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07/30/2018
Moons, Blazars and Spaceflight Debris
CHAPTER 94 Space Stuff
As I started to write this column, I had just finished watching the final match of the World Cup between France and Croatia. I am not all that interested in soccer. However, our live-in caregiver is a big fan and she taught me a lot about the finer points of the game and of the World Cup. After the game I was intrigued as Vladimir Putin placed medals around the necks of the Croatian and French teams while President Macron of France and President Kolinda Grabar-Kitarovik of Croatia stood by him, embracing the players and coaches in a drenching rain. For a while, Putin was the only one covered with an umbrella, but not the other two leaders, who got soaking wet. Putin and Russia certainly deserve credit for a successful staging of this major sporting event. Equally impressive was Putin's handling of our befuddled leader in Helsinki. After that disaster, as a registered Republican I was heartened to see at least a few of my party stand up for some degree of rational behavior.
Well, now that I've probably lost half my audience, let's get back to other things going on in our universe. A recent development is the report that astronomers have found a bunch of 10 new moons orbiting Jupiter, bringing the grand total of such objects to 79. The search for objects orbiting Jupiter dates back over 400 years to 1610, when Galileo found four of Jupiter's largest moons. Scott Sheppard, of the Carnegie Institution for Science, has been in the forefront of those searching more recently for moons around Jupiter, having been involved in the discovery of 48 of Jupiter's moons. However, this latest discovery was a byproduct of another quest.
Some astronomers are convinced there is a Planet 9 lurking in the outskirts of our solar system. Sheppard and his team were engaged in a search for that hypothetical object when they found that Jupiter happened to be in the same region of the sky. Sheppard and his team were working with a special telescope outfitted with a camera suited to minimizing the light from a planet that would blot out dim moons. The camera also could cover very large areas of the sky so it only took a few shots to take photos of the region around Jupiter. The result: last year in June they found two new moons and this year added another 10. The new moons are not large, only a few miles or tens of miles in diameter. While most of these moons are nothing special insofar as Jupiter's moons are concerned, one is a renegade.
Most of Jupiter's moons fall into one of two categories, prograde or retrograde. The inner moons are typically prograde, that is, they orbit Jupiter in the same direction that Jupiter revolves. The outer moons orbit in the opposite direction, hence retrograde. One of the newly discovered moons, tentatively named Valetudo, orbits in the outer group but in the opposite, prograde direction and crosses the orbits of the other outer group of moons. Chances are that Valetudo will crash into one of the other moons someday.
After I had finished writing the above, our refrigerator also went rogue, the freezer still working but the fan blowing the cold air into the main section of the frig had died. As a result we spent five days relying on ice cubes and coolers to preserve what food we didn't have to throw out. Which provides me with a perfect segue to the next topic - blazars and IceCube. While Sheppard and his coworkers are busy finding moons and searching for a planet using a telescope, other astronomers are using an ice cube to capture the tiniest of particles, neutrinos, emanating from huge distant objects known as blazars. OK, the ice cube these researchers are using isn't your typical ice cube. This one is located at the South Pole and is a cube of clear ice one kilometer on a side; that is a one cubic kilometer ice cube! The facility consists of 86 vertical strings, spaced 125 meters apart, each string carrying 60 optical detectors, the lowest ones at a depth of about 2450 meters.
When a neutrino strikes a nucleus in a frozen water molecule in the ice, other particles fly off and emit light known as Cherenkov radiation. The detectors pick up the light and by following which detectors light up and the timing and brightness of the light, the researchers can calculate the path of the neutrino. I personally am amazed they can precisely calculate the path of this most ephemeral of particles and project that path in the ice like an arrow out to the sky and search for something going out there that might have produced the neutrino. On the other hand, I shouldn't be surprised after seeing how astronomers recently pinpointed two neutron stars merging based on gravitational waves and gamma ray bursts being detected from something that happened a billion or more years ago.
Let's discuss this particular neutrino. The vast majority of neutrinos detected by IceCube are low energy neutrinos formed when cosmic rays strike something in our atmosphere. However, this neutrino joins perhaps a dozen or so neutrinos detected every year that have extremely high energies. When IceCube reported this energetic neutrino, astronomers did find a recent flare-up in a blazar close to the predicted path extrapolated from the IceCube data. What is a blazar? A blazar is just a quasar pointed directly at us. OK, what is a quasar? At the center of virtually every galaxy is, as we have in the center of our own Milky Way galaxy, a huge black hole. When one of these supermassive black holes is feeding on gases or gobbling up massive stuff, the gases and stuff can get extremely hot and bright. Jets of matter and gas can be ejected from the galaxy. If such a jet happens to be pointed our way it can be very bright and hot; hence the term blazar.
Back to our particular neutrino. As I said there is a blazar located out there that could be the source of this neutrino. When the astronomers combed through past data, they found that the same blazar, some 4 billion light-years away from us, had flared up back in 2014-2015 and that an excess of very high energy neutrinos had been detected by IceCube at that time. The net result is that the IceCube workers are not claiming that they've definitely found the source of their one little guy but the evidence certainly indicates a strong likelihood they are right.
I began this column talking about Putin and Russia. With all the talk about Russia's meddling in our election and possible hanky panky involving Trump and the Russians, I've been surprised that I have heard little or nothing from Trump about one area where we and the Russians have been cooperating quite closely for years. I'm talking, of course, about the International Space Station (ISS) and the fact that, ever since we stopped sending personnel and supplies there on our space shuttles, the Russians have been ferrying our astronauts and supplies to and from ISS using the Baikonur Cosmodrome in Kazakhstan. Baikonur, which is now leased by Russia from Kazakhstan, has been the center for space launches dating back to the Soviet Union's launching of Sputnik and then Yuri Gagarin to begin the humans-in-space era. We have been paying the Russian space agency Roscosmos between $21 million and $82 million for each round trip seat on Soyuz spacecraft. From 2006 to 2018 some 3.4 billion dollars have been spent on our astronauts' Soyuz travels.
In one of my Discover magazine emails I found an article dated June 7, 2018 by Paul Cooper titled "In Russia's Space Graveyard, Locals Scavenge Fallen Spacecraft for Profit". In contrast to our main launch site at Cape Canaveral in Florida, the Baikonur launch site is in the center of a major land mass. While our launch debris falls into the ocean the Russian debris falls on land located along the flight path above the Altai mountain range in Central Asia. The Russians typically use a 700 ton 4-stage Proton rocket to boost a 6 ton cargo into orbit. The first stage usually falls away within 90 kilometers of launch but the second stage travels about 1000 kilometers before it separates and falls to earth. This puts it over the Altai mountains and there are people living there. Some people supplement their meager income salvaging the rocket parts, which may end up in someone's backyard! Or worse, on someone's home. Those living along the flight path in a prescribed area do receive a 24- hour warning of a launch so they can take shelter. However, if something goes wrong in the launch the rocket can veer off its normal path and crash, sometimes with unexpended fuel on board. In 2011 a rocket had problems in the first few minutes and it crashed in the Altai mountains with lots of fuel still on board, blowing out windows up to 100 kilometers away! Luckily, nobody was hurt.
Some villagers living along the path of the rockets go out following a launch to recover the metal parts of the rockets, often arriving while the debris is still hot and even burning. The metal parts of the rockets are used to make things such as tools, roofs of chicken coops, plows or sledges for children. The light metals such as aluminum and titanium used in the rockets can be valuable for the scrap dealers. Back in the days of the old Soviet Union, the government didn't want to have any secrets revealed and they would gather up the debris but now it's just left where it falls to either just rust away or get picked up by the residents.
The debris can give off toxic vapors, especially if there's rocket fuel left in the debris, as is often the case. One compound in Russian fuel is a known cause of cancer and birth defects and in one village it is said that every baby there is born with jaundice. The article poses the moral question of the quest for exploring our universe causing suffering to poor villagers on the path of these rockets. It's something I had not considered or been aware of. Actually the Russians are building a new launch facility, the Vostochny Cosmodrome, in the far east of Russia. At least three launches have been made from Vostochny, one of which failed. The location of Vostochny is close enough to the Pacific Ocean that stages of the rockets can be dropped into the ocean instead of on land. Vostochny is still under construction and won't be ready for launching of Russia's largest rockets for quite some time. There's a possibility that SpaceX or some other company, Boeing possibly, will be launching our astronauts by the time Vostochny is completed.
Next column, hopefully, September 1
Allen F. Bortrum
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