In Star Trek: Generations, Dr. Tolian Soran shoots a solar probe into the nearest star in order to

shift the Nexus.

So, if the star is approximately the same distance away from Earth, how fast would the probe actually have to be travelling to reach the star in the allotted time and is there any indication what allowed this speed to be reached?

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    What’s your question? The headline and the body are asking two completely different questions (and one of them is a basic astronomy question with no science fictional input needed).
    – Mike Scott
    Commented Jun 28, 2018 at 11:59
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    “if the star is approximately the same distance away from Earth” — have we got any reason to think that it is? Commented Jun 28, 2018 at 12:04
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    I think we can chalk the event, and its aftermath, up to "bad movie physics".
    – Helbent IV
    Commented Jun 28, 2018 at 12:08
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    Zeiss, it's a star! If they were as close as the moon is to the earth, they would indeed be dead. Commented Jun 28, 2018 at 12:14
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    One fan theory is that everything from when Picard first arrives on the planet is his heatstroke-induced delusion and none of it ever happened ;)
    – Muzer
    Commented Jun 28, 2018 at 14:06

3 Answers 3


The relevant scene described by the OP takes place at the Veridian system. According to the Star Trek: Star Charts (p. 65):

Veridian was classified as a G-class star.

All G-type stars have a mass of 0.84 to 1.15 solar masses and surface temperature of between 5,300 and 6,000 K, so we can safely assume that Veridian is roughly similar in mass and temperature to our Sun. Therefore, any habitable planets will be at a distance of roughly one astronomical unit (AU) or so, which corresponds to the "Goldilocks zone".

Then, assuming the distance from the planet to its star to be around 1AU, the probe should be travelling at warp ~3 in order to hit the star in around 10 secs.

The reason for this is that 1AU is ~8 light minutes or ~480 light seconds, so for the probe to cover the distance in say 10 secs it has to be travelling at a speed of 48c (c=speed of light). According to the wiki and the warp diagram from the TNG Technical Manual seen below, 48c is about warp 3.

enter image description here

Since Starfleet's Class 8 probes can reach warp 9 and are no bigger than a photon torpedo, it is certainly plausible for a small probe like the one used by Soren to reach warp 3 given the available tech at the time.

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    Warp speeds seem to have no consistency in the ST universe, but a fair answer nonetheless. Commented Jun 28, 2018 at 14:17
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    Most of the stuff about warp factors in the wiki, such as the famous warp diagram, comes from quotes from various episodes and the TNG Technical Manual. The latter was created by Sternbach and Okuda to be a reference guide for the series and is not 100% canon, but it's as close we can get.
    – Hans Olo
    Commented Jun 28, 2018 at 14:36
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    It would have to clear the atmosphere first (first 100km or so) I guess and then go to warp.
    – Hans Olo
    Commented Jun 28, 2018 at 14:44
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    @By137 Starfleet's Class 8 probes can reach warp 9 and are no bigger than a photon torpedo, so Soren's probe reaching warp 3 is plausible. I've added this in the answer along with sources.
    – Hans Olo
    Commented Jun 28, 2018 at 17:05
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    @AzorAhai According to the TNG Manual, photon torpedoes can travel at warp if they are launched while at warp, otherwise when launched at sublight they move at high impulse. In other words they do not cross the warp barrier. Hence, I think the probe is a better example ;-)
    – Hans Olo
    Commented Jun 28, 2018 at 17:34

Assuming a similar distance from planet to star as that of Earth, eight light minutes, then the missile had to travel at approximately 50 times light-speed to arrive at the star in ten seconds. That is very much within the realms of Star Trek technology.

More importantly, though, the missile traveled at the speed of plot. Had this been a more suspense-driven plot element, or one the Enterprise crew were intended to have a reasonable opportunity to stop, the same missile fired from the same planet might have take half an hour or more to make the same trip.


It has to be traveling backwards in time.

It's a life sustaining planet in orbit around a star that's between white and yellow in color. This puts light-delay from the star surface to the planet somewhere around 6-9 minutes. We see the effect of the probe on the star from the planet's surface in ten seconds.

It took effect ten seconds after launch. Dude, Warp 10's not enough! It's gotta get there at least 6 minutes before it was launched. Ordinary speed definitions don't really apply anymore. And due to the limitations for how time travel works in Star Trek you've got a serious problem.

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    Can you offer any evidence to back up this bold statement?
    – Valorum
    Commented Jun 29, 2018 at 16:12
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    @Valorum: I fail to understand why high school physics doesn't suffice. Sun-like star -> life zone 6-9 light minutes away from star -> 6-9 minutes to notice the star isn't giving off daylight anymore. But the planet darkens in 10 seconds on screen.
    – Joshua
    Commented Jun 29, 2018 at 16:17
  • Actually we know from the new Star Trek films that the shockwave from an exploding star can travel at warp speeds
    – Valorum
    Commented Jun 29, 2018 at 16:21
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    @Valorum: In which case an observer on the surface would see the shockwave only after it passed while seeing the star on the surface for the next 8 or so minutes.
    – Joshua
    Commented Jun 29, 2018 at 16:23

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