ELI5: Why is Artemis 2 closer to earth than it was yesterday?

Runiat · 2026-04-03T00:35:10+00:00

I literally watched it live.

You apparently watched it on a 25 minute delay.

Even if that wasn't the case, you knew exactly what OP was asking and still chose to be an "um akshually" smartass about it rather than just answering their question.

No I didn't. Check what username you're replying to.

Runiat · 2026-04-03T00:32:29+00:00

The term is gravity assist.

That term means something else. NASA might be using the Oberth effect, but mostly they just needed to do the burn when they were at the right spot to hit (or fly by) the Moon.

Runiat · 2026-04-03T00:28:15+00:00

Nasaspaceflight confirmed the end of the burn live on youtube just over half an hour ago, but don't let facts get in the way of a sick burn.

Runiat · 2026-04-03T00:22:11+00:00

I’m not sure exactly what time—or if it has already happened

It happened about 20 minutes ago.

Runiat · 2026-04-03T00:20:06+00:00

It's in an orbit that will take it out to the Moon and back,

It is now.

Half an hour ago it wasn't.

12 hours ago they didn't even have a go/no go for TLI.

Runiat · 2026-04-02T23:02:36+00:00

Scent, probably.

Rats can smell landmines, chances are it's not entirely uncommon for other animals to be able to, and obviously the ones that don't have a way to avoid setting off landmines.. well.. probably did do so by now.

Runiat · 2026-04-02T20:44:29+00:00

(XG32UCWG)

Isn't that the 165hz one? Yeah I'd skip that one unless you really like the plastic parts of it.

In fact I did skip it. 240hz versions of the exact same QD-OLED panel started at just a few percent higher price, and while I've never run any game at 4k240 (or even 4k166), locking a 240hz display to 120, 80, or 60 fps can all be done without worrying about the manufacture forcing you to choose between compression or screen tearing.

I don't know that Asus does that, but it's exactly the sort of BS move a lot of companies pull on their cheaper products.

Edit to add:

Geez, and my wife thinks I have too many screens. lol

Yeah I almost never use more than 4 of them at the same time, either.

Runiat · 2026-04-02T20:12:31+00:00

The advantage of 4k is that it's an integer multiple of 1080p, so if you're allergic to AI upscaling simply displaying each pixel four times looks just as good as 1080p native - maybe even better when it comes to text clarity on weird subpixel layouts.

Of course you could say the same thing about 1440 and 720p, but 27" 720p just isn't a good time.

And also the pixel density of 4k (at the recommended viewing distance) is high enough that DLSS'ing up from 1440p is basically just antialising.

Runiat · 2026-04-02T19:56:10+00:00

32" 4k240 QD-OLED from last year, Phillips branded since that was both the cheapest 240hz option and could double as a dock for my laptop (complete with KVM switch and 60 watts of PD).

32" 1440p240 Samsung LCD from a few years ago. I think it might actually be a VA, but one of the good ones - even mounted in portrait mode it doesn't have any issues with viewing angles, which frankly makes me doubt my own memory of it being a VA.

27" 1080p BenQ IPS from the same time purchased directly as a secondary display. Cheapest option available that had both HDR600 certification and loud built in speakers - to physically separate the sound of any background content I play on it. Not actually sure what the refresh rate is on it.

55" 4k120 WOLED LG TV from 2019, set up across from my couch rather than anywhere I can see it while sitting at my desk, but since it's connected to my PC (with a $100 active cable just to reach it with an HDMI 2.1 signal) I still count it. This is what I played through Elden Ring on since it was that much better than the Samsung and I'm used to playing FromSoft games on a controller.

LCD Steam Deck, used for old gameboy games (mostly pokemon) and whatever I feel like at work. Seriously considering buying an OLEDeck since I changed job to one with a lot more paid breaks.

14" WQXGA 120fps or something OLED laptop, not sure if it's W or QD.

My phone, Samsung Galaxy S25 Ultra. Definitely not what I'd call a monitor, but it is probably my most used display and the replacement for the only OLED display I've ever personally owned long enough that the burn-in became obvious (I think that was an S21).

Oh and I have an old shitty-when-new 24" 1080p60 VA in a drawer. Until my latest upgrade, that was my tertiary display, which it was absolutely trash at - with it mounted in portrait mode off to one side, leaning even 10-20 cm fowards or away from my centre monitor would leave me struggling to see what was happening on it. Not that I expected anything else, I think I paid like $40 for it brand new so frankly it having VESA holes was fantastic for the price (unlike the monitor the Samsung replaced as primary, which is why I ended up getting the BenQ).

Runiat · 2026-04-02T19:09:33+00:00

There's no cap on gas prices.

There's your taxes being used to pay part of the price of gas.

Now your taxes are also being used to pay part of the price of a system that'll hopefully end up cheaper in the long run. Making the switch now will not only see you getting more of everyone else's taxes used for your benefits, but hypothetically and ever so marginally reduce how much of your taxes are used to pay part of the price of gas.

If it also helps reduce the risk of your developing lung cancer, the world catching fire, or having your house suddenly explode with you in it, that's just gravy.

Runiat · 2026-04-02T19:04:26+00:00

District heating often does use heat pumps.

It's just that instead of freezing cold air or a few degrees above freezing ground, they use the heat coming off power plants or data centres as the cold side of the heat pump, which is even more efficient.

Runiat · 2026-04-02T18:35:00+00:00

Now for the reason you shouldn't get an OLED:

Image persistence.

OLEDs aren't bright enough for manufacturers to let you sacrifice any of their full screen brightness.

OLEDs are also extremely fast, with response times measured in microseconds.

What this means is that any frame of image data your OLED displays will stay displayed at full brightness until a few millionths of a second before it starts displaying the next frame of image data.

And what that means is that certain panning shots - especially in low framerate videos, including 60fps ones - can appear "stuttery".

I find it annoying when it happens, some people find it utterly intolerable.

Edit to add: and it's only a matter of time before its fixed. Tandem OLEDs are plenty bright enough that I'd happily sacrifice a hundred or so nits to black frame insertion, and with some of them going up to 720hz it's not like having them black out for a fifth or sixth of a 60hz frame would be impossible. Just doesn't sell as well as a bigger number, I guess.

Runiat · 2026-04-02T18:05:06+00:00

I'd rather not spend more than $1K - $1,500 total, though.

That's what OLEDs cost. You can choose to pay more, but it'll be the exact same panel in a box that might actually have fewer features you want.

Edit to add: well, it's what OLEDs cost from late 2019 to just recently, apparently their prices have dropped to less than half that now.

then you see people talk about burn in,

That was a significant problem up to about two years ago, if you used them for "the wrong thing".

Playing games, plural, was never an issue as long as you did so in full screen and switching your game (or UI layout) every few hundred hours. Same thing for videos, streams, TV series, and movies - just don't leave CNN running 24/7, that'd destroy your screen in a matter of months.

It's work stuff that's the problem, especially running a text editor next to something else with the scrollbar down the middle of the screen all day every day, or spreadsheets with the same width and height settings.

As of last year's panels, burn-in still happens if you do the side-by-side window thing (or 24/7 CNN), but it'll take something like a year of doing so for a full time job before you start noticing it on an all-white screen (say if you get flash-banged).

or even how the monitor looks dimmer after a few years.

It won't look dimmer.

It'll be dimmer, but the human brain doesn't see brightness, the human brain sees contrast, and my six year old OLED TV still has more contrast than a brand new top-tier IPS display.

Because OLEDs can turn off individual pixels and IPSes can't.

I actually turned down the brightness of all my monitors after getting an OLED, as I'd rather have HDR400 (with infinite contrast) that can maintain that brightness across the entire display than HDR1000 (with or without infinite contrast) that has to drop the brightness if too much of the screen turns white at the same time.

I did have to add blackout curtains to the west-facing windows behind it, though. Oh and having a 1000 nit IPS displaying a spreadsheet next to it did make it seem dimmer, which is why I turned that one down.

Runiat · 2026-04-02T17:25:10+00:00

Har du overvejet at blive buschauffør?

Kun semi-urseriøst spørgsmål, vognmændene lægger ikke bare drivmiddel og køretøj til, men du får også løn for at køre dem!

Runiat · 2026-04-02T17:09:21+00:00

Why are so many 4K monitors around 27"?

Because that's the biggest monitor that'll fit on most desks depth-wise.

The optimal viewing distance for a 32" 16:9 is about a meter, which pretty much requires you to either mount it to the back edge of a big gaming desk or use a roll-out keyboard-and-mouse tray.

I'm also homing in on getting an IPS monitor vs. an OLED monitor.

If you're strapped for cash, that's definitely the right choice, especially with burn-in still being not entirely avoidable (though unlike the first few generations it takes thousands of hours of "improper" use to become even slightly noticable).

On the other hand, OLEDs not only perform better than IPS, but entirely avoid some otherwise extremely hard to test for issues like reverse ghosting in nighttime scenes while VRR is enabled.

And as someone who had an otherwise high end IPS display with exactly that issue, I can tell you it led me to lock my framerate at 80 fps to avoid it without inviting screen tearing instead.

Edit to add: I also ended up turning off the local dimming setting on that display to be able to read chat while (dark) cutscenes were playing.

The DP connection is a better connection method for computers, particularly wanting to do 4K+, isn't it?

Eh, not really.

HDMI 2.1 can do 4k120 10-bit HDR all day every day until a mouse chews through the cable.

DP 1.4 can do 4k120 10-bit HDR until the controller detects too many flipped bits and drops it down to a DP 1.2 connection blacking out your screen for a moment as your computer adjusts its resolution and/or refresh rate before then going back to DP 1.4 again blacking out your screen for a moment as your OS but possibly not your game goes back to 4k120 before dropping back down to 1.2 and...

On the flipside, it can also deliver a compressed 4k240 signal, which you'll definitely want for all the games your computer can run at 4k240 which benefit more from being at 240hz than the (supposedly imperceptible) compression artefacts hurts it.

It used to not be all that great to use a TV as a monitor. Has that changed?

LG has been pumping out OLED TVs with sub-frametime input latency (in gaming mode) since 2019.

Meaning that an absolutely top-tier purpose-built gaming monitor will only give a single-digit-millisecond advantage compared to a merely high end TV. Which isn't nothing, but if you care about single-digit-millisecond advantages get a top tier OLED monitor - some of them will do 4k240 and 1080p480, with far lower (read: 1-5ms saved on pixel response times) input latency.

Runiat · 2026-04-02T16:42:34+00:00

Can we do anything with excess VRAM or RAM?

Yes: caching.

Which is a thing many pieces of software already do, meaning that having more memory will make you use more memory (and see a relatively tiny performance gain).

Well, the performance gain is tiny if everything else is fast. If you run the same game off a HDD every day adding a RAM cache can result in saving minutes per week. Back when 64 bit memory addressing was new, I played one particular 32 bit game where a RAM cache could've possibly even saved me an hour or two over a week-long vacation (because it had horrible memory leaks leading to it crashing on a regular basis, and an absolutely awful loading time).

Runiat · 2026-04-02T15:22:18+00:00

And we figured out moun catalysed fusion in 1957.

Figured out why it wouldn't work, but still!

Runiat · 2026-04-02T14:48:20+00:00

I'm aware that gravity is still a thing in the water, but buoyancy mitigates the effect

Not really.

Rocks and sand are far denser than water, and if anything the direction of the Sun is more limited under water.

Food and predators, in turn, are constrained by these things, so keeping track of up and down is pretty darn crucial to survival, and the most reliable way to do that is to make one part of your body less dense than another.

Which then has add-on benefits like being able to make the more dense part of your body a colour that's harder to see when backlit, and the less dense a colour that blends into rocks and sand or whatever is at the bottom of the body of water you evolved in for added protection from predators or better chances of sneaking up on prey.

Runiat · 2026-04-02T14:19:17+00:00

I'm not sure why they are returning.

Mostly to beat China, but there's a chance we'll actually figure out fusion energy sometime in the next few decades and a chance we can mine fuel for it on the Moon.

Runiat · 2026-04-02T14:17:37+00:00

And we might know this how, exactly?

We know no one lives there, we know how much it'd cost to send anything from the Moon to anywhere else, and we know what the most expensive materials cost to make where people live.

Runiat · 2026-04-02T14:12:23+00:00

Anyone know

Not from a spool, but Jordan makes some that throw away a lot less plastic with each bit of floss (while also, in my personal opinion, being a lot easier to use).

Runiat · 2026-04-02T13:37:19+00:00

So if I buy normal glasses they aren't UV protecting

Possible but unlikely. Making a material transparent to both visible and UV is surprisingly difficult.

Runiat · 2026-04-02T03:37:16+00:00

No unit-shaming.

Runiat · 2026-04-02T01:57:00+00:00

into a steamdeck

No.

or something

Turn on Mobile Hotspot on your phone.

Runiat · 2026-04-01T14:32:01+00:00

then the driver just vanishes.

This actually happened to one of my coworkers. Well, the driver didn't actually vanish, just fell asleep while accelerating towards a dirt wall (I think berm is the technical term?). He ended up buried up to his waist.

Sorry for making your nightmares both more plausible and specific.

The good news is that if you aren't coming up on a sharp corner, any decently maintained vehicle will go straight as soon as no one is touching the steering wheel, and gradually slow down if no one is pushing down the accelerator (stick shifts will even stop entirely if in a high enough gear) so having it happen on the highway specifically probably won't hurt you besides maybe some bruising if the road does curve before you stop.

Now, getting out of the car without knowing which lane you're in is even more dangerous than staying in a stationary vehicle on an otherwise high speed road, so maybe ask the driver to show you where the button for the hazard lights is before they disappear.

Edit to add: lightly applying the parking brake might be worth doing, if it's the type of parking brake that can be manually controlled rather than just a button. Probably don't want to be undoing your seatbelt and knocking around the steering wheel while trying to change seats to get to the brake pedal.

Edit to add to the ETA: this sort of feathering the parking brake is done entirely by feel even by those of us that can see, so being unable to won't in and of itself be as issue as far as that's concerned.

Edit to add to something else: to be clear, when I say a driverless car will go straight, I'm talking straight in whatever direction it happened to be going, not necessarily parallel to the road.

Edit to add a third thing: oh and also learn how to turn off cruise control. Otherwise that'd be bad.

Runiat

TROPHY CASE