Kinda counterintuitive... Black holes are getting bigger by consuming more matter and packing it more densely and yet are expanding the universe.

Or could this be some sort of invariance or conservation link between spacetime and matter/energy?

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Indeed. The radiation from Jupiter is intense. I think the current spacecraft in orbit around Jupiter (Juno) has its orbits planned to spend as much time as possible outside the radiation belt.

There is a concept to do something along these lines, the Sabre rocket engine. https://en.m.wikipedia.org/wiki/SABRE_(rocket_engine)

Most likely governments will force space companies to do it -> cost will be baked in to launch price -> customers fund it

Great answer, thanks for your time. So even though due to expansion of space-time some galaxies will moving away from us at effectively the speed of light, they won’t be “frozen in time” from our perspective because that increase in distance doesn’t equate to an increase in velocity?

I actually made this argument in a uni paper I wrote recently, Callisto is the only Jupiter of Moon that can be rationally colonised, even sending robotic missions to land on Europa would be insanely difficult due to the radiation belts.

We already won it over 53 years ago. I've heard a lot of talk lately about China's lunar conquest ambitions but wake me up when they actually visit for the first time.

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You might not mean time dilation- since space is expanding it will not change the speed of objects. Like stretching a balloon, two dots will grow apart, but that doesn’t mean they are traveling relative to each other.

Light doesn’t experience time. But what does the expansion mean for observing distant galaxies? I do know that there are some galaxies that we will never be able to see. The expansion of space will happen faster than their light can traverse that distance.

Other galaxies will red shift until they aren’t detectable any more- light may still be reaching us but that frequency of the light as it travels towards us will slow. This is sort of like being in a wave pool and walking backwards. The time between waves grows greater the further away you get from the source.

When we calculate the age of galaxies, we have to consider expansion, and the degree of red shift helps us figure it out. Light that has been traveling since right after the Big Bang may have only been traveling for 13 billion years… But it will have travelled many many more light years in that time.

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I'm aware which is why I used the word "practical". When we have a city of say, a million people getting most of their power from a fusion reactor then I might get chubby about the prospect of us operating a fusion reactor the better part of a billion kilometers from here.

The eject is, they have to account for it when calculating long distances.

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An experimental test was proposed.

Let's see whether the experimental results match the new theory.

Seems like the dataset for the experiment may exist in the cosmic background radiation observations we already have.

I am not an expert. But I think it is mostly just the degree of red shift when moving away from us. This is why we know that.

China is talking about the moon! Quick we need control so now there NEEDS to be rules for the moon which NO ONE CAN CLAIM. Cool man.

Yeah - Callisto is an awful place to do any of that.

The rovers on mars are quite far from olympus mons. Pretty sure it would take a really long time to get there, like years or decades.

It's technically possible to send a new rover to climb that mountain but the scientific justification for that expenditure is lacking.

Landing on an inclined surface is more difficult / dangerous than a nice flat level area, so the risk may also be a problem.

Mars has killed a few probes. Bear in mind that if anything goes wrong with the multimillion dollar rover at any stage it can lead to politicians cutting funding for future exploration.

From my understanding you can imagine space and time sort of like a trampoline. You put a bunch of marbles on the trampoline, they aren’t heavy enough to bend it much so they roll around on their own. You put a bowling ball in the middle, and suddenly all the little marbles are pulled to the bowling ball.

We’re marbles, we don’t bend the fabric much, but we live on a bowling ball that does. Mass causes a distortion in spacetime, that distortion causes the effect we know as gravity.

Do you think a robot can even get there if it wanted to ?

Makes sense thanks for the explanation.

I’m not confused at all. I understand Mons is on Mars. Which is why I asked if any robots have ever been able to get close ups photos of it.

Do not see how this question can’t be asked in Reddit but ok 👍

EDIT: I see I did mention the space shuttle orbiting. I was wrong about that. Whatever it is that is taking the photos of Mons is what I was referring to.

Hey, I wouldn't call it a pipe dream cultivated by scam artists. Mars has appeal purely for the exploration - just like any other planet. Humans will surely set foot on Mercury too if we don't eliminate ourselves sooner. Mars will never be terraformed and terraforming Mars is a terrible idea. But a reasonable sized human settlement for scientific purposes with a decent number of orbital habitats is in the cards. Over time, I expect most people living within Mars SOI will be living in orbit and perhaps going down to the surface to work.