Jupiter is Shrinking?
I’ve written about Jupiter before, but the article wasn’t directly dealing with Jupiter, as much as it was dealing with its relationship to the Sun. You can read that article by clicking the link at the bottom of this post, if you wish. In that article, I teased the fact that I had learned some very interesting things about the Jovian Giant, and that I would be posting those as a separate article once I had a little more time for more research. That research finds that Jupiter is, almost, as large as its going to get. There is strong research out there that shows that Jupiter might actually get vastly smaller!
This is a hard concept to grapple with as Jupiter has always been the largest planet in our solar system as far back as we can reach. This conclusion was reached in 1999 and published on Sciencemag.org by Tristan Guillot. The theory states that because of Jupiter’s gaseous nature and its large mass, the planet may, in fact, be turning into a brown dwarf star! [ref] To delve a little deeper, it should be known that the main difference between a brown dwarf star and a red dwarf star is one’s ability to fuse hydrogen within their core. It is a bit more complex than that, but that will work well enough for this article’s purposes.
All stars start out as giant balls of gas. That gas, at some point, gains so much mass that the gravitational pull of all that gas reacts on itself, compressing it all into a smaller package. The compression causes friction heat to build up at the core, which, if it’s mass is great enough, will cause hydrogen fusion, creating a red dwarf star. In the cases of brown dwarf stars, this same reaction occurs, but the mass of the newly formed brown dwarf is not great enough to generate the heat needed to jump-start this fusion process known as stellar ignition. These stars still emit heat and light, but at a much smaller level. Jupiter also emits a great amount of light, considering it is the fourth brightest body in our night sky behind, the Sun, the Moon and Venus.
Jupiter, actually, already performs this function. Jupiter currently emits more heat than it absorbs from the sun. Astronomer P. Bodenheimer of the Lick Observatory in Santa Cruz found that Jupiter is actually shrinking approximately 2 CM per year and that, at the time of its formation, Jupiter was about twice its current diameter. [ref] As the planet Jupiter tumbles around space, its massive gravity pulls in other gaseous matter, causing it to gain mass and size. At some point, the gravitational pull of all that gas causes that planet to compress down ever so slightly actually making the planet gain mass while losing size! The tipping point of when Jupiter would actually compress down in a manner that would be appreciable enough for us to take note from all the way over here on Earth is quite a ways away, but it is estimated that this compression would take place when Jupiter manages to gain another ~60% of it’s own mass. That is still a long way from being a brown dwarf, considering the smallest brown dwarf on record is between ~10 & ~13 times the mass of Jupiter in its current state, depending on which articles you read.
All this to the side, the reason I bring this up is because I want you to pretend, for just a moment, that Jupiter actually did end up becoming a brown dwarf. Ignoring the effects that would have on the Earth (which would be virtually impossible to predict, at this point, due to the wide variety of possible variables) I want you to imagine the classification of a new solar system WITHIN our already existing solar system! Jupiter’s 60+ moons would be reclassified as exoplanets (planets orbiting a star that is not our own)! What about the possibility that Jupiter, at some point, could gain enough mass and gravitational pull to start cannibalizing the Asteroid Belt that separates the orbit of Mars from the orbit of Jupiter, if not the Rings of Saturn and possibly even Saturn itself! Saturn, also being a gas giant, would contribute to the growth of Jupiter in such a way that it might start to pull in others! At some point, the growth could get so massive that most of our solar system could be wiped out with an end game that has the Sun and Jupiter in a binary system. Considering the fact that most astrophysicists think the Sun will, one day, expand from its current yellow dwarf status to red giant status expanding its borders so it would actually be larger than the orbit of the Earth. Could Jupiter have an effect on that process? I think it’s a very interesting question and something amazing to ponder over.
Speaking of exoplanets, I have a some info about a newly discovered exoplanet that is currently orbiting a binary star! Should make for interesting reading as I, currently, have almost no info about it. I plan to learn a bunch about the exoplanet and report back on Wednesday.
*UPDATE* In the original publishing of this article, I mistakenly called the Sun a red dwarf when it is, in fact, a yellow dwarf. The proper corrections were made to the article and I want to thank Reddit user “Bonetastic” for noticing the mistake. Sorry for any confusion. *UPDATE*
Posted on September 3, 2012, in Geek, Nerd, Science, Space and tagged albany, alloy matt, blue, brown dwarf, coinopkids, corvallis, gas giant, gaseous planet, geek, jupiter, jupiter photo, lebanon, matt jacobs, nerd, oregon, shrinking, space, star. Bookmark the permalink. Leave a comment.