Re: How far is Jupiter?

From	Sylvia Else <sylvia@email.invalid>
Newsgroups	sci.physics, sci.physics.relativity, alt.astronomy, rec.arts.sf.written
Subject	Re: How far is Jupiter?
Date	2019-02-07 12:42 +1100
Message-ID	<gc1gopF4veU1@mid.individual.net> (permalink)
References	<5C59CDCC.244C@ix.netcom.com> <iljj5ehd8ere6sa357ee7nueq9qpc735f1@4ax.com>

Cross-posted to 4 groups.

Show all headers | View raw

On 6/02/2019 5:04 am, Sir Gregory Hall,  Esq. wrote:
> On Tue, 05 Feb 2019 09:54:20 -0800, The Starmaker <starmaker@ix.netcom.com> wrote:
>> https://www.foxnews.com/science/harvard-prof-doesnt-back-down-from-claims-extraterrestrial-spacecraft-tech-is-flying-past-jupiter-orbit
>>
>> i mean, if a flying saucer is near planet jupiter
>> how long will it take to get here on Earth?
>>
>> this week or next week?
>>
>> i'm not sure how you figure these things out...
>>
>> I didn't go to ...Harvard.
> 
> Time-wise, Jupiter is very far. Given that to
> travel from Earth to Jupiter or vice versa, two
> things must be considered. Acceleration and
> declaration.  One thing that can't be left out
> of the equation is how much force can the
> organism or the ship handle. You don't want
> either to get squashed.
> 
> So, realistically, from a human's standpoint,
> it would take years to travel from Jupiter
> to Earth.
> 

Jupiter's orbit averages about 5 AU which is also its average distance 
from Earth.

1 AU is about 150 million kilometers, or 1.5 * 10^11 metres. So 5 AU is 
about 7.5 * 10^11 metres. Call that s.

Suppose the space ship accelerates at 1g (call that 10m/s^s, and let it 
be a) for half the time, and decelerates at 1g for the other half. Let t 
be the time the whole journey.

	s/2 = 1/2 * a * (t/2)^2

	t/2 = sqrt(s/2 / (1/2 * a))

	t/2 = sqrt(s / a)

	t = 2 * sqrt(s / a)

Substituting for the terms, gives t = 2 * sqrt(10^11 / 10), or 2 * 10^5 
seconds, or about 55 hours.

The top speed reached is 10^6 metres per second, or 36 million 
kilometres per hour, so the orbital speeds of Jupiter and the Earth are 
negligible, as are relativistic effects. The course taken would be 
pretty much a straight line.

Zipping about the solar system would be quite practical if we could 
maintain 1g over an entire journey. Only we can't, and there's no 
realistic prospect of being able to do so.

Sylvia.

Thread

How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-05 09:54 -0800
  Re: How far is Jupiter? Steve Dodds <sdodds@nova-optical.com> - 2019-02-05 10:57 -0700
  Re: How far is Jupiter? "Sir Gregory Hall,  Esq." <greghall@yacht_maester.fake> - 2019-02-05 13:04 -0500
    Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-05 23:54 -0800
      Re: How far is Jupiter? "Sir Gregory Hall,  Esq." <greghall@yacht_maester.fake> - 2019-02-06 10:21 -0500
        Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-06 14:55 -0800
          Re: How far is Jupiter? "Sir Gregory Hall,  Esq." <greghall@yacht_maester.fake> - 2019-02-06 18:16 -0500
            Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-06 16:45 -0800
              Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-06 16:56 -0800
            Re: How far is Jupiter? djheydt@kithrup.com (Dorothy J Heydt) - 2019-02-07 02:09 +0000
              Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-06 20:48 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-07 10:13 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-09 15:06 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-10 00:22 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-10 22:29 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-11 10:04 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-11 10:44 -0800
                Re: How far is Jupiter? pnalsing@gmail.com - 2019-02-11 19:29 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-12 09:08 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-14 00:17 -0800
                Re: How far is Jupiter? The Starmaker <starmaker@ix.netcom.com> - 2019-02-12 08:50 -0800
              Re: How far is Jupiter? Serg Io <invvalid@invalid.com> - 2019-02-07 17:09 -0600
                Re: How far is Jupiter? % <persent@gmail.com> - 2019-02-07 16:12 -0700
                Re: How far is Jupiter? benj <benj.fake@gmail.com> - 2019-02-07 22:24 -0500
                Re: How far is Jupiter? Serg Io <invvalid@invalid.com> - 2019-02-08 07:39 -0600
    Re: How far is Jupiter? Sylvia Else <sylvia@email.invalid> - 2019-02-07 12:42 +1100
      Re: How far is Jupiter? Serg Io <invvalid@invalid.com> - 2019-02-07 12:49 -0600
        Re: How far is Jupiter? benj <benj.fake@gmail.com> - 2019-02-07 17:53 -0500
          Re: How far is Jupiter? Serg Io <invvalid@invalid.com> - 2019-02-07 17:07 -0600
          Re: How far is Jupiter? Sylvia Else <sylvia@email.invalid> - 2019-02-08 16:52 +1100
            Re: How far is Jupiter? benj <benj.fake@gmail.com> - 2019-02-08 13:00 -0500
              Re: How far is Jupiter? Sylvia Else <sylvia@email.invalid> - 2019-02-09 11:22 +1100
          Re: How far is Jupiter? "Chris M. Thomasson" <invalid_chris_thomasson_invalid@invalid.com> - 2019-02-07 22:08 -0800
            Re: How far is Jupiter? Serg Io <invvalid@invalid.com> - 2019-02-08 07:46 -0600
  Re: How far is Jupiter? sam.wormley@gmail.com - 2019-02-05 10:52 -0800
    Re: How far is Jupiter? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2019-02-05 19:57 +0100
      Re: How far is Jupiter? Serg Io <invvalid@invalid.com> - 2019-02-05 14:03 -0600
        Re: How far is Jupiter? "Sir Gregory Hall,  Esq." <greghall@yacht_maester.fake> - 2019-02-05 17:42 -0500
          Re: How far is Jupiter? % <persent@gmail.com> - 2019-02-05 15:51 -0700
          Re: How far is Jupiter? Serg Io <invvalid@invalid.com> - 2019-02-05 17:30 -0600
        Re: How far is Jupiter? Mahipal <mahipal7638@gmail.com> - 2019-02-05 14:52 -0800
  Re: How far is Jupiter? "Bast" <fakename@nomail.invalid> - 2019-02-05 15:08 -0500
  Re: How far is Jupiter? Whisper <beaver999@ozemail.com> - 2019-02-06 14:05 +1100
    Re: How far is Jupiter? "Sir Gregory Hall,  Esq." <greghall@yacht_maester.fake> - 2019-02-06 10:23 -0500
      Re: How far is Jupiter? Whisper <beaver999@ozemail.com> - 2019-02-07 09:34 +1100
        Re: How far is Jupiter? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2019-02-07 00:54 +0100
  Re: How far is Jupiter? mitchrae3323@gmail.com - 2019-02-09 18:46 -0800

csiph-web