Arthur Clarke had a soft spot for Jupiter and wrote about it often. In A Meeting with Medusa, a crew uses a hot air balloon to descend from their spacecraft to Jupiter’s surface, where they find all kinds of strange stuff, like flying bioluminescent plankton and floating jellyfish a mile wide. In 2001: A Space Odyssey, Jupiter is the destination (at least, in the movie it is), and in 2010: Odyssey Two, Jupiter — and the mysterious monolith orbiting it — is the focus. In what may have been a particularly prescient plot twist, Clarke also describes life forms in the waters of Europa. As the crew explores the Jovian system, a “Great Black Spot” appears on Jupiter, which grows exponentially — a huge swarm of self-replicating monoliths that consume the planet and…well, I won’t tell you. Let’s just say Jupiter is renamed Lucifer. Clarke’s “Great Black Spot” is, of course, a spin on the most distinguishable birthmark on Jupiter. But instead of growing like the Great Black Spot, Jupiter’s Great Red Spot is shrinking.
Our Moon May Not Be Able To Have Its Own Mini-Moon, But A Meteorite Recently Exploded On The Lunar Surface
When you realize that planets like Saturn have 60 moons, and Jupiter has 63, you have to wonder whether moons can have their own moons. Saturn’s satelite Titan is larger than the planet Mercury, so it’s not hard to imagine another rock circling it. Fraser Cain, publisher of Universe Today, one of my favorite space publications, tackled this question, and has dashed my hopes of discovering an infinite series of moons. It turns out that a moon can’t have a moon—unless some specific stuff is going on, which we’ll talk about later. At least the reasons this can’t happen are interesting, and that makes everything okay.
Apparently, “moon” has no explicit definition. If you look it up, you’ll find references to Earth’s Moon, but no official definition about what moons are in general. I thought science had this stuff nailed down. Moons do have some consistent attributes, though: they’re whole, sold objects that orbit around a bigger body, probably a planet, probably orbiting a star. Whatever the moon orbits is orbiting something else, etc. Technically, the Moon does have a moon, or at least something distinct orbiting it: NASA’s Lunar Reconnaissance Orbiter, which has been circling and photographing our Moon since 2009. But its lifespan is limited, and sheds light on why no moons in our Solar System can have their own satellites.
Jupiter is set to give Mars and Saturn a run for their money when it comes to being the most talked-about planet in the coming years. The news that Jupiter’s moon Europa contains water vapor plumes helped solidify the Solar System’s biggest planet as a particularly important exploration target, especially when it comes to the search for life. A number of missions, including Juno, which is scheduled to arrive in 2016, have Jupiter in their sights, including the ESA’s JUICE (JUpiter ICy moon Explorer) probe, which is due to launch in 2022. Now it seems that Russia will join the fun, presumably by linking up with the JUICE mission by sending a probe to explore Jupiter’s moon Ganymede.
Scientists consider Jupiter’s moon Europa one of the best candidates for harboring alien life in the solar system. Its atmosphere is mostly made up of oxygen and it has a smooth surface of ice (not to mention a rocky mantle and likely an iron core — sound familiar?). Based on data gathered by the Galileo spacecraft, which arrived at the Jovian moon in 1995, scientists theorize that under Europa’s icy surface exists an ocean of water, kept liquid by heat generated from tidal forces. Recent evidence published in the Science Express journal lends support to this theory, as data from the Hubble indicates plumes of water vapor at Europa’s south pole, suggesting that there is indeed liquid water under the surface.
Even though NASA has been crippled by the government shutdown, maintaining enough staff and operations to keep our ISS astronauts alive, its spacecraft continue on their missions, supporting the argument that robots and artificial intelligence are indeed smarter than humans. Today, spacecraft Juno will fly by Earth for a boost that will help it reach speeds of roughly 165,000 miles per hour as it heads toward Jupiter.
Remember the asteroid impact on Jupiter that happened two weeks ago? Well, apparently Jupiter doesn’t. What was once a chance sighting of a comparatively common impact event on the largest planet in our solar system has turned into something of an unsolvable puzzle. It seems while the flash was the perfect indicator for an impact, the lack of the usual follow-up evidence has left astronomers scratching their heads as to what hit the gas giant.
Ever since the impact of the Shoemaker-Levy 9 comet in 1995, astronomers have had a discernible chain of events that they could point to when it comes to large impact events on Jupiter. Once a comet or other large space debris is pulled into Jupiter, first you have the impact (which, given the correct placement of equipment, is visible to astronomers), and then you have the deep black scarring that denotes the impactor’s explosion in the planet’s atmosphere. In an email to Universe Today, SETI astronomer Franck Marchis tells why this tell-tale scar is so important to astronomers.
By performing spectroscopic measurement of the debris field we hope to be capable of determining the nature of the impactor. Without debris field it is virtually impossible since the bolide burned in the upper atmosphere. One day we may be capable of [recording] a spectrum of the meteor itself (during the impact) but right now we don’t have such capabilities.