
Hubble is back - perlgeek
https://www.nasa.gov/feature/goddard/2018/update-on-the-hubble-space-telescope-safe-mode
======
datahipster
Ha!

They were able to recover the failed backup gyroscope by executing a series of
attitude maneuvers while switching between operational modes on the gyro.

They literally shook the spacecraft and turned the gyro off-and-on.

Sometimes you gotta bang on something to get it to work!

I would love to buy a beer for the mission operations team member who came up
with that idea!

~~~
cf498
[https://en.wiktionary.org/wiki/percussive_maintenance](https://en.wiktionary.org/wiki/percussive_maintenance)
ftw

edit: I have to add, i just found out about the extent of the definition.

>make a malfunctioning device or person work.

~~~
weinzierl
Packing a punch is not only useful to fix things, but often the best way to
get you an answer. Or as my control theory professor used to say:

 _If you want to know how an unknown system reacts, first thing you do is to
hit it hard._

What he meant was that applying the Heaviside function to the inputs of a
system to determine the step response [1] is one of the first things we should
do.

[1]
[https://en.wikipedia.org/wiki/Step_response](https://en.wikipedia.org/wiki/Step_response)

~~~
TeMPOraL
I remember that thinking from control theory classes, but I thought you use a
Dirac delta as a hard shove.

[https://en.wikipedia.org/wiki/Impulse_response](https://en.wikipedia.org/wiki/Impulse_response)

(Actually, our control classes told us to do both to get a basic view of a
system.)

------
SpikeDad
Reading about the specs and the planned degradation of the gyros is a very
interesting exercise in planned reduction of a service.

They know the gyros will eventually give out and they have contingency plans
around what kinds of science they can continue to do even when they're down to
1 gyro.

Very impressive. I'm always discouraged hearing people say NASA is wasting
money and science and that's just not true IMHO.

~~~
HenryBemis
While people may think that this is wasting money, I see that this these teams
gain unieque knowledge and experience on how to resolve issues on "machines
far far away", and if we are ever to explore/move humans to a new planet, you
want THOSE exact teams as 'helpdesk' that use anything and everything to bring
things back to life and operation.

~~~
deevolution
I think its reasonable to assume AI will be able to fix these kinds of
problems in the future. They could run simulations of all the possible
failures and solutions ahead of time or during operation eventually

~~~
Mahn
I think the creativity and imagination required to solve this kind of problems
is not really within current AI reach yet. The ability to take existing ideas
and combine them in unique ways to come up with something new is very
powerful, and not yet easily replicable by AI.

~~~
ben_w
Genetic Algorithms are pretty creative. I think a bigger problem is that we
have no general way to turn “what we want” into a mathematically formalised
goal that an AI can work towards — we can only manage specific cases like “how
many components does this signal generator circuit use” or “make a new face
based on these examples of faces”.

~~~
fyolnish
You can probably train them using dwim

------
ourmandave
From this link...

[http://hubblesite.org/the_telescope/team_hubble/#hubbletime](http://hubblesite.org/the_telescope/team_hubble/#hubbletime)

 _Each year astronomers from dozens of countries vie for precious minutes of
Hubble 's unrivaled view of the cosmos.

A review committee made up of experts from the astronomical community
determines which proposed observations address pressing scientific questions
and make the best use of the telescope's capabilities.

Each year more than 1,000 proposals are reviewed and approximately 200 are
selected, which represents roughly 20,000 individual observations._

I feel bad for all the projects that got delayed. I wonder if they'll be
rescheduled, or have to be resubmitted or are just out of luck.

~~~
ambicapter
Some of them might not actually need Hubble specifically. There are a fair
amount of observation platforms, maybe they can get their work done on another
satellite.

~~~
antognini
Perhaps, but given the competition for Hubble time, if you can get the data
you need from another observatory you're generally better off doing so. For
these competitive observatories you usually need to explain why your project
actually requires those facilities.

------
larkeith
I will never cease to be impressed by the sheer skill and quality of design at
NASA, that allows them to keep missions like Hubble or Opportunity operating
far beyond their planned lifetimes.

~~~
sosorry44
It amazes me that they are still in contact with the voyager probes. NASA does
some amazing stuff.

------
redler
Amazing. It's like they performed the Epley Maneuver on a satellite.

[https://en.wikipedia.org/wiki/Epley_maneuver](https://en.wikipedia.org/wiki/Epley_maneuver)

~~~
TomK32
That reads worse that it actually looks like:
[https://www.youtube.com/watch?v=ZqokxZRbJfw](https://www.youtube.com/watch?v=ZqokxZRbJfw)

------
sidcool
Amazing. HN community disagrees on almost all topics, except something like
this. Best news in the past few weeks. Kudos NASA.

------
jldugger
Didn't the NSA gift NASA two hubble class telescopes with a note along the
lines 'bought a ton on bulk discount and never ending up using these two
before the new model was released'?

~~~
wongarsu
Yes, but it was the NRO (I doubt the NSA owns any telescopes).

NASA has plans to maybe use one of them sometime, but because of how expensive
the James Webb Telescope turned out to be doesn't have money to do anything
with the second.

The wikipedia article gives some more context:
[https://en.wikipedia.org/wiki/2012_National_Reconnaissance_O...](https://en.wikipedia.org/wiki/2012_National_Reconnaissance_Office_space_telescope_donation_to_NASA)

~~~
yellowapple
NASA has gotten out of quite a few pickles by using Earthside clones/spares of
spacecraft to troubleshoot issues with the ones actually in space. Even if
NASA had the money to launch the spare telescope, they'd be wise not to.

------
azurezyq
Interesting read.

On the other hand, I remembered that hubble was manually repaired by
astronauts mutliple times back in the space shuttle era. I'm wondering that,
do we have capabilities to perform in-space non-ISS-kind repairs now? Soyuz
may be able to do in-space rendezvous but cargo space is limited.
Soyuz+Progress composition (may be too complicated)?

~~~
craftyguy
No we no longer have this capability. Soyuz capsules are not really designed
for EVA.

~~~
varjag
You can do EVA with Soyuz
[https://en.wikipedia.org/wiki/Soyuz_5#EVA_details](https://en.wikipedia.org/wiki/Soyuz_5#EVA_details)

However that mission will unlikely be possible for both technical and
political reasons.

~~~
InclinedPlane
Servicing HST with a Soyuz is basically impossible. Hubble is in a higher
altitude orbit in a significantly lower inclination than the launch site for
crewed Soyuz vehicles. To perform the plane change maneuver (of 23 deg.) would
require a delta-V of 1.5 km/s (20% of the orbital velocity at the typical
Soyuz destination altitude). That would require bringing nearly 4 tonnes of
extra propellant onboard the Soyuz, which isn't feasible. Additionally, this
doesn't include the added weight of the docking adapter and Hubble replacement
parts that would need to be brought along.

It's conceivable that a repair mission might be possible with the soon to come
into service US crew capsules (Dragon 2 and Starliner) since the rockets that
launch them have more performance than the Soyuz, but even then it would be a
pretty ambitious mission.

------
datahipster
For those interested in learning the spectacular engineering that went into
the Hubble: [http://a.co/d/4kLahfW](http://a.co/d/4kLahfW)

~~~
reneherse
That's definitely not what I expected to find at the link! Thanks for posting
it. My father was an engineer on the Hubble, Hexagon and other reconnaissance
satellites, and I'm sure he'll get a kick out of this "manual" as a gift.

------
zenmaster10665
"so we just gave it a shake et voilà!"

\- some NASA scientists, probably

------
gdubs
“Last week the operations team commanded Hubble to perform numerous maneuvers,
or turns, and switched the gyro between different operational modes, which
successfully cleared what was believed to be blockage between components
inside the gyro”

And here I am on Earth, barely capable of debugging JavaScript code.

~~~
jrootabega
It's also fun to compare programming to surgery, where they work for hours
straight with no backup on a production system that is actively trying to die.

~~~
elboru
It has always amazed how hard it must be to debug an issue in a human being,
you need to check A, B, and C, but if you check C your human will be scared
since it could indicate your human has cancer, if you check B it will be
expensive since it involves a lot of studies, you can also check with A giving
some medicament but it also is expensive and maybe other people needed more.
So you end up testing all three, but none gave you any feedback, the issue
must be somewhere else, those tests took months and it doesn’t help you had
been testing hundreds of other humans and for each case you must understand
the whole context, so you have to start again, meanwhile your human starts to
think you are not capable since you haven’t fixed his problem so he starts
looking for a “second opinion”.

~~~
jrootabega
Perfect explanation for why for House, M.D. was so entertaining.

------
keithnz
I love that they basically mashed all the buttons till it started working
properly :)

------
Jenz
Yay! Cheers to Hubble!

------
ddingus
Because NASA is awesome.

~~~
ddingus
Well, they are. Yeah, I am a fan. NASA is one of the few all good things from
government.

Government can be better, and I hope we can make it better too.

What else to say? I love a good NASA win, geek, nerd, engineering story.

------
dang
Url changed from
[https://twitter.com/NASAHubble/status/1056189182274625537](https://twitter.com/NASAHubble/status/1056189182274625537),
which points to this.

------
leo_song
1990-?

------
superkuh
Hubble is back but nasa.gov is black. A blank black page. All because their
web devs wanted (or were pushed into using) some crap front-end lib that has
no fall-back for no javascript.

nasa.gov's accessibility is absolutely terrible for a government website.

~~~
PetahNZ
So enable javascript?

