’s scan platform jammed after its encounter with Saturn. Voyager 2 emerged from behind Saturn (as seen from the Earth) in August 1981. The scan platform had been moving feverishly—pointing here and there among the rings, moons, and the planet itself during the all-too-brief moments of close approach. Suddenly, the platform jammed. A stuck scan platfor…

Our hacks are nothing compared to the hacks of these old school nasa programmers :) The amazing thing (to me) is that they developed the Voyager spacecraft in an era when space flight wasn't hugely popular and the budgets at NASA were being cut regularly. NASA went from a peak of $6bn a year in the mid-sixties under Johnson to almost half that under Ford and Nixon. The engineers were well-respected and they clearly f…

You can't just look at the NASA budget. Defense spending was also a huge part of our activities in space.

My grandfather built satellites at Lockheed in Sunnyvale all through the 60s and 70s and it was a glorious time for him. For reasons that I never quite understood, he hated Reagan for "destroying the industry" in the 80s (by which time he was in Denver at MM).

Re: Voyager 2 is back online after eight months of radio silence

#86

Earlier quoted context omitted.

The tech has existed at least theoretically since the 60s but nobody is willing to use it. https://en.m.wikipedia.org/wiki/Project_Orion_(nuclear_propu...

Check out Hardtack Teak. It was an exo-atmospheric nuclear test above Johnston Atoll. The blast was visible from Honolulu and a large glowing red cloud drifted over the island chain all the way from Johnston Atoll. There are areas of the zone underneath the explosion which are still hot to this day. And that was just one of the tests that went right. There were plenty of failures too, both in atmosphere and on the la…

[deleted]

Re: Voyager 2 is back online after eight months of radio silence

#87
post #64
post #18

Earlier quoted context omitted.

Future Crew - Second Reality

Check out Zarch on the Acorn Archimedes. https://www.youtube.com/watch?v=MNXypBxNGMo It's an awesome 3D game from 1987 (with truly awful sound). That was made 6 years before Second Reality, on a RISC-based computer. It's incredible.

Thats a pretty zippy frame rate there :)

I did recognize the style, and then reading the comments Isaw it was indeed by David “Elite” Braben.

Watch this : https://www.youtube.com/watch?v=3HbsfeubbRA Quite a journey from there to here

Re: Voyager 2 is back online after eight months of radio silence

#88
post #6
post #3

I was just reading the pale blue dot and he mentions that Voyager 2’s scan platform jammed after its encounter with Saturn. Voyager 2 emerged from behind Saturn (as seen from the Earth) in August 1981. The scan platform had been moving feverishly—pointing here and there among the rings, moons, and the planet itself during the all-too-brief moments of close approach. Suddenly, the platform jammed. A stuck scan platfor…

I found out that usually happens when you have some constraints. The more constraints the more clever ways people find to achieve their goal.

and we have found the genesis of corruption.

Re: Voyager 2 is back online after eight months of radio silence

#89

"Which will be just in time for the arrival of the Perseverance Rover on Mars, another mission DSS43 will handle" Wait, so they sent Perserverance on it's way to Mars without comms in the southern hemisphere? Or is this a backup?

The Mars rovers, including Perserverance, usually communicate directly over a high-speed link with one of several relay satellites orbiting Mars. The smaller antennas of the DSN can communicate with the relay satellites as well. Furthermore, the locations of the stations aren't determined by the hemispheres. Everything DSN is used for is far enough away from Earth that it doesn't matter if the antenna is in the north…

While the rotation of the earth is one of the primary reasons for the spacing, the hemisphere does matter for Voyager. From the article: "As Voyager 2 is heading southwards compared to Earth's orbital plane, only a dish south of the equator can send the probe a sufficiently powerful signal."

Re: Voyager 2 is back online after eight months of radio silence

#90

Earlier quoted context omitted.

Interstellar travel, unless there's a revolution in propulsion, is unlikely to happen I think. I'm sure that at some point they'll send up another probe with more fuel to go out faster, but it's not going to be revolutionary.

The tech has existed at least theoretically since the 60s but nobody is willing to use it. https://en.m.wikipedia.org/wiki/Project_Orion_(nuclear_propu...

There is another option that doesn't involve "scary" nuclear.

https://en.wikipedia.org/wiki/Breakthrough_Starshot

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