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SpaceX rockets and launches

None of them are looking any further for us to go than mars. Because physics.

Even the craft that has currently gone further than anything else has only recently left our solar system, and has taken nearly 50 years to do so. We, as a species, are stuck here. To think otherwise is pure fantasy.
You are correct, assuming scientific discovery. And technology development stops now. You argue in bad faith. Ignore
 
I’ve been on U75 for 20 years, and have never blocked anyone. But today, rather belatedly, I realised that arguing in good faith with misanthropic, mean-spirited individuals, who are probably dissatisfied with the way their own lives have turned out, and thus wish failure on everyone else, does not improve my life in any way. I think I’ll be using the ignore function more in future.
 
I’ve been on U75 for 20 years, and have never blocked anyone. But today, rather belatedly, I realised that arguing in good faith with misanthropic, mean-spirited individuals, who are probably dissatisfied with the way their own lives have turned out, and thus wish failure on everyone else, does not improve my life in any way. I think I’ll be using the ignore function more in future.
Wow :D
 
You can’t develop your way past the laws of physics. You can dream of warp drives all you like, they’re still nothing but science fiction.
Exactly when did these unchangeable, never-to-be challenged 'laws of physics' come into being?

It's an ill-informed position to take.

What we often call laws of physics are really just consistent mathematical theories that seem to match some parts of nature. This is as true for Newton’s laws of motion as it is for Einstein’s theories of relativity, Schrödinger’s and Dirac’s equations in quantum physics or even string theory. So these aren’t really laws as such, but instead precise and consistent ways of describing the reality we see. This should be obvious from the fact that these laws are not static; they evolve as our empirical knowledge of the universe improves.
I know from my 40 years of experience in working on real-life physical phenomena that the whole idea of an ultimate law based on an equation using just the building blocks and fundamental forces is unworkable and essentially a fantasy.


 
This is such a weird, negative viewpoint when technology is creating things that would have been deemed utterly impossible decades or even years ago.
The tech doesn't matter. We are nowhere near humans travelling the distances required for extensive timeliness to a Base let alone a planet that could sustain humans.
No planet is ready. No planet will be ready for humans. It's not like we don't know what planets will be like beforehand. Scientists know the scarcity of another planet similar to earth. Kepler 425b is 1400 lightyears away...and that's the one planet that scientists believe to be potentially similar to earth.
Humans are not made for speeds faster than light. The only way it could ever happen would be to transfer a human person's consciousness to a machine and send that...like a robotic human.

But that would definitely be the end of us
 
The tech doesn't matter. We are nowhere near humans travelling the distances required for extensive timeliness to a Base let alone a planet that could sustain humans.
No planet is ready. No planet will be ready for humans. It's not like we don't know what planets will be like beforehand. Scientists know the scarcity of another planet similar to earth. Kepler 425b is 1400 lightyears away...and that's the one planet that scientists believe to be potentially similar to earth.
Humans are not made for speeds faster than light. The only way it could ever happen would be to transfer a human person's consciousness to a machine and send that...like a robotic human.

But that would definitely be the end of us
Objects cannot be accelerated to a velocity greater than that of light. That is nothing to do with the limitations of our present technology, it is simply the way that the cosmos is. However, if we could travel near the velocity of light, then a journey that would take 1,400 years according to an Earth observer could take a few years for the space traveller.
 
Objects cannot be accelerated to a velocity greater than that of light. That is nothing to do with the limitations of our present technology, it is simply the way that the cosmos is. However, if we could travel near the velocity of light, then a journey that would take 1,400 years according to an Earth observer could take a few years for the space traveller.
1400 light years ...
1400 light years is actually a distance measure of
1400 x 6 trillion miles....or...
8400 trillion miles...that's
8400,000,000,000,000 miles....or... 8.4e+15 miles.
I don't believe any human would survive at or near the speed of light...let alone anything we could built to carry them which would implode with humans imploding also.

However....
We have just about managed 1% of the speed of light...with a massive amount of energy

If we could travel at 99.99 percent of the speed of light, a craft traveling for one year would come back to a world that had aged more than 70 years in their absence. At 99.99999 percent of the speed of light, for a year more thsn 2000 years, would pass on Earth.

So if we ever get close to travelling at the speed of light ... we can forget catching up with family on earth.
 
Who knows, maybe someday after we're all long dead they'll find some wormholes that could make interstellar travel or backwards time travel or whatever possible, nothing wrong with speculating, what annoys me is the suggestion that colonising other planets could be any kind of solution to problems on Earth - or that getting to Mars is so urgent that the US space program should rely on a Nazi billionaire with good rockets
 
Who knows, maybe someday after we're all long dead they'll find some wormholes that could make interstellar travel or backwards time travel or whatever possible, nothing wrong with speculating, what annoys me is the suggestion that colonising other planets could be any kind of solution to problems on Earth - or that getting to Mars is so urgent that the US space program should rely on a Nazi billionaire with good rockets
Oh, get things sorted and all that for sure. Just look at all the garbage floating around the planet, doesn't exactly fill you with confidence about treating the cosmos with care.

As it stands, the idea of billionaires using space for exploitative rather than explorative means is depressing but predictable.

Humankind needs to make the billionaire class extinct first.
 
Oh, get things sorted and all that for sure. Just look at all the garbage floating around the planet, doesn't exactly fill you with confidence about treating the cosmos with care.

As it stands, the idea of billionaires using space for exploitative rather than explorative means is depressing but predictable.

Humankind needs to make the billionaire class extinct first.

I don't like Elon but he is actually pouring money into space travel efforts and has a strong mindset to push towards a manned mission to Mars....not that Mars is a sensible plan for humans. It's only ever going to be a stepping stone "gas station stopover..." if there ever is interplanetary travel. There's nothing there to sustain long term human life. And it would probably rely on Earth indefinitely for supplies of one type or another.

To be honest...if they ploughed the "Space" funds and military armaments spent by all of the earth into dealing with the serious issues on this planet we could possibly have a better future here on earth.

Also... the "laws of physics" as described as "theoretical", have been, and increasingly are being proven. So the laws of physics as we know them may well expand ...we may make discoveries about energy which may impact speed of travel but the basics will be still there. And humans are too fragile a form to travel at 1400 light years and survive ...physically...
We would have to become machines...with consciousness ...or holograms with a conscious link...which could travel while our physical selves remain on earth.
That may be the only actual physical solution. It still would be shit because our physical selves would die... as the hologram still travels.
 
1400 light years ...
1400 light years is actually a distance measure of
1400 x 6 trillion miles....or...
8400 trillion miles...that's
8400,000,000,000,000 miles....or... 8.4e+15 miles.
I don't believe any human would survive at or near the speed of light...let alone anything we could built to carry them which would implode with humans imploding also.

However....
We have just about managed 1% of the speed of light...with a massive amount of energy

If we could travel at 99.99 percent of the speed of light, a craft traveling for one year would come back to a world that had aged more than 70 years in their absence. At 99.99999 percent of the speed of light, for a year more thsn 2000 years, would pass on Earth.

So if we ever get close to travelling at the speed of light ... we can forget catching up with family on earth.
"We have just about managed 1% of the speed of light...with a massive amount of energy"

Are you sure about that? A spacecraft reached 30,000 kilometres (18,000 miles) per SECOND? When was that?

You cannot tell how fast you are moving, if you are moving at a constant velocity, so a human body would be unaffected by travelling at 99% of the velocity of light. It is the acceleration that you notice. The best thing would be to contrive the acceleration to be one g, so the travellers would feel that they were in normal Earth gravity.
 
"We have just about managed 1% of the speed of light...with a massive amount of energy"

Are you sure about that? A spacecraft reached 30,000 kilometres (18,000 miles) per SECOND? When was that?
I didn't mean a current "spacecraft".. I meant that we have reached 1% already and actually much faster than 1%.
We have made particles travel at extraordinary speeds...up to 99% of the speed of light.

The Parker Solar Probe is I think the fastest spacecraft so far and it traveled at a speed of 635,266 kilometers per hour. Which works out at 10,587 km/minute... 176km/sec..it's definitely only a matter of time and energy before that target is hit. Just not with a human inside it. As you say...g forces would kill us.

Edited thanks to urbanspaceman. Sorry....the brain farted
 
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I didn't mean a current "spacecraft".. I meant that we have reached 1% already and actually much faster than 1%.
We have made particles travel at extraordinary speeds...up to 99% of the speed of light.

The Parker Solar Probe is I think the fastest spacecraft so far and it traveled at a speed of 635,266 kilometers per hour. Which works out at 10,587 km/second....it's not 1% yet but it's definitely only a matter of time and energy before that target is hit. Just not with a human inside it. As you say...g forces would kill us.
Cannot get my head around the speed there!
 
Cannot get my head around the speed there!
That's because it's wrong. Aladdin divided km/h by 60 to get km per minute, but wrote it as km per sec

The correct speed in km/s is a not inconsiderable 176 km/s

Also, there are several comments above suggesting that travelling at some given speed would be dangerous. This is wrong. There are no physiological effects caused by travelling at a given speed. Rapid acceleration however, can be uncomfortable.
 
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That's because it's wrong. Krtek divided km/h by 60 to get km per minute, but wrote it as km per sec

The correct speed in km/s is a not inconsiderable 176 km/s

Also, there are several comments above suggesting that travelling at some given speed would be dangerous. This is wrong. There are no physiological effects caused by travelling at a given speed. Rapid acceleration however, can be uncomfortable.


Thanks.. I've edited my post... my head is fried.

Travelling at speed is ok for humans. And yes..we can tolerate maybe 6g forces . But there's no way yet for humans to survive acceleration to anything like the speed of light..
 
Thanks.. I've edited my post... my head is fried.

Travelling at speed is ok for humans. And yes..we can tolerate maybe 6g forces . But there's no way yet for humans to survive acceleration to anything like the speed of light..
There is no physiological problem with indefinite acceleration, in fact acceleration at 1g would be ideal, and would build up to huge speeds over a relatively short time. In fact, from the - difficult to get your head around - perspective of general relativity, the surface of the Earth is constantly accelerating upwards at 9.8 m/s² = 1g. This acceleration is what we perceive as the force of gravity, which we experience all our lives without ill effects.

I still remember the so-called SUVAT equations from school

v = u + at
s = ut + 0.5at^2
v^2 = u^2 + 2as
s = vt - 0.5at^2
s = 0.5(u + v)t

where

v is the final velocity
u is the initial velocity
a is the acceleration
t is the time taken
s is the distance travelled

So, to accelerate to say 10% of the speed of light at an agreeable 1g would take about a month. I stopped at 10% of c, as relativistic corrections are significant at higher speeds, making the calculations a bit more intricate.

As a practical consideration, there is no existing or foreseeable propulsion method that could reach any higher speeds. The best prospect for 5% to 10% of the speed of light would be massively powerful fusion engines, using vast amounts of deuterium and helium-3 mined from the atmospheres of Uranus and Neptune, to send a relatively small payload.
 
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What never ceases to amaze me about all these ''experts'' proposing to accelerate space vehicles to some enormous velocity to travel to nearby stars is one small but pretty important detail.

In fact I watched a fairly entertaining video a few years ago which explored the scenario of the imminent destruction of Earth (a wayward neutron star, if I recall correctly) which at least gave humanity a few years to prepare. Inevitably the wealthiest (i.e. cunts) had a huge spacecraft assembled in Earth orbit. They decided to propel it using nuclear explosives and a "push plate" and the journey would only take a few tens of years.

Assuming that worked - which it theoretically could - and it arrived at the target star/planet, no-one ever seems to realise you'd still have to slow the spacecraft down again...
 
The reason space probes take so long to get to places like Mars and especially the outer planets is because we slingshot them on a hyperbolic orbit so they loop around the Sun and the inner planets, the further and faster they need to go then the more loops. I believe the Cassini probe did two loops around the Sun and Earth and one each around Venus and Mars to get up to speed. The reason we do this is because we only currently have chemical rockets which give a massive kick when taking off but after that it's coasting. Constant boost ie accelerating through the first half of the journey and decelerating through the second half is a whole different ball game. At Mars current (this moment) distance from Earth, an ion drive vessel capable of 0.01g could make the journey in 44 days and Mars is currently on the other side of the Sun. Ion drives exist now, they are tiny experimental things but the tech is scalable and they violate no physical laws. It's just money and engineering knowhow that is lacking.
A fusion drive ship that could manage 1G throughout its flight could do it in 4 days and 9 hours. Fusion drives are somewhat further off than ion drives but again violate no currently known physical laws. We don't need magical technology like reactionless drives and antigravity to colonise the Solar System we can do it with technology we know is possible but just don't have yet.
As for magical technologies like FTL well the current opinion is that it's impossible but at this point in our ignorance (knowledge really is the wrong word) we really just don't know. Astrophysics is at best a century old and the idea that we now know all we will ever know about the nature of the Universe is just plain daft.
Even now there are plenty of physicists who think there may be ways round the speed of light, try googling the works of Miguel Alcubierre, Matt Visser and Kip Thorne. Perhaps they are right, perhaps they are wrong. Perhaps FTL is easy and perhaps it will remain forever beyond us but to rule it out forever from where we stand now really is a failure of imagination.
 
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