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NASA releases Hubble image taken in new pointing mode

science.nasa.gov

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Re: NASA releases Hubble image taken in new pointing mode

#91

Post by Rebelgecko »

SaberTail wrote: post #49
cubefox wrote: post #41

Earlier quoted context omitted.

So there are two different technologies that are both called "gyroscope"? One a sensor detecting rotation, the other an actuator inducing rotation?

No, the comment you're replying to is confused. These gyroscopes are entirely used for determining Hubble's orientation. Reaction wheels effect the actual rotation, and Hubble's are fine. I think the confusion is a result of imprecise language talking about how they are used to slew the telescope. They are "used" but as feedback, in conjunction with other systems. Also, there have some prominent reaction wheels failu…

FWIW I think 2 of the Hubble's 4 reaction wheels are dead, which also requires some interesting workarounds

Re: NASA releases Hubble image taken in new pointing mode

#92

Post by codexb »

It's pictures like this that seem to make Dark Matter not all that mysterious. It's clear that the galaxy is surrounded by a lot of dust, and you can clearly see that even as you extend outward and the light drops off, there is still a lot of dust that is just not illuminated.

Re: NASA releases Hubble image taken in new pointing mode

#93

Post by zootboy »

barbegal wrote: post #44

There's a technical description of how the one gyro control system here https://ntrs.nasa.gov/api/citations/20080023344/downloads/20... Essentially using other sensors (star tracker and magnetometer) and kalman filtering for sensor fusion.

Very cool that they were developing the one-gyro control mode all the way back in 2004, and had in-flight tested it by 2008. Seems like they were well prepared for this eventuality.

Re: NASA releases Hubble image taken in new pointing mode

#94

Post by Laremere »

codexb wrote: post #92

It's pictures like this that seem to make Dark Matter not all that mysterious. It's clear that the galaxy is surrounded by a lot of dust, and you can clearly see that even as you extend outward and the light drops off, there is still a lot of dust that is just not illuminated.

Dust that isn't in light is accounted for, and is a different thing from non-baryonic dark matter.

See: https://en.m.wikipedia.org/wiki/Baryonic_dark_matter

Re: NASA releases Hubble image taken in new pointing mode

#95

Post by wongarsu »

el_toast wrote: post #79
FactolSarin wrote: post #71

Earlier quoted context omitted.

I don't think NASA would have chosen the SLS platform though. It was basically mandated by Congress.

Same story with shuttle and that's why it looks the way it is and was as expensive as it was. It would have been a completely different vehicle if Congress weren't meddling.

What NASA wanted was a space station, a small tug to move stuff in space, and a small shuttle to move people and cargo from earth to that station.

The whole point of the space shuttle was to have it service the space station, but the station wasn't greenlit. Instead we got a much bigger shuttle that was useful as a military asset but was a money pit with terrible safety record. Luckily the Soviet Union collapsed and the ISS was funded as a job program for Soviet rocket scientists (out of fear they could be poached to work on ICBMs for other nations).

Re: NASA releases Hubble image taken in new pointing mode

#96

Post by eggy »

dingnuts wrote: post #82
el_toast wrote: post #79

Earlier quoted context omitted.

Same story with shuttle and that's why it looks the way it is and was as expensive as it was. It would have been a completely different vehicle if Congress weren't meddling.

Congress is the owner. Want a different management ideology? Get different management. NASA is wasteful, eh? Maybe that's because they have no incentive not to be wasteful..

NASA is neither a public or private company, but rather a government agency. Congress is an employee of the US taxpayer. I think that makes them more of a manager of NASA and we should hold Congress accountable.

Re: NASA releases Hubble image taken in new pointing mode

#97

Post by alistairSH »

zamadatix wrote: post #76
semi-extrinsic wrote: post #64

Earlier quoted context omitted.

> NASA looks efficient because you’re comparing it to the rest of government. NASA also looks quite efficient when you compare it to many tech companies. NASA has 18k employees and $25bn budget in 2023, let's compare it with some companies: Spotify and Stripe are each equal to half of NASA both in terms of employees and budget. Snapchat and Airbnb are both approx 1/3rd of NASA in both employees and budget. Yahoo has…

How do I read this employees/budget metric to properly rank efficiency? Is 1,000 employees each with an average burn rate per employee of a $1,000,000/y supposed to be more or less efficient than 2,000 employees with an average burn rate per employee of $500,000/y? If so, why is that a sign of an inherently more efficient company when we haven't even mentioned things like output yet? E.g. some of the companies in the…

I think the point was these massive ad companies have similar resources as NASA and don't do anything particularly useful* for society.

* For some definitions of useful

Re: NASA releases Hubble image taken in new pointing mode

#98

Post by eggy »

tempnow987 wrote: post #69
tonetegeatinst wrote: post #7

NASA has such a tiny budget in comparison to other stuff....so they really have to stretch that money as far as they can, and especially considering spacecraft....its a very unforgiving production environment. Am I making a joke about deploying in production? Yes, yes I am. But I also know NASA really does the best they can and I am amazed at the insane work and effort that they do to make sure spacecraft they send a…

Except you look at what they are spending on the entire SLS infrastructure vs what they are getting (vs other science options and/or space exploration options) and basically your mind is blown at how wasteful NASA is. SLS is a $2-$3 billion per launch DISPOSABLE rocket. The orion capsule is going to be something like $20 billion(!). I think things like launch abort and service module with all the propulsion etc are a…

I think a matching industry company, but not necessarily a better counter example, would be SpaceX vs. NASA, for better or worse, and obvious reasons. They are trying to change the launch-and-trash model to reuse, so this requires a paradigm shift. When NASA chose SpaceX and Boeing to compete in 2014, SpaceX won, and after seeing Boeing's current fiasco decline, that's a good thing.

I was a member of the L5 Society [1] in the 80s where we would meet on the Intrepid aircraft carrier in Manhattan to discuss all things space and space colonization (L5 being the Lagrangian point in the Earth-Moon system to place space habitats 60-degrees behind or ahead of the Moon's orbit for stable gravitational equilibrium to minimize fuel or energy to maintain that position). L5 later merged with the National Space Institute under the National Space Society (NSI was Werner von Braun's baby).

I had read O'Neill's 1974 article, "The Colonization of Space" when I was 10, in Physics Today that got me hooked before L5. I bought a Commodore PET 2001 in 1977/78 and was writing a program to show the on orbital plane view of Jupiter's 4 major moons - Io, Ganymede, Callisto, and Europa to better identify which was which when using my binoculars at night. I left L5 in 1988/89. Good times at the Galaxy Diner after the monthly meetings on the Intrepid.

I stopped devoting time to space around then and didn't pick up an avid interest again until SpaceX, even though I had done some machining work for some models of subassemblies for the Spirit and Opportunity Mars rovers in the early 2000s. I am now back at making machines and dreaming of space again!

  [1] https://en.wikipedia.org/wiki/L5_Society

Re: NASA releases Hubble image taken in new pointing mode

#99

Post by hagbard_c »

Hey SpaceX, here's an idea: put a few of your 'Atlas' robots on one of the upcoming Starship test vehicles - maybe the one where you plan to test in-orbit refuelling since it probably takes a bit of extra fuel to get to Hubble's orbit - and get the thing to meet up with Hubble. Have the robots replace the failed gyros, replace the batteries and whatever other consumables that old relic contains. Have them take back the old parts in Starship so they can be studied. The result would be revived Hubble as well as one of the biggest PR coups imaginable. Or, maybe, one of the biggest hits against human space flight if it turns out robots can do the job well enough not to have to send up their meat-based masters, take your pick.

Re: NASA releases Hubble image taken in new pointing mode

#100

Post by toomuchtodo »

hagbard_c wrote: post #99

Hey SpaceX, here's an idea: put a few of your 'Atlas' robots on one of the upcoming Starship test vehicles - maybe the one where you plan to test in-orbit refuelling since it probably takes a bit of extra fuel to get to Hubble's orbit - and get the thing to meet up with Hubble. Have the robots replace the failed gyros, replace the batteries and whatever other consumables that old relic contains. Have them take back t…

Would Hubble fit in Starship for a return flight to ground? Would look nice hanging in the Smithsonian. Flight proven space observatory.
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