# Question about physics in the movie 2010 **URL:** \ **Category:** Factual Questions\ **Created:** [May 31, 2003, 5:55pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794 "2003-05-31T17:55:55Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Dodeca\_Aww\_Hell\_With\_It](https://avatars.discourse-cdn.com/v4/letter/d/13edae/32.png) [@Dodeca\_Aww\_Hell\_With\_It](https://boards.straightdope.com/u/Dodeca_Aww_Hell_With_It)\ **Post date:** [May 31, 2003, 5:55pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/1 "2003-05-31T17:55:55Z")
I hope this is in the right forum, if not please move. In the movie and book, **2010: Odyssey Two** , the planet Jupiter changes/is changed into a star. But given what I know about star formation and the masses of stars, it seems that it is impossible for Jupiter to turn into a star, unless one decides to completely ignore the laws of physics, which I don’t believe Arthur C. Clarke would consciously do. Also. in the movie, it was made out that Jupiter was shrinking ie; losing mass, which would have made it even more impossible for it to turn into a star. So, what gives? ---
**Author:** ![Patty\_O\_Furniture](https://avatars.discourse-cdn.com/v4/letter/p/96bed5/32.png) [@Patty\_O\_Furniture](https://boards.straightdope.com/u/Patty_O_Furniture)\ **Post date:** [May 31, 2003, 6:12pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/2 "2003-05-31T18:12:58Z")
According to [The Nine Planets](http://seds.lpl.arizona.edu/nineplanets/nineplanets/jupiter.html): > [@](#): > > A star can be larger only because of its internal (nuclear) heat source. (But Jupiter would have to be at least 80 times more massive to become a star.) ---
**Author:** ![Bryan\_Ekers](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bryan_ekers/32/183_2.png) [@Bryan\_Ekers](https://boards.straightdope.com/u/Bryan_Ekers)\ **Post date:** [May 31, 2003, 6:13pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/3 "2003-05-31T18:13:09Z")
My handy-dandy Asimov collection describes a Luyten 726-8 B as a dim red star with a mass of about 40 Jupiters. If Jupiter could somehow be squashed into a Earth-sized sphere, it _might_ acheive fusion and technically become a “star” but it would be a short-lived effect at best, and a faint reddish light at that, not the bright light seen in the movie. If anything, the proto-star Jupiter might be _less_ bright than it is now. ---
**Author:** ![El\_Kabong](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/el_kabong/32/496_2.png) [@El\_Kabong](https://boards.straightdope.com/u/El_Kabong)\ **Post date:** [May 31, 2003, 6:56pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/4 "2003-05-31T18:56:53Z")
> [@](#): > > Also. in the movie, it was made out that Jupiter was shrinking ie; losing mass, which would have made it even more impossible for it to turn into a star. Uh, in the context of the movie, I don’t think there is any reason to assume the shrinking had anything to do with loss of mass. Actually, the whole point was that the existing mass of Jupiter was being compressed to the density necessary for a self-igniting fusion reaction to take place, hence the reduction in volume occupied by the planet. This assumed some sort of ‘magic’ technology on the part of the aliens and, as I recall, the method was not explained in any detail even in the book. OTOH, it seems to me that once the compression process was complete, there would have also to be some artificial means to hold the new sun together continuously, as there wasn’t enough mass there to keep the fusion reaction from blowing the whole thing apart. I’ll leave it for someone better-versed in physics to correct me if this is not the case. ---
**Author:** ![Eegba](https://avatars.discourse-cdn.com/v4/letter/e/7cd45c/32.png) [@Eegba](https://boards.straightdope.com/u/Eegba)\ **Post date:** [May 31, 2003, 7:43pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/5 "2003-05-31T19:43:02Z")
I haven’t read the book since it came out, but IIRC the monoliths were adding mass to Jupiter in order to push it over the edge. Of course that’s a 20 year old memory talking and I may be totally wrong. ---
**Author:** ![Jake4](https://avatars.discourse-cdn.com/v4/letter/j/bc8723/32.png) [@Jake4](https://boards.straightdope.com/u/Jake4)\ **Post date:** [May 31, 2003, 8:00pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/6 "2003-05-31T20:00:30Z")
> [@](#): > > \*Originally posted by Dodeca Aww Hell With It \* > **In the movie and book, 2010: Odyssey Two, the planet Jupiter changes/is changed into a star. But given what I know about star formation and the masses of stars, it seems that it is impossible for Jupiter to turn into a star, unless one decides to completely ignore the laws of physics, which I don’t believe Arthur C. Clarke would consciously do. Also. in the movie, it was made out that Jupiter was shrinking ie; losing mass, which would have made it even more impossible for it to turn into a star.** Arthur C. Clarke is a smart guy; you’re right to give him enough credit not to ignore physics. The scene you’re talking about is at the end when they notice the black spot forming on Jupiter. It grows exponentially larger, and the astronauts discover that the black spot is made up of tons and tons of monoliths (infinitely black, smooth slabs of proportions 1:4:9). It is impossible for Jupiter, as it is now, to turn into a star, because it isn’t massive enough. If it were massive enough, it would have turned into a star long ago. What the monoliths were doing was reproducing, increasing the mass of Jupiter to give it enough mass to form into a star, thereby changing the environment on Europa (one of Jupiter’s 4 largest moons) to accelerate the evolution of the life forms living on that moon. As the monolith reproduction proceeded, the extra mass caused Jupiter to shrink, yes, but decreasing in _size_, not in mass. The extra density allowed Jupiter to begin the stellar fusion reaction, creating Lucifer. ---
**Author:** ![Bryan\_Ekers](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bryan_ekers/32/183_2.png) [@Bryan\_Ekers](https://boards.straightdope.com/u/Bryan_Ekers)\ **Post date:** [May 31, 2003, 8:30pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/7 "2003-05-31T20:30:24Z")
> [@](#): > > \*Originally posted by Jake4 \* > What the monoliths were doing was reproducing, increasing the mass of Jupiter to give it enough mass to form into a star, thereby changing the environment on Europa (one of Jupiter’s 4 largest moons) to accelerate the evolution of the life forms living on that moon. As the monolith reproduction proceeded, the extra mass caused Jupiter to shrink… That kinda begs the questions of where the monoliths’ mass was coming from. I thought it was implied in the movie that the monoliths were being created out of Jupiter’s own mass, since Jupiter was losing color as the monoliths spread, but if this isn’t the case, did the monoliths have some unknown (possibly extradimensional) source? ---
**Author:** ![Dodeca\_Aww\_Hell\_With\_It](https://avatars.discourse-cdn.com/v4/letter/d/13edae/32.png) [@Dodeca\_Aww\_Hell\_With\_It](https://boards.straightdope.com/u/Dodeca_Aww_Hell_With_It)\ **Post date:** [June 1, 2003, 12:02am UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/8 "2003-06-01T00:02:17Z")
> [@](#): > > \*Originally posted by Jake4 \* > \*\*The scene you’re talking about is at the end when they notice the black spot forming on Jupiter. It grows exponentially larger, and the astronauts discover that the black spot is made up of tons and tons of monoliths (infinitely black, smooth slabs of proportions 1:4:9). > > What the monoliths were doing was reproducing, increasing the mass of Jupiter to give it enough mass to form into a star, thereby changing the environment on Europa (one of Jupiter’s 4 largest moons) to accelerate the evolution of the life forms living on that moon. As the monolith reproduction proceeded, the extra mass caused Jupiter to shrink, yes, but decreasing in _size_, not in mass. The extra density allowed Jupiter to begin the stellar fusion reaction, creating Lucifer. \*\* But I recall that it was fairly clear that the monoliths were “sucking” up Jupiters atmosphere, which would mean that mass was simply being transferred from Jupiter to the monoliths and not being increased. ---
**Author:** ![Kilt-wearin\_man](https://avatars.discourse-cdn.com/v4/letter/k/82dd89/32.png) [@Kilt-wearin\_man](https://boards.straightdope.com/u/Kilt-wearin_man)\ **Post date:** [June 2, 2003, 6:02pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/9 "2003-06-02T18:02:53Z")
I always kinda figured the monoliths were adding mass (mysteriously, of course - they _are_ monoliths…) and the increased heat that resulted was changing the atmospheric weather patterns and burning off some of the gasses, leading to the loss of color pre-fusion. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 2, 2003, 6:28pm UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/10 "2003-06-02T18:28:47Z")
Jupiter is just about exactly at such a mass that no matter what you do to it (add mass _or_ remove it), it’ll get smaller. And the simplest explanation for what the Monoliths were doing is that they were adding mass, presumably warped in from elsewhere using that whole hyperspace gate thing they do (or whatever it’s called). Assuming that this is the case, the resulting star would probably been a red dwarf, which would make it rather faint (as stars go) and, well, red. But it would definitely be mighty bright, by the standards of things in the sky: I think brighter than the full Moon, but I’d have to check the numbers. On the other hand, though, it’s probably fair to just describe their operation as “magic”, since they’re certainly sufficiently advanced technology, and didn’t someone once say something about the two being indistinguishable? ---
**Author:** ![eburacum45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eburacum45/32/8690_2.png) [@eburacum45](https://boards.straightdope.com/u/eburacum45)\ **Post date:** [June 3, 2003, 9:59am UTC](https://boards.straightdope.com/t/question-about-physics-in-the-movie-2010/178794/11 "2003-06-03T09:59:23Z")
Oh, dear- it is a fairly pointless exercise debating about the Clarketech of an imaginary advanced alien species- but I don’t think it is necessary for the Monoliths to import extra mass at all. Every second the Sun fuses ~10[sup]9[/sup]kg of hydrogen- Jupiter contains ~10[sup]26[/sup]kg of hydrogen; that should be enough to keep a small star going for a billion years. All the Monoliths have to do is to concentrate the Hydrogen into a small enough ball for fusion to be self-sustaining… of course it helps if these pieces of equipment are designed to function at a million degrees K, but like I said, it it is clarketech, which is by definition indistinguishable from magic. * * * SF worldbuilding at [http://www.orionsarm.com/main.html](http://www.orionsarm.com/main.html)