Recent comments in /f/space

Postnificent t1_jd93k29 wrote

Reply to comment by Majestic_Pitch_1803 in Couldn’t we land on an asteroid that is passing through our solar system and use that as a vessel for interstellar travel? by [deleted]

So catch up with the asteroid then speed it up? What’s the benefit? Mining it? Now you are describing a space mining venture not a means of transportation. I thought you were trying to use the velocity of the asteroid to travel. The only way to slow down in space is reverse propulsion or impact. Speeding up is rather simple, expell propellant. Your idea is just a mining operation. (We probably already do this, I don’t trust the news anymore than old Mother Hubbard)

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danielravennest t1_jd90e6s wrote

Reply to comment by The_Solar_Oracle in A New Mission Will Search for Habitable Planets at Alpha Centauri by Aeromarine_eng

In particular, the Sun is a gravitational lens. If you travel about 800 AU in the opposite direction from Alpha Centauri, you can look back and see what is there in great detail, because the lens is 2 million km in diameter. One reason to be that far out is to make it easy to block out the Sun itself, including prominances and the solar corona.

Centauri is 276,000 AU, so using the Sun is a lot easier mission.

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Taxington t1_jd90dib wrote

Reply to comment by tickleMyBigPoop in The SpaceX steamroller has shifted into a higher gear this year by returnofjuju

Your milage may vary by country.

>especially because the price you see online is the price you pay

In most western countries anything els is ilegal.

>Then there's supercharging stations.

EU don't allow that kind of anti consumer behavior all EVs use CCS. No propriety connectors, apple are currently getting fucked over that kind of nonsense.

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danielravennest t1_jd8zgzp wrote

Reply to comment by teehuis in A New Mission Will Search for Habitable Planets at Alpha Centauri by Aeromarine_eng

Current technology is nuclear reactors and electric propulsion. We can feasibly get to 300 km/s with multiple stages. That makes Alpha Centauri 4250 years away.

But due to the "arrival paradox", a trip that long doesn't make sense to try. Assuming technology will keep improving, a later ship with better technology will be faster, and pass the older, slower ship before it arrives. Consider what our technology was like in 2,200 B.C. (4250 years ago).

Only if technology reaches a dead end, or the trips are short enough to not be passed before arrival (perhaps 50-100 years) does it make sense to try.

Our tech is already good enough to travel about 3 times the speed of the Voyagers, and catch up with them about the time their power gets so low we lose contact. If we really wanted to we could do that. We won't, since there are better and closer missions we can do instead.

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thisisinsider OP t1_jd8yzij wrote

Reply to The Northern Lights could dazzle the skies from Washington to New York on Friday, blown by winds from a giant 'hole' on the sun by thisisinsider

TL;DR — from the article:

  • The Northern Lights could appear in the skies over some northern US states on Friday.
  • The lights could be dazzling thanks to solar winds blowing from a giant coronal hole on the sun.
  • The lights — known as aurora borealis — may be seen as far south as Washington and Michigan.
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danielravennest t1_jd8xys1 wrote

Reply to comment by UnknownStrikex in A New Mission Will Search for Habitable Planets at Alpha Centauri by Aeromarine_eng

Yet another method is using the Sun both as a power source, and a gravitational lens to focus the beam on a ship in transit. Starshot is limited by the laser array size. The probe quickly gets too far to maintain beam focus.

So instead you build your laser array near the Sun, where power is plentiful. To start with you aim the beam directly at the vehicle. When it gets too far you switch to a relay mirror at ~800 AU. The Sun bends light by its gravity. In this case it makes a lens with a 2 million km diameter, which gives you astounding resolution.

The beam is used by the ship to power a particle accelerator. The first part of the trip the accelerator is pointed aft to speed up. Later it points the other way to slow down. Going the other way, your communications will be focused back to the relay mirror, so you can get data back.

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Majestic_Pitch_1803 t1_jd8t3ku wrote

Reply to comment by b_a_t_m_4_n in Couldn’t we land on an asteroid that is passing through our solar system and use that as a vessel for interstellar travel? by [deleted]

For sure we are a ways off but perhaps you send smaller rovers that manufacturer these instruments once on board the asteroid, perhaps just deploying enough raw materials to give them a start.

Voyager for example just ran out of gas. As is expected. This is an issue you’d need to solve in such types of travel. Asteroids seem like a possible solution

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