The recent plunge of the Galileo spacecraft into Jupiter got me thinking.
Why didn’t they sterilize the probe if they were so damn concerned about contaminating Europa with Earthly bacteria?
But that’s not what really pisses me off. That very same probe witnessed the Shoemaker-Levy collision in 1994, and it found evidence of organic matter in Jupiter. Organic matter means the potential for life! NASA just contaminated Jupiter with Earthly life and now we’ll never know if it already had indigenous life. :mad:
I can imagine some overqualified NASA egghead saying “There’s no way Earthly life will survive in Jupiter’s atmosphere because of this and that and a bunch of other things” Hello! It already survived being locked up next to a friggin’ plutonium reactor, not to mention several trips through radiation that “would kill a human 1,000 times over”.
Joke’s on them because there’s a chance that little stunt will ignite Jupiter, making it into a star, and kill all that precious life on Europa anyway. :mad:
Well, they didn’t sterilise the probe because back when it was launched, the potential of Europa wasn’t realised and they were unaware of the existence of such survivable bacteria. By contrast, the temperature of atmospheric re-entry into Jupiter is considered certain to vaporise just about anything that could possibly be clinging to the craft. Note that no-one said it’s likely that there are bacteria still on it, merely that it’s a tiny possibility and that it’s best to be sure it’s destroyed.
No, there isn’t. What on earth are you reading that is telling you this? Jupiter is regularly struck by much more massive objects than Galileo with no noticeable conflagration. The end of the world is not quite so nigh as you thought.
What I meant to say is not that the sheer impact would ignite Jupiter, but that we have no idea what happens if all that plutonium makes its way to the core. Really, how much do we know about what goes on inside a star, since nobody’s gone there or sent a probe into the searing heat?
Actually, we know an amazing amount about stars, their origins, and their eventual ends. Jupiter is simply too small a body for gravitational pressure to start hydrogen fusion, so no amount of space junk can turn it into a star. Our own Bad Astronomer has answered this question already on his Web site.
Aryk, I think you´ll find out that Jupiter is not a star; there was a recen thread about the (im)possibility of the plutonium carried by the Galileo prove to do any damage to Jupiter.
Aside, anyone could survive being “locked up” next to the RTG - you’d be glad of it in the depths of space because you’d be slightly warm - that’s it. (Read about the RTG here)
In case the whole “impact” thing sways anyone else, Galileo wouldn’t even tickle compared to all the other crap Jupiter puts up with. I read someplace (lost the cite) that Shoemaker Levy 9 is estimated to have hit Jupiter with an energy of 300 billion megatonnes. That’s “billion” with a pinky. Here’s some tables with energy inputs for Jupiter.
In any case, the probe will vaporize pretty quickly - Europa does not have an atmosphere, whilst Jupiter does. Recall that of all the space hardware that enters Earth’s much smaller atmosphere, the only stuff that leaves anything to hit the ground are super huge sats, and what does is burnt to heck. Jupiter was a very safe target.
So please! Start settling down now or Cassini is gonna kill you!
Course, what the BAdidn’t mention is that NASA told him that they used the SOHO satellite to take over control of Mars’ missing moon Phobos, which is really an alien spacecraft. The moonship removed all of Galileo’s deadly plutonium, seconds before impact. Disaster was thus averted, but more importantly, the conspiracy theorists suffered yet another blow to their credibility. Planet X, (Nibaru, or Zardaloo, or Boskone, or whatever) had better hurry up and get here, or no one will believe in it when it does.
Well duh, I know Jupiter is not a star, even though it already gives off more heat than it gets from the Sun. Of course it takes a body with 13 times the mass of Jupiter to ignite thermonuclear fusion processes spontaneously, which is why astronomers looking for extrasolar planets draw the line between “planet” and “companion star” at 13Mj, although the exact mass is difficult to determine unless you know the inclination…
Anyway, my point was that we don’t know if it’s possible to ignite a planet by injecting radioactive material into it. Sure, we think we know, but nobody’s ever tried it before. Of course such a (relatively) small body would probably be much dimmer and redder than even an M9 star and from Earth it would appear, by my calculations, dimmer than magnitude -17 which is about 100 times the brightness of the full moon…
At the risk of sounding somewhat skeptical, would you mind outlining your calculations? I’m, um, interested to see how you justify your claim there. What exactly do you think the processes are? Presumably, it has to be one of the three following options:
Galileo triggers fusion reactions in Jupiter. As has been pointed out, Jupiter has nothing like the requisite mass to sustain such reactions, regardless of how these are started.
Galileo triggers fission reactions in Jupiter. This would rely on Jupiter being made largely of fissile material, which it isn’t (and neither is Galileo). So it won’t.
Galileo triggers combustion reactions in Jupiter. If Jupiter’s atmosphere were combustible, firstly we could tell and secondly it would not exist, having been long ago ignited by any one of the billions of objects that have hit it in its history.
So, which of these scenarios would you like to hang your hat on?
Jupiter is too small to be a star.. According to the latest stellar models, the lowest minimum mass sufficent to ignite and sustain hydrogen fusion is approximately 80 times Jupiter’s mass, not 13.
You can’t turn a planet into a star by injecting radioactive material into it.
I suggest that you read the Web page for the full explanation, but suffice it to say that even if the Galileo were a fission bomb (which it’s not) and could trigger a fusion reaction (which it can’t), Jupiter’s hydrogen is the wrong sort and is too diffuse for making a fusion reaction.
What got me about BA’s page is that some people think NASA is deliberately trying to turn Jupiter into a star. I know scientists can be pretty stupid, but I can’t believe they’d be that stupid. I mean, I’m curious what would happen if we could, but I have a little voice in my head that tells me not to:
I know, I’ll bash my head on a wall. Bad idea, Shade. bad idea.
I know, I’ll eat breakfast today. That’s ok, Shade.
I know, I’ll turn Jupiter into a star. OK, it shouldn’t affect the earth in any way, but do you really want to be in the same solar system as that experiment, Shade?
While that is true, we also don’t know if the Gallilleo will cause monkeys to fly out of our butts. Sure, we think we know, but nobody’s ever tried this before. I ask you, are we ready for a plague of flying ass monkeys? NASA is endangering us all.
