Io is the first Galilean moon of Jupiter, it is slightly larger than Earth’s moon. Io experiences intense tidal heating due to its elliptical orbit and orbital resonance with Europa and Ganymede. This makes Io the most geologically active moon in our solar system. Io’s interior is composed of molten iron sulphide, and the surface is a crust of sulfur and silicon. Io has more than 400 active volcanoes, which can eject lava plumes more than 500 kilometers above the surface. Some of the material from Io’s volcanic eruptions leaves the moon and orbits Jupiter, producing a plasma torus. Io also has lakes of lava called paterae, which can also create eruptions. The most dramatic paterae are Loki, Tvashtar, and Tupan. The constant volcanic activity creates a thin atmosphere of sulfur dioxide and sodium chloride. Io is an interesting model for exoplanets with intense geological activity, such as COROT-7b.
Europa is the second Galilean moon of Jupiter. It is slightly smaller than Earth’s moon and has a much different composition. The surface of Europa is made of ice, covered with fractures and frozen icebergs. The fractures are surrounded by a sulfurous material that appear to have leaked out its core. Due to orbital resonance with Io and Ganymede, Europa experiences tidal heating of its interior. Together with the discovery of an induced magnetic field around the moon, there is strong evidence that Europa has a subsurface ocean of liquid water. This makes Europa one of the most likely places in our solar system to look for life.
So (I hope) without spoiling the fun, I’m just going to briefly review this movie for you guys. I’m not a professional critic or anything, but I do love to poke fun at science fiction films. And in any case, this is one of the more superb sci-fi films that I’ve watched as of recently. And luckily, it did not fall too far into the realm of physical implausibility.
I was, indeed, impressed by how accurate the science. From the engineering feats, to the space travel, to potential life in extreme environments—most of the scientific references made were, to my knowledge, correct. (Except for the fiction part of course). But what’s more striking is the almost too-optimistic generalization about the currents of space exploration. The problem is, it’s highly unlikely that we would send a crew of scientists to Europa before we had even attempt to reach Mars, yet alone the Moon again. I guess it was unrealistic to me that the “humanity’s need for discovery” was suddenly “realized”. It’s going to take a lot more than—“we just want to see what’s going on over there”—to get us to okay a manned mission to the outskirts of Jupiter. Or maybe I’m just bitter that at the end of the day, this is still only a movie.
Other than that, it was actually pretty terrifying to watch. I won’t go into details, but there were moments when I panicked and nearly screamed. I also enjoyed the acting—the characters really did a great job capturing the heart of a scientist. I was awed, and petrified at the same time at the mystery and profound knowledge that was within the grasp of the crew members when they were on Europa—all they need to do was gather data, observe, and send the discovery back to Earth. It’s so fundamentally moving, with an almost romantic sentiment, I would say the least. If humanity ever has the audacity to push themselves towards such a large frontier, I would only hope to be alive on that day to see, if after all, we are alone.
And of course, because this is in the field of my interest, I hold it at quite a high value. For one thing, I’m off to study Earth and life so that one day I can study life elsewhere. I would really love to take part in the search once I’m an established scientist, especially in our neighboring planets. We know astrobiology is not restricted to only our Solar System—that’s quite a geocentric way of thinking— but we have to start somewhere! Europa is one. And I would indeed die very happy if in this lifetime, I get to see humanity reach such a mysterious location— where perhaps, just perhaps, our cosmic brothers and sisters might be stirring, aimlessly underneath the cold and darkness. It would really be something, wouldn’t it?
If we landed on Europa, what would we want to know?
Most of what scientists know of Jupiter’s moon Europa have gleaned from a dozen or so close flybys from NASA’s Voyager 2 spacecraft in 1979 and NASA’s Galileo spacecraft in the mid-to-late 1990s. Even in these fleeting, paparazzi-like encounters, scientists have seen a fractured, ice-covered world with tantalizing signs of a liquid water ocean under its surface. Such an environment could potentially be a hospitable home for microbial life. But what if we got to land on Europa’s surface and conduct something along the lines of a more in-depth interview? What would scientists ask? A new study in the journal Astrobiology authored by a NASA-appointed science definition team lays out their consensus on the most important questions to address.
"If one day humans send a robotic lander to the surface of Europa, we need to know what to look for and what tools it should carry," said Robert Pappalardo, the study’s lead author, based at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. "There is still a lot of preparation that is needed before we could land on Europa, but studies like these will help us focus on the technologies required to get us there, and on the data needed to help us scout out possible landing locations. Europa is the most likely place in our solar system beyond Earth to have life today, and a landed mission would be the best way to search for signs of life."
The team found the most important questions clustered around composition: what makes up the reddish “freckles” and reddish cracks that stain the icy surface? What kind of chemistry is occurring there? Are there organic molecules, which are among the building blocks of life?
Additional priorities involved improving our images of Europa - getting a look around at features on a human scale to provide context for the compositional measurements. Also among the top priorities were questions related to geological activity and the presence of liquid water: how active is the surface? How much rumbling is there from the periodic gravitational squeezes from its planetary host, the giant planet Jupiter? What do these detections tell us about the characteristics of liquid water below the icy surface?
"Landing on the surface of Europa would be a key step in the astrobiological investigation of that world," said Chris McKay, a senior editor of the journal Astrobiology, who is based at NASA Ames Research Center, Moffett Field, Calif. "This paper outlines the science that could be done on such a lander. The hope would be that surface materials, possibly near the linear crack features, include biomarkers carried up from the ocean."
A Mission to Europa —NASA Zeroes in On What They’ll Search For | The Daily Galaxy
Most of what scientists know of Jupiter’s moon Europa they have gleaned from a dozen or so close flybys from NASA’s Voyager 2 spacecraft in 1979 and NASA’s Galileo spacecraft in the mid-to-late 1990s. Even in these fleeting, paparazzi-like encounters, scientists have seen a fractured, ice-covered world with tantalizing signs of a liquid water ocean under its surface. Such an environment could potentially be a hospitable home for microbial life. But what if we got to land on Europa’s surface and conduct something along the lines of a more in-depth interview? What would scientists ask? A new study in the journal Astrobiology authored by a NASA-appointed science definition team lays out their consensus on the most important questions to address.
Perseid Meteor Shower 2013 With a rate of 80 meteors/hour or more, this is something you definitely don’t want to miss. Meteors will appear all across the sky but will seem to radiate from the Perseus constellation. They will be visible all around the world, however, southern hemisphere viewers will see lower rates. There is also a smaller meteor shower peaking this weekend (around July 28). Read the Full Article Here
If you have never heard of the Fluxtimator before, it’s this tool that estimates the meteor shower rates for you. So you select the time, location and the name of the meteor shower and it will give you some numbers on what to expect. I found it to be fairly accurate over the last few meteor showers I watched.
I made this gif showing the next few days for the Perseids this year. I selected Phoenix because I live near there and as you see it is expected to max out around 89 apparently. It stops at around 6am because that’s when the Sun rises and around the 14th you can see a dip forming on the left side of the line. That is from the Moon getting brighter (waxing) and rising earlier trying to ruin the show, but good thing it was a few days late this year.
If you read my article on the Perseids already you would know that more-southern areas will see lower rates. If you go a little bit more north than 33 degrees latitude (Phoenix) some areas will reach rates of over a 100!
(I know right, but make sure you get away from light pollution and also being on a mountain helps)
But the point for this is you can start watching for Perseids now! It is definitely not too early. I already saw some Perseid fireballs a few days ago along with some Delta Aquarids last week. You will definitely see more and more fireballs as the days progress towards the peak, and according to NASA, the Perseids produce the most fireballs out of all the other meteor showers.
So get on out there fellow stargazers, look up at night and enjoy the show! And if you want to try and photograph some meteors or just need some awesome jams to listen to, take this with you.
The scientific man does not aim at an immediate result. He does not expect that his advanced ideas will be readily taken up. His work is like that of the planter — for the future. His duty is to lay the foundation for those who are to come, and point the way. He lives and labors and hopes.