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Hobbes

 Discussion on question by python_user…

Imported from a comment discussion on workplace.stackexchange....
Hobbes
Aug 11, 2021 07:08
Settings->Location services->your app->allow access to location services->never/only when the app is running. Both options should solve the problem. Are you saying the app circumvents this?
Hobbes
Aug 11, 2021 07:08
I suspect that will make it difficult to get the app accepted in the iOS store.
 

 The Pod Bay

General discussion for space.stackexchange.com. Check our sche...
2
Hobbes
Dec 15, 2019 17:04
So I'm trying something else, for the sake of my sanity: I'm going to be absent for a while. I may return in a few months, but for now I'm done.
Hobbes
Dec 15, 2019 17:01
in case anyone wonders where I've gone: When I first came to this site I found an environment where interesting questions were asked, and I could have fun answering them. For several months now though, the annoyance:enjoyment ratio has been going up, for two reasons. One is a rising number of low-quality questions, the other is a personality incompatibility with another regular user. I've tried getting less involved in things, but that turned out not to be enough.
Hobbes
Jul 5, 2019 12:17
@uhoh You could also add an answer to the linked question instead of reopening this one. Or are you saying the 2 questions require different answers?
Hobbes
Mar 26, 2019 19:39
ah, that's it. A useless order, but an order nonetheless. I'd have preferred ordering by date though.
Hobbes
Mar 26, 2019 18:58
I occasionally browse space.stackexchange.com/questions?sort=unanswered to find Q I can A. The utility of that page is hampered though by the questions being in random order.
Hobbes
Mar 25, 2019 18:44
10^4 questions now.
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Hobbes
Feb 14, 2019 20:15
@PearsonArtPhoto in the inner solar system video, are the Halley's Comet missions missing?
Hobbes
Dec 7, 2018 12:03
Inflatable legs that can support 25 tons weigh in the region of 2.5 tons (based on the weight/payload ratio of a Zodiac boat). Then they have to be inflated (compressor or gas tank) and they have to be fireproof (remember the legs occasionally catch fire during landing). Seems a bit much for a contingency option.
Hobbes
Nov 30, 2018 17:01
I thought Gray Dragon was cancelled?
Hobbes
Nov 30, 2018 14:52
Isn't CLPS mainly a project for a Moon lander? Not a sector SpaceX is active in now, and their engineering plate is quite full already, so not surprising they didn't get a contract.
Hobbes
Nov 29, 2018 15:04
while that's an admirable sentiment, it's also unrealistic. Words have effect on people, that's just how we are wired.
Hobbes
Jun 14, 2018 07:19
@uhoh, it's 'How did NASA prevent third parties spoofing Apollo communications'.
Hobbes
Jun 13, 2018 18:07
there are some alternate endings to the MER strip: https://www.reddit.com/r/xkcd/comments/6or057/xkcd_695_apparently_cern_scientists_couldnt/
https://imgur.com/VbKV9DF and https://i.imgur.com/VZvj5S7.jpg
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Hobbes
Jun 13, 2018 17:18
So, we have another useless question getting into the 'hot network questions' pool and attracting huge numbers of views. On one hand, it's nice that people see Space.SE, on the other hand, does it always have to be the conspiracy-nutter questions that attract the attention?
Hobbes
Jun 10, 2018 17:16
it looks like a 2-step process: the system counts the number of comments per user and raises a flag if a threshold is reached. The moderator can then move the discussion. meta.stackexchange.com/questions/253087/…
Hobbes
Jun 10, 2018 15:35
Normally there's a pop-up after about 12 comments that asks if you want to move the discussion, I wonder why that's not happening here. Too many downvotes?
Hobbes
May 22, 2018 19:18
@uhoh, if you want privacy, you're better off using Firefox plus a bunch of anti-tracking plugins (Noscript, Privacy badger, etc.)
 

 Discussion on answer by Ludo: Does th…

Imported from a comment discussion on space.stackexchange.com/...
Hobbes
Aug 9, 2019 00:46
do you have a reference for "The Voyager spacecraft are not reprogrammed anymore"?
 

 Discussion on answer by gerrit: How c…

Imported from a comment discussion on travel.stackexchange.com...
Hobbes
Jun 28, 2019 08:08
@gerrit you're catching a cold because you're staying somewhere new and are exposed to new strains of cold virus that your immune system hasn't yet adapted to.
 

 Discussion on question by Ryan Morten…

Imported from a comment discussion on aviation.stackexchange.c...
Hobbes
May 26, 2019 09:30
@bogl as I said before, 'free fall' is a common colloquialism for objects dropped in an atmosphere that don't generate significant lift. This includes anvils, bricks, bowling balls and other objects that don't have either wings or a parachute. You comment tries to apply spherical cow physics to the real world.
Hobbes
May 26, 2019 09:30
do LAPES drops count? these use horizontal parachutes to decrease forward speed, but their vertical speed is not limited.
 

 Discussion on answer by Juan Jimenez:…

Imported from a comment discussion on aviation.stackexchange.c...
Hobbes
May 26, 2019 09:29
It glided at a high rate (low L/D ratio).
 

 Discussion on question by uhoh: How m…

Imported from a comment discussion on space.stackexchange.com/...
Hobbes
May 8, 2019 14:07
NASA didn't see a rotation, they saw an oscillation. So an answer would have to be done from first principles, which means working out how much force a runner exerts in a tangential direction by pushing off on each step, and how much of that is cancelled out at the end of each step. This in turn involves aerodynamics of the human body. More biology than space exploration...
 

 Discussion on question by Nick van de…

Imported from a comment discussion on space.stackexchange.com/...
Hobbes
Mar 1, 2019 19:52
what-if.xkcd.com/1
 

 Discussion on answer by UKMonkey: Roc…

Imported from a comment discussion on space.stackexchange.com/...
Hobbes
Jan 10, 2019 12:52
1/2 I W^2 can add up to a lot of energy, but you soon run into material limits: at 60k rpm, a flywheel is close to tearing itself apart. This places an upper limit on how much energy you can store per kg of mass.
Hobbes
Jan 10, 2019 12:52
The S60 KERS is still at the prototype stage, and Volvo has been working on this for decades. Meanwhile, Volvo has battery-based hybrids in series production.
Hobbes
Jan 10, 2019 12:52
This sentence for example needs citation: the fly wheel to be used for power grid storage is efficient because it's lightweight. Quote numbers, and compare with other storage technologies. You can even borrow the data from my answer.
Hobbes
Jan 10, 2019 12:52
@Mazura the Electron is a smallsat launcher from New Zealand. Phrases like "component of the rocket" also indicate launchers are the intended target rather than satellites. OP asks about replacing the batteries (which are used to power the turbopumps on the Electron) with a flywheel.
Hobbes
Jan 10, 2019 12:52
note that the question was about launchers, not satellites, i.e. a lifetime of 10 minutes to 4 hours and no recharging.
Hobbes
Jan 10, 2019 12:52
Flywheels make sense as an addition to batteries, if you have large peaks in supply or demand. And they don't degrade as much with each charge/discharge cycle.
Hobbes
Jan 10, 2019 12:52
And flywheels are anything but lightweight. I've provided numbers, if you know better provide a reference.
Hobbes
Jan 10, 2019 12:52
Name one current satellite that uses flywheels to store energy.
 

 Discussion on answer by asdfex: How w…

Imported from a comment discussion on space.stackexchange.com/...
Hobbes
Jan 8, 2019 20:08
NH has no way to tell how far away it is on its own, but mission control can find out very accurately and upload that information if necessary. But it is not needed. In the 6 hours or so of travel time, the Earth does not move enough to move out of the HGA beam. This question does that math for Voyager. NH is closer, but that 0.6º beam width covers a large portion of Earth's orbit. If Venus were in conjunction with Earth, you could receive NH at Venus.
 

 Discussion between Hobbes and Curious…

Imported from a comment discussion on lifehacks.stackexchange....
Hobbes
Nov 20, 2018 17:20
The second battery common in phones is used to run the clock and maybe keep some memory powered. It does not have enough capacity to run the transmitter.
Hobbes
Nov 20, 2018 14:35
And you only need one of them to make the discovery.
Hobbes
Nov 20, 2018 14:34
Any electronics engineer with some experience in mobile engineering can recognize a battery and transmitter. There are lots of engineers capable of this, and many are incredibly cirious so they'll open any device they buy.
Hobbes
Nov 20, 2018 14:33
" a frequency domain normally not used" - there aren't any. There is a very limited number of frequencies available. You can get scanners for all of them.
Hobbes
Nov 20, 2018 14:07
That would be trivially detectable. Millions of phones are opened up every year, radio scanners etc.
Hobbes
Nov 20, 2018 13:44
It's far easier to hack the phone via software and use the existing microphone and radio than to steal your phone, insert tiny custom circuitry and get you your phone back.
Hobbes
Nov 20, 2018 13:35
Any "methods, to degrade the capacity of the (hypothetical) internal battery" depend on the implementation of that battery. A battery installed for espionage purposes isn't going to be reachable by regular phone applications
Hobbes
Nov 20, 2018 13:03
Any secondary internal battery is going to be obvious to anyone opening the device, so no phone you buy in a shop is going to have one. Espionage agencies may modify the occasional phone for spying on a specific target, but unless you're in that trade or a high-ranking government official, getting your phone swapped out for a rigged one is not a credible threat.
Hobbes
Nov 20, 2018 13:03
A Faraday cage is basic physics, if it doesn't work you haven't built a good one.
Hobbes
Nov 20, 2018 13:03
the correct answer on that question was "No, even with any internal capacitors or small secondary batteries, there isn't enough power to get off even a small amount of transmission. Transmission simply requires too much power, even for relatively short range given the type of transmitter in the phone. "
 

 Discussion on question by Zlelik: Why…

Imported from a comment discussion on space.stackexchange.com/...
Hobbes
Jun 6, 2018 13:12
Helicopter altitude record is 12 km, a long way from space. en.wikipedia.org/wiki/Flight_altitude_record
 

 Discussion between Hobbes and Conelis…

Imported from a comment discussion on space.stackexchange.com/...
Hobbes
Apr 25, 2018 15:57
Yes, basically you need to cancel out all of your orbital speed (Mars' orbital speed around the sun is 24 km/s, which is a gigantic amount for rocket engines).
Hobbes
Apr 25, 2018 13:09
Suitable maybe, but the sun is one of the hardest destinations to reach in the solar system. That would be a very expensive funeral.
Hobbes
Apr 25, 2018 13:07
Depends on the design of the spacesuit and habitat. The room where the spacesuits are donned is generally inside, so microbes from inside the habitat will be on the outside of the spacesuit. There are spacesuits that are designed to avoid this, (they're attached to the outside of the habitat), but even then it's difficult to avoid all contact between inside and outside. It's much easier to e.g. toss the trash out an airlock than to process it entirely inside the habitat.
Hobbes
Apr 25, 2018 13:07
So it's not just corpses you're objecting to, but all manned missions. It'd be almost impossible for a manned mission to avoid contaminating Mars.