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Lunar Flyby

nasa.gov

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Re: Lunar Flyby

#161

Post by dogemaster2026 »

jameslk wrote: post #5
ranger207 wrote: post #2

I have to admit, I've been an Artemis hater ($4 billion per launch lol) but the experience of watching people go back around the Moon has been incredibly inspiring, and it proves to me that maybe we can still do hard things

> $4 billion per launch lol The US spends almost that much on net debt interest each day (~$3 billion/day[0]). Not that adding to the debt helps at all, but the old proverb about being penny wise and pound foolish seems relevant 0. https://www.cbo.gov/publication/61951

[flagged]

Re: Lunar Flyby

#162

Post by voidUpdate »

hulitu wrote: post #156

> Lunar Flyby I though they were going _to the moon_, not "flyby". NASA is a pale reminiscent of its former self. Sad.

They're "going to the moon" in the same way that going to the drive-through is "going to mcdonalds". I think NASA is still as good as it was, they just don't have unlimited "beat the soviets" budget anymore

Re: Lunar Flyby

#163

Post by _moof »

SegfaultSeagull wrote: post #47

Can someone ELI5 how it is one side of the moon is never seen on Earth? The moon orbits and also rotates, does it not?

It's because Earth pulls on the bulge in the Moon created by Earth's gravity.

It has to do with the tides. Except in this case it isn't ocean tides - it's lunar tides. Just as the Moon's gravity creates a bulge in Earth's oceans, Earth's gravity creates a bulge in the material that makes up the moon.

If Earth and the Moon didn't rotate, the bulges would "point" directly at the other body. But with rotation, the tidal bulge is a little bit offset in the direction of rotation. And the Moon used to rotate.

That offset creates a torque. Earth's gravity tries to pull the bulge into perfect alignment. Over time this slows the rotation of the moon until it stopped rotating at all.

(Technically the Moon does rotate, but it does so at the same rate that it orbits Earth. So it doesn't rotate from our perspective.)

Re: Lunar Flyby

#164

Post by voidUpdate »

Some of these photos look so "fake". Maybe because of how they are lit or the lack of atmospheric distortion, they don't quite looks real (I'm not disputing that they are authentic, they just look a bit weird)

Re: Lunar Flyby

#165

Post by [deleted] »

grishka wrote: post #138
willis936 wrote: post #50

Earlier quoted context omitted.

The gravitational pull of the moon lifts up the ocean to cause tides. Well the Earth's gravitational pull is so strong on the moon that the heavier side of the moon always faces the Earth. This is called tidal locking. So the only way to ever see the far side of the moon is to go there. Humans have gone there before, but almost always during an Earth "full moon", which means the far side is unlit. We do have full ima…

But why does this not happen to planets themselves in relation to the sun?

[deleted]

Re: Lunar Flyby

#166

Post by geokon »

irickt wrote: post #56

This is the best animation of the trajectory I've seen: https://apod.nasa.gov/apod/ap260406.html

It's interesting that the flights are not timed for when the moon is in the magnetosphere shadow. As far as I could gather it seems they're intentionally exposing astronauts to more radiation to test equipment (maybe with an eye to future Mars missions?). Hard to get hard details from all the press release fluffy

https://www.nesdis.noaa.gov/news/noaas-space-weather-mission...

Re: Lunar Flyby

#167

Post by sgt »

Gagarin1917 wrote: post #103
kube-system wrote: post #76

Earlier quoted context omitted.

I cannot wait until we get 4k video of people walking on the surface, kicking up dust.

The existing 16mm film from Apollo is roughly equivalent to 2K, and you can see dust kicked up pretty nicely!

Where can we see that in high quality? Generally if I look at YouTube it's compressed and poor quality.

Re: Lunar Flyby

#168

Post by pembrook »

PaulDavisThe1st wrote: post #120
Jblx2 wrote: post #16

Earlier quoted context omitted.

>Defense LAPS every other budget category. I suppose it matters how you lump things, but for federal spending: - $678 B, Social Security - $478 B, Medicare - $425 B, Net Interest - $419 B, Health - $412 B, National Defense - $320 B, Income Security - $184 B, Veterans Benefits and Services - $75 B, Education, Training, Employment, and Social Services - $53 B, Transportation - $43 B, Administration of Justice - $15 B,…

Note there would be no veterans benefits and services without a military, so effectively the total for defense is 412 PLUS 184 = $596B, more than anything except SS. Also note that most people consider social security to be an entirely different kind of government spending than anything else in that list.

No, if the US had no military the majority of veterans benefits and services money would still need to be spent (its mostly healthcare) it would just be bucketed under SS and Medicare/Medicaid then.

Also, without a military the US would not be even 1/3rd as wealthy as it is today, given its military created the global order that secured the last 80 years of the global economic system, shipping lanes and USD dominance. You can argue over specific wars/missions being dumb, but to pretend the overall ROI on that dominance enabling 80 years of relatively peaceful global trade hasn’t been positive is to be intellectually dishonest.

The world is currently teetering on a global economic crisis over just ONE shipping lane not being fully open for a few weeks. Read more history and you’ll see this used to be the norm.

Re: Lunar Flyby

#169

Post by lostlogin »

ranger207 wrote: post #2

I have to admit, I've been an Artemis hater ($4 billion per launch lol) but the experience of watching people go back around the Moon has been incredibly inspiring, and it proves to me that maybe we can still do hard things

> $4 billion per launch

If Trump gets his $1.5T military budget, that would be about the military spend per day I think?

Re: Lunar Flyby

#170

Post by _moof »

grishka wrote: post #138
willis936 wrote: post #50

Earlier quoted context omitted.

The gravitational pull of the moon lifts up the ocean to cause tides. Well the Earth's gravitational pull is so strong on the moon that the heavier side of the moon always faces the Earth. This is called tidal locking. So the only way to ever see the far side of the moon is to go there. Humans have gone there before, but almost always during an Earth "full moon", which means the far side is unlit. We do have full ima…

But why does this not happen to planets themselves in relation to the sun?

Moons get tidally locked because they're very close to their planet, so the planet's gravity is by far the strongest influence.

The planets have much more complicated gravitational interactions because in addition to the Sun's gravity, they influence each other. So you end up with things like orbital resonances instead.

A planet that's close to its star and far from other strong gravitational influences will tidally lock to the star.

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