Talk:2079: Alpha Centauri - Revision history

Nitpicking: 2 comments for the price of one.

2022-08-23T00:03:50Z

2 comments for the price of one.

162.158.238.52 at 23:56, 4 December 2018

2018-12-04T23:56:42Z

162.158.91.59: current time to reach Alpha Centauri

2018-12-04T12:35:49Z

current time to reach Alpha Centauri

Nutster: Grammar fix.

2018-12-03T14:06:52Z

Grammar fix.

Nutster: Forgot signature.

2018-12-03T14:06:17Z

Forgot signature.

Nutster: Nuclear power?

2018-12-03T14:05:25Z

Nuclear power?

162.158.92.34 at 12:42, 3 December 2018

2018-12-03T12:42:28Z

172.69.210.52 at 15:46, 2 December 2018

2018-12-02T15:46:23Z

Nutster: What about ion engines?

2018-12-02T10:54:52Z

What about ion engines?

RIIW - Ponder it: Earth a special case?

2018-12-01T19:43:50Z

Earth a special case?

← Older revision		Revision as of 00:03, 23 August 2022
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	How is the rate of acceleration determined in the calculations above? Why not decrease it a bit and let it take longer time but save energy?		How is the rate of acceleration determined in the calculations above? Why not decrease it a bit and let it take longer time but save energy?
		+	:Because the comic says "35 years." [[User:Nitpicking\|Nitpicking]] ([[User talk:Nitpicking\|talk]]) 00:03, 23 August 2022 (UTC)
		+
		+	Why do the calculations assume natural gas as powering Breakthrough Starshot? Seems unlikely to me. [[User:Nitpicking\|Nitpicking]] ([[User talk:Nitpicking\|talk]]) 00:03, 23 August 2022 (UTC)

← Older revision		Revision as of 23:56, 4 December 2018
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	Not sure if I am the only one wanting to know how long it would take now and add it to the article;		Not sure if I am the only one wanting to know how long it would take now and add it to the article;
	Distance to Alpha Centauri system = 4.367ly / fastest current speed 39,897km/h = 1.041 billion hours = 118757 years --[[Special:Contributions/162.158.91.59\|162.158.91.59]] 12:35, 4 December 2018 (UTC)		Distance to Alpha Centauri system = 4.367ly / fastest current speed 39,897km/h = 1.041 billion hours = 118757 years --[[Special:Contributions/162.158.91.59\|162.158.91.59]] 12:35, 4 December 2018 (UTC)
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		+	How is the rate of acceleration determined in the calculations above? Why not decrease it a bit and let it take longer time but save energy?

← Older revision		Revision as of 12:35, 4 December 2018
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	Little do they realize, it's 3 [https://en.wikipedia.org/wiki/Michelin_Guide Michelin stars]. [[Special:Contributions/172.69.210.52\|172.69.210.52]] 15:46, 2 December 2018 (UTC)		Little do they realize, it's 3 [https://en.wikipedia.org/wiki/Michelin_Guide Michelin stars]. [[Special:Contributions/172.69.210.52\|172.69.210.52]] 15:46, 2 December 2018 (UTC)
		+
		+	Not sure if I am the only one wanting to know how long it would take now and add it to the article;
		+	Distance to Alpha Centauri system = 4.367ly / fastest current speed 39,897km/h = 1.041 billion hours = 118757 years --[[Special:Contributions/162.158.91.59\|162.158.91.59]] 12:35, 4 December 2018 (UTC)

@@ Line 39: / Line 39: @@
 While conventional rockets could not carry enough fuel for an accelerating trip, what about ion propulsion?  Low mass ejected at really high speeds for a long time could accelerate the space craft over the entire distance, with a turn-around halfway.  0.0625 g has been achieved by modern ion thrusters.   The question is whether you could still carry enough propellant for 35 years.  [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 10:54, 2 December 2018 (UTC)
 :Ion engines usually use solar panels for their energy. However, in interstellar space, there is very little light so solar panels are not very efficient. They would first have to come up with an alternative power source to circumvent that problem. [[Special:Contributions/162.158.92.34|162.158.92.34]] 12:42, 3 December 2018 (UTC)
-::I was thinking nuclear power, like make what is powering all the probes to the outer planets.  This would just be ''really'' out-there planets.  I would need to compare the power output of, for example, Cassini's reactor to the power needs of the ion drive (as well the needs of the rest of the system during the trip) to see how well that could work. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 14:06, 3 December 2018 (UTC)
+::I was thinking nuclear power, like what is powering all the probes to the outer planets.  This would just be ''really'' out-there planets.  I would need to compare the power output of, for example, Cassini's reactor to the power needs of the ion drive (as well the needs of the rest of the system during the trip) to see how well that could work. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 14:06, 3 December 2018 (UTC)
 Little do they realize, it's 3 [https://en.wikipedia.org/wiki/Michelin_Guide Michelin stars]. [[Special:Contributions/172.69.210.52|172.69.210.52]] 15:46, 2 December 2018 (UTC)

@@ Line 39: / Line 39: @@
 While conventional rockets could not carry enough fuel for an accelerating trip, what about ion propulsion?  Low mass ejected at really high speeds for a long time could accelerate the space craft over the entire distance, with a turn-around halfway.  0.0625 g has been achieved by modern ion thrusters.   The question is whether you could still carry enough propellant for 35 years.  [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 10:54, 2 December 2018 (UTC)
 :Ion engines usually use solar panels for their energy. However, in interstellar space, there is very little light so solar panels are not very efficient. They would first have to come up with an alternative power source to circumvent that problem. [[Special:Contributions/162.158.92.34|162.158.92.34]] 12:42, 3 December 2018 (UTC)
-::I was thinking nuclear power, like make what is powering all the probes to the outer planets.  This would just be ''really'' out-there planets.  I would need to compare the power output of, for example, Cassini's reactor to the power needs of the ion drive (as well the needs of the rest of the system during the trip) to see how well that could work.
+::I was thinking nuclear power, like make what is powering all the probes to the outer planets.  This would just be ''really'' out-there planets.  I would need to compare the power output of, for example, Cassini's reactor to the power needs of the ion drive (as well the needs of the rest of the system during the trip) to see how well that could work. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 14:06, 3 December 2018 (UTC)
 Little do they realize, it's 3 [https://en.wikipedia.org/wiki/Michelin_Guide Michelin stars]. [[Special:Contributions/172.69.210.52|172.69.210.52]] 15:46, 2 December 2018 (UTC)

← Older revision		Revision as of 15:46, 2 December 2018
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	While conventional rockets could not carry enough fuel for an accelerating trip, what about ion propulsion? Low mass ejected at really high speeds for a long time could accelerate the space craft over the entire distance, with a turn-around halfway. 0.0625 g has been achieved by modern ion thrusters. The question is whether you could still carry enough propellant for 35 years. [[User:Nutster\|Nutster]] ([[User talk:Nutster\|talk]]) 10:54, 2 December 2018 (UTC)		While conventional rockets could not carry enough fuel for an accelerating trip, what about ion propulsion? Low mass ejected at really high speeds for a long time could accelerate the space craft over the entire distance, with a turn-around halfway. 0.0625 g has been achieved by modern ion thrusters. The question is whether you could still carry enough propellant for 35 years. [[User:Nutster\|Nutster]] ([[User talk:Nutster\|talk]]) 10:54, 2 December 2018 (UTC)
		+
		+	Little do they realize, it's 3 [https://en.wikipedia.org/wiki/Michelin_Guide Michelin stars]. [[Special:Contributions/172.69.210.52\|172.69.210.52]] 15:46, 2 December 2018 (UTC)

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 . a strong enough magnetic field to prevent the solar wind stripping off a light atmosphere, that prevents the water boiling and being blown away.
 . an abnormally big moon**.
-. proven plate techtonics.
+. proven plate tectonics.
 . macro life.
@@ Line 29: / Line 29: @@
 [[User:RIIW - Ponder it|RIIW - Ponder it]] ([[User talk:RIIW - Ponder it|talk]]) 19:43, 1 December 2018 (UTC)

← Older revision		Revision as of 19:43, 1 December 2018
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	:But if your going to upgrade, go all the way at least. (Definitely not an excuse I use to buy better PC hardware)[[User:Linker\|Linker]] ([[User talk:Linker\|talk]]) 18:49, 30 November 2018 (UTC)		:But if your going to upgrade, go all the way at least. (Definitely not an excuse I use to buy better PC hardware)[[User:Linker\|Linker]] ([[User talk:Linker\|talk]]) 18:49, 30 November 2018 (UTC)
	Check out figure 1 on page 3 of this 2016 study: http://www.ice.csic.es/personal/iribas/Proxima_b/pdf/Proxima_habitability_II.pdf showing how likely the researchers believe there to be oceans on Proxima b. They expect us to be able to determine what's true directly in 10 years when construction of larger telescopes is completed. Most other sources I found in my brief search are very careful to say that we do not know at all whether or not there is water on this nearby exoplanet. [[Special:Contributions/162.158.186.108\|162.158.186.108]]		Check out figure 1 on page 3 of this 2016 study: http://www.ice.csic.es/personal/iribas/Proxima_b/pdf/Proxima_habitability_II.pdf showing how likely the researchers believe there to be oceans on Proxima b. They expect us to be able to determine what's true directly in 10 years when construction of larger telescopes is completed. Most other sources I found in my brief search are very careful to say that we do not know at all whether or not there is water on this nearby exoplanet. [[Special:Contributions/162.158.186.108\|162.158.186.108]]
		+
		+	I (on the basis of no astrophysicists training, just being a Civil Engineer) can't help wondering that of the three planets in the Sun's Goldilocks zone* that only one has...
		+	1. a strong enough magnetic field to prevent the solar wind stripping off a light atmosphere, that prevents the water boiling and being blown away.
		+	2. an abnormally big moon**.
		+	3. proven plate techtonics.
		+	4. macro life.
		+
		+	And so that 2 is crucial to 1 and 3 and 3 is crucial to 4 (including 1 of course)
		+
		+	So why we expect liquid water everywhere is a mystery to me.
		+
		+	YMMV and I reserve the right to be (proved) wrong
		+
		+	*apparently according to various things I have read over the decades
		+	**some believe Mars had a bigger moon (magnetic field and oceans) before it's orbit decayed and it collided.
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		+	[[User:RIIW - Ponder it\|RIIW - Ponder it]] ([[User talk:RIIW - Ponder it\|talk]]) 19:43, 1 December 2018 (UTC)