NASA will make a “surprising” announcement about Jupiter’s moon Europa on Monday, Sept. 26th, at 2:00 PM EDT. They haven’t said much, other than there is “surprising evidence of activity that may be related to the presence of a subsurface ocean on Europa.” Europa is a prime target for the search for life because of its subsurface ocean.
The new evidence is from a “unique Europa observing campaign” aimed at the icy moon. The Hubble Space Telescope captured the images in these new findings, so maybe we’ll be treated to some more of the beautiful images that we’re accustomed to seeing from the Hubble.
Images from NASA’s Galileo spacecraft show the intricate detail of Europa’s icy surface. Image: NASA/JPL-Caltech/ SETI Institute
We always welcome beautiful images, of course. But the real interest in Europa lies in its suitability for harboring life. Europa has a frozen surface, but underneath that ice there is probably an ocean. The frozen surface is thought to be about 10 – 30 km thick, and the ocean may be about 100 km (62 miles) thick. That’s a lot of water, perhaps double what Earth has, and that water is probably salty.
Back in 2012, the Hubble captured evidence of plumes of water vapor escaping from Europa’s south pole. Hubble didn’t directly image the water vapor, but it “spectroscopically detected auroral emissions from oxygen and hydrogen” according to a NASA news release at the time.
This artist’s illustration shows what plumes of water vapour might look like being ejected from Europa’s south pole. Image: NASA, ESA, L. Roth (Southwest Research Institute, USA/University of Cologne, Germany) and M. Kornmesser.
There are other lines of evidence that support the existence of a sub-surface ocean on Europa. But there are a lot of questions. Will the frozen top layer be several tens of kilometres thick, or only a few hundred meters thick? Will the sub-surface ocean be warm, liquid water? Or will it be frozen too, but warmer than the surface ice and still convective?
Two models of the interior of Europa. Image: NASA/JPL.
Hopefully, new evidence from the Hubble will answer these questions definitively. Stay tuned to Monday’s teleconference to find out what NASA has to tell us.
These are the scientists who will be involved in the teleconference:
Paul Hertz, director of the Astrophysics Division at NASA Headquarters in Washington
William Sparks, astronomer with the Space Telescope Science Institute in Baltimore
Britney Schmidt, assistant professor at the School of Earth and Atmospheric Sciences at Georgia Institute of Technology in Atlanta
Jennifer Wiseman, senior Hubble project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland
The NASA website will stream audio from the teleconference.
The Moon crosses the Hyades on July 29th, 2016. Image credit and copyright: Alan Dyer
This week, we thought we’d try an experiment for tonight’s occultation of Aldebaran by the Moon. As mentioned, we’re expanding the yearly guide for astronomical events for the year in 2017. We’ve done this guide in various iterations since 2009, starting on Astroguyz and then over to Universe Today, and it has grown from a simple Top 10 list, to a full scale preview of what’s on tap for the following year.
You, the reader, have made this guide grow over the years, as we incorporate feedback we’ve received.
Anyhow, we thought we’d lay out this week’s main astro-event in a fashion similar to what we have planned for the guide: each of the top 101 events will have a one page entry (two pages for the top 10 events) with a related graphic, fun facts, etc.
So in guide format, tonight’s occultation of Aldebaran would break down like this:
Wednesday, September 21st: The Moon Occults Aldebaran
The occultation footprint of tonight’s Aldebaran event.
Image credit Occult 4.2
The 67% illuminated waning gibbous Moon occults the +0.9 magnitude star Aldebaran. The Moon is two days prior to Last Quarter phase during the event. Both are located 109 degrees west of the Sun at the time of the event. The central time of conjunction is 22:37 Universal Time (UT). The event occurs during the daylight hours over southeast Asia, China, Japan and the northern Philippines and under darkness for India, Pakistan and the Arabian peninsula and the Horn of Africa. The Moon will next occult Aldebaran on October 19th. This is occultation 23 in the current series of 49 running from January 29th 2015 to September 3rd, 2018. This is one of the more central occultations of Aldebaran by the Moon for 2016.
The view from India tonight, just before the occultation begins. Image credit: Stellarium
Fun Fact-In the current century, (2001-2100 AD) the Moon occults Aldebaran 247 times, topped only by Antares (386 times) and barely beating out Spica (220 times).
Or maybe, another fun fact could be: A frequent setting for science fiction sagas, Aldebaran is now also often confused in popular culture with Alderaan, Princess Leia’s late homeworld from the Star Wars saga.
Like it? Thoughts, suggestions, complaints?
Now for the Wow! Factor for tonight’s occultation. Aldebaran is 65 light years distant, meaning the light we’re seeing left the star in 1951 before getting photobombed by the Moon just over one second before reaching the Earth.
There are also lots of other occultations of fainter stars worldwide over the next 24 hours, as the Moon crosses the Hyades.
And follow that Moon, as a series of 20 occultations of the bright star Regulus during every lunation begins later this year on December 18th.
Gadi Eidelheit managed to catch the March 14th, 2016 daytime occultation of Aldebaran from Israel:
And also in the ‘Moon passing in front of things’ department, here’s a noble attempt at capturing a difficult occultation of Neptune by the Moon last week on September 15th, courtesy of Veijo Timonen based in Hämeenlinna Finland:
Lets see, that’s a +8th magnitude planet next to a brilliant -13th magnitude Moon, one million (15 magnitudes) times brighter… it’s amazing you can see Neptune at all!
Last item: tomorrow marks the September (southward) equinox, ushering in the start of astronomical fall in the northern hemisphere, and the beginning of Spring in the southern. The precise minute of equinoctial crossing is 14:21 UT. In the 21st century, the September equinox can fall anywhere from September 21st to September 23rd. Bob King has a great recent write-up on the equinox and the Moon.
Here’s EVERY occultation of Aldebaran from 2015 through 2018. (Click to enlarge) Credit: Occult 4.2.
Don’t miss tonight’s passage of Aldebaran through the Hyades, and there’s lots more where that came from headed into 2017!
SpaceX founder and CEO Elon Musk. Credit: Ken Kremer/kenkremer.com
For Elon Musk, it’s always been about Mars. Musk, and his company SpaceX, haven’t always been explicit about how exactly they’ll get to Mars. But SpaceX’s fourteen years of effort in rocketry have been aimed at getting people into space cheaper, and getting people to Mars.
Musk has revealed hints along the way. One of the boldest was his statement at Code Conference 2016. At that conference he said, “I think, if things go according to plan, we should be able to launch people probably in 2024, with arrival in 2025.”
He went on to explain it this way: “The basic game plan is we’re going to send a mission to Mars with every Mars opportunity from 2018 onwards. They occur approximately every 26 months. We’re establishing cargo flights to Mars that people can count on for cargo.”
Those comments certainly removed any lingering doubt that Mars is the goal.
But a recent Tweet from Musk has us wondering if Mars will just be a stepping stone to more distant destinations in our Solar System. On Sept. 16th, Musk tweeted:
Turns out MCT can go well beyond Mars, so will need a new name…
And the new name is Interplanetary Transport System (ITS).
So, is SpaceX developing plans to go beyond Mars? Is the plan to establish cargo flights to Mars still central to the whole endeavour? Does the name change from Mars Cargo Transporter (MCT) to Interplanetary Transport System (ITS) signal a change in focus? These questions may be answered soon, on September 27th, when Musk will speak at the International Astronautical Congress (IAC), in Guadalajara, Mexico.
Musk hinted back in January that he would be revealing some major details of the MCT at the IAC later this month. In January, he said at the StartmeupHK Festival in Hong Kong that “I’m hoping to describe that architecture later this year at IAC … and I think that will be quite exciting.”
So, lots of hints. And these hints bring questions. Is SpaceX developing a super heavy rocket of some type? A BFR? If the Mars Colonial Transport system can go much further than Mars, maybe to the moons of the gas giants, won’t that require a much larger rocket than the Falcon Heavy?
In the past, SpaceX has conceptualized about larger rockets and the engines that would power them. At the 2010 American Institute of Aeronautics and Astronautics (AIAA) Joint Propulsion Conference, SpaceX presented some of these conceptual designs. They featured a super-heavy lift vehicle larger than the Falcon Heavy, dubbed the Falcon X. Beyond that, and in increasingly powerful designs, were the Falcon X Heavy, and the Falcon XX Heavy.
These were only concepts, but it’s six years later now. Surely, any further thinking around a super-heavy lift vehicle would have started there. And if the MCT can now go well beyond Mars, as Musk said in his Tweet, there must be a more powerful rocket. Mustn’t there?
So with one tweet, Musk has sucked the air out of the room, and got everybody speculating. But Musk isn’t the only one with eyes on building a greater human presence in space. He has a competitor: Jeff Bezos, former Amazon CEO, and his company Blue Origin.
The New Shepard reusable rocket is Blue Origin’s flagship. Image: Blue Origin
The original space race pitted the USA against the USSR in a battle for scientific supremacy and prestige. The USA won that race, and they’re still reaping the benefits of that technological victory. But a new race might be brewing between Musk and Bezos, between SpaceX and Blue Origin.
The two companies haven’t been directly competing. They’ve both been working on reusable rockets, but Blue Origin has concerned itself with sub-orbital rocketry designed to take people into space for a few minutes. Space tourism, if you will. SpaceX’s focus has always been on orbital capability, and more.
But not to be outdone by SpaceX, Blue Origin has recently announced the New Glenn orbital launch vehicle, to be powered by seven of their new, powerful, BE-4 engines.
In rocketry, size definitely matters. Image: Blue Origin
There’s definitely some one-upmanship going on between Musk and Bezos. So far, it’s mostly been civil, with each acknowledging each other’s achievements and milestones in rocketry. But they’re also both quick to point out why they’re better than the other.
Bezos, with the announcement of the New Glenn orbital launch vehicle, and the BE-4 engines that will power it, took every opportunity to mention the fact that his company spends zero tax dollars, while SpaceX benefits from financial arrangements with NASA. Musk, on the other hand, likes to point out the fact that Blue Origin has never delivered anything into orbit, while SpaceX has delivered numerous payloads into orbit successfully.
But for now, anyway, the focus is on SpaceX, and what Musk will reveal at the upcoming IAC Congress. If he reveals a solid plan for recurring cargo missions to Mars, the excitement will be palpable. And if he reveals plans to go further than Mars, with much larger rockets, we may never catch our breaths.
Eta Carinae, one of the most massive stars known. Credit: NASA
The Crab Nebula; at its core is a long dead star… Image credit: NASA, ESA, J. Hester and A. Loll (Arizona State University)
Our sky is blanketed in a sea of stellar ghosts; all potential phantoms that have been dead for millions of years and yet we don’t know it yet. That is what we will be discussing today. What happens to the largest of our stars, and how that influences the very makeup of the universe we reside in.
We begin this journey by observing the Crab Nebula. Its beautiful colors extend outward into the dark void; a celestial tomb containing a violent event that occurred a millennia ago. You reach out and with the flick of your wrist, begin rewinding time and watch this beautiful nebulae begin to shrink. As the clock winds backwards, the colors of the nebula begin to change, and you notice that they are shrinking to a single point. As the calendar approaches July 5, 1054, the gaseous cloud brightens and settles onto a single point in the sky that is as bright as the full moon and is visible during the day. The brightness fades and eventually there lay a pinpoint of light; a star that we don’t see today. This star has died, however at this moment in time we wouldn’t have known that. To an observer before this date, this star appeared eternal, as all the other stars did. Yet, as we know from our privileged vantage point, this star is about to go supernova and birth one of the most spectacular nebulae that we observe today.
Stellar ghosts is an apt way of describing many of the massive stars we see scattered throughout the universe. What many don’t realize is that when we look out deep into the universe, we are not only looking across vast distances, but we are peering back into time. One of the fundamental properties of the universe that we know quite well is that light travels at a finite speed: approximately 300,000,000 m/s (roughly 671,000,000 mph). This speed has been determined through many rigorous tests and physical proofs. In fact, understanding this fundamental constant is a key to much of what we know about the universe, especially in respect to both General Relativity and Quantum Mechanics. Despite this, knowing the speed of light is key to understanding what I mean by stellar ghosts. You see, information moves at the speed of light. We use the light from the stars to observe them and from this understand how they operate.
A decent example of this time lag is our own sun. Our sun is roughly 8 light-minutes away. Meaning that the light we see from our star takes 8 minutes to make the journey from its surface to our eyes on earth. If our sun were to suddenly disappear right now, we wouldn’t know about it for 8 minutes; this doesn’t just include the light we see, but even its gravitational influence that is exerted on us. So if the sun vanished right now, we would continue in our orbital path about our now nonexistent star for 8 more minutes before the gravitational information reached us informing us that we are no longer gravitationally bound to it. This establishes our cosmic speed limit for how fast we can receive information, which means that everything we observe deep into the universe comes to us as it was an ‘x’ amount of years ago, where ‘x’ is its light distance from us. This means we observe a star that is 10 lightyears away from us as it was 10 years ago. If that star died right now, we wouldn’t know about it for another 10 years. Thus, we can define it as a “stellar ghost”; a star that is dead from its perspective at its location, but still alive and well at ours.
As covered in a previous article of mine (Stars: A Day in the Life), the evolution of a star is complex and highly dynamic. Many factors play an important role in everything from determining if the star will even form in the first place, to the size and thus the lifetime of said star. In the previous article mentioned above, I cover the basics of stellar formation and the life of what we call main sequence stars, or rather stars that are very similar to our own sun. Whereas the formation process and life of a main sequence star and the stars we will be discussing are fairly similar, there are important differences in the way the stars we will be investigating die. Main sequence star deaths are interesting, but they hardly compare to the spacetime-bending ways that these larger stars terminate.
As mentioned above, when we were observing the long gone star that lay at the center of the Crab Nebula, there was a point in which this object glowed as bright as the full moon and could be seen during the day. What could cause something to become so bright that it would be comparable to our nearest celestial neighbor? Considering the Crab Nebula is 6,523 lightyears away, that meant that something that is roughly 153 billion times farther away than our moon was shining as bright as the moon. This was because the star went supernova when it died, which is the fate of stars that are much larger than our sun. Stars larger than our sun will end up in two very extreme states upon its death: neutron stars and black holes. Both are worthy topics that could span weeks in an astrophysics course, but for us today, we will simply go over how these gravitational monsters form and what that means for us.
Inward force of gravity versus the outward pressure of fusion within a star (hydrostatic equilibrium) Credit: NASA
A star’s life is a story of near runaway fusion contained by the grip of its own gravitational presence. We call this hydrostatic equilibrium, in which the outward pressure from the fusing elements in the core of a star equals that of the inward gravitational pressure being applied due to the star’s mass. In the core of all stars, hydrogen is being fused into helium (at first). This hydrogen came from the nebula that the star was born from, that coalesced and collapsed, giving the star its first chance at life. Throughout the lifetime of the star, the hydrogen will be used up, and more and more helium “ash” will condense down in the center of the star. Eventually, the star will run out of hydrogen, and the fusion will briefly stop. This lack of outward pressure due to no fusion taking place temporarily allows gravity to win and it crushes the star downwards. As the star shrinks, the density, and thus the temperature in the core of the star increases. Eventually, it reaches a certain temperature and the helium ash begins to fuse. This is how all stars proceed throughout the main portion of its life and into the first stages of its death. However, this is where sun-sized stars and the massive stars we are discussing part ways.
The core and subsequent layers of a dying star. Each layer has been left over from millions of years of fusing each subsequent element into the next one. This is a snapshot of a massive star about to erupt. Credit: Wikimedia
A star that is roughly near the size of our own sun will go through this process until it reaches carbon. Stars that are this size simply aren’t big enough to fuse carbon. Thus, when all the helium has been fused into oxygen and carbon (via two processes that are too complex to cover here), the star cannot “crush” the oxygen and carbon enough to start fusion, gravity wins and the star dies. But stars that have sufficiently more mass than our sun (about 7x the mass) can continue on past these elements and keep shining. They have enough mass to continue this “crush and fuse” process that is the dynamic interactions at the hearts of these celestial furnaces.
These larger stars will continue their fusion process past carbon and oxygen, past silicon, all the way until they reach iron. Iron is the death note sung by these blazing behemoths, as when iron begins to fill their now dying core, the star is in its death throws. But these massive structures of energy do not go quietly into the night. They go out in the most spectacular of ways. When the last of the non-iron elements fuse in their cores, the star begins its decent into oblivion. The star comes crashing in upon itself as it has no way to stave off gravity’s relentless grip, crushing the subsequent layers of left over elements from its lifetime. This inward free-fall is met at a certain size with an impossible force to breach; a neutron degeneracy pressure that forces the star to rebound outwards. This massive amount of gravitational and kinetic energy races back out with a fury that illuminates the universe, outshining entire galaxies in an instant. This fury is the life-blood of the cosmos; the drum beats in the symphony galactic, as this intense energy allows for the fusion of elements heavier than iron, all the way to uranium. These new elements are blasted outwards by this amazing force, riding the waves of energy that casts them deep into the cosmos, seeding the universe with all the elements that we know of.
Artistic impression of a star going supernova, casting its chemically enriched contents into the universe. These new elements are blasted outwards by this amazing force, riding the waves of energy that casts them deep into the cosmos, seeding the universe with all the elements that we know of. Credit: NASA/Swift/Skyworks Digital/Dana Berryto
But what is left? What is there after this spectacular event? That all depends again on the mass of the star. As mentioned earlier, the two forms that a dead massive star takes are either a Neutron Star or a Black Hole. For a Neutron Star, the formation is quite complex. Essentially, the events that I described occurs, except after the supernovae all that is left is a ball of degenerate neutrons. Degenerate is simply a term we apply to a form that matter takes on when it is compressed to the limits allowed by physics. Something that is degenerate is intensely dense, and this holds very true for a neutron star. A number you may have heard tossed around is that a teaspoon of neutron star material would weigh roughly 10 million tons, and have an escape velocity (the speed needed to get away from its gravitational pull) at about .4c, or 40% the speed of light. Sometimes the neutron star is left spinning at incredible velocities, and we label these as pulsars; the name derived from how we detect them.
A pulsar with its magnetic field lines illustrated. The beams emitting from the poles are what washes over our detectors as the dead star spins.
These types of stars generate a LOT of radiation. Neutron stars have an enormous magnetic field. This field accelerates electrons in their stellar atmospheres to incredible velocities. These electrons follow the magnetic field lines of the neutron star to its poles, where they can release radio waves, X-Rays, and gamma rays (depending on what type of neutron star it is). Since this energy is being concentrated to the poles, it creates a sort of lighthouse effect with high energy beams acting like the beams of light out of a lighthouse. As the star rotates, these beams sweep around many times per second. If the Earth, and thus our observation equipment, happens to be oriented favorably with this pulsar, we will register these “pulses” of energy as the stars’ beams wash over us. For all the pulsars we know about, we are much too far away for these beams of energy to hurt us. But if we were close to one of these dead stars, this radiation washing over our planet continuously would spell certain extinction for life as we know it.
What of the other form that a dead star takes; a black hole? How does this occur? If degenerate material is as far as we can crush matter, how does a black hole appear? Simply put, black holes are the result of an unimaginably large star and thus a truly massive amount of matter that is able to “break” this neutron degeneracy pressure upon collapse. The star essentially falls inward with such force that it breaches this seemingly physical limit, turning in upon itself and wrapping up spacetime into a point of infinite density; a singularity. This amazing event occurs when a star has roughly 18x the amount of mass that our sun has, and when it dies, it is truly the epitome of physics gone to the extreme. This “extra bit of mass” is what allows it to collapse this ball of degenerate neutrons and fall towards infinity. It is both terrifying and beautiful to think about; a point in spacetime that is not entirely understood by our physics, and yet something that we know exists. The truly remarkable thing about black holes is that it is like the universe working against us. The information we need to fully understand the processes within a black hole are locked behind a veil that we call the event horizon. This is the point of no return for a black hole, for which anything beyond this point in spacetime has no future paths that lead out of it. Nothing escapes at this distance from the collapsed star at its core, not even light, and thus no information ever leaves this boundary (at least not in a form we can use). The dark heart of this truly astounding object leaves a lot to be desired, and tempts us to cross into its realm in order to try and know the unknowable; to grasp the fruit from the tree of knowledge.
A black hole is the final form a massive star collapses to. The light (and spacetime itself) is warped around the black hole’s event horizon due to extreme gravitational effects. This is as accurate as we can be to visualizing an actual black hole as it was generated with a code that implemented General Relativity accurately. Credit and Copyright: Paramount Pictures/Warner Bros. From “Interstellar” the film. Mathematical model used to create the image developed by Dr. Kip Thorne
Now it must be said, there is much in the way of research with black holes to this day. Physicists such as Professor Stephen Hawking, among others, have been working tirelessly on the theoretical physics behind how a black hole operates, attempting to solve the paradoxes that frequently appear when we try to utilize the best of our physics against them. There are many articles and papers on such research and their subsequent findings, so I will not dive into their intricacies for both wishing to preserve simplicity in understanding, and to also not take away from the amazing minds that are working these issues. Many suggest that the singularity is a mathematical curiosity that does not completely represent what physically happens. That the matter inside an event horizon can take on new and exotic forms. It is also worth noting that in General Relativity, anything with mass can collapse to a black hole, but we generally hold to a range of masses as creating a black hole with anything less than is in that mass range is beyond our understanding of how that could happen. But as someone who studies physics, I would be remiss to not mention that as of now, we are at an interesting cross section of ideas that deal very intimately with what is actually going on within these specters of gravity.
All of this brings me back to a point that needs to be made. A fact that needs to be recognized. As I described the deaths of these massive stars, I touched on something that occurs. As the star is being ripped apart from its own energy and its contents being blown outwards into the universe, something called nucleosynthesis is occurring. This is the fusion of elements to create new elements. From hydrogen up to uranium. These new elements are being blasted outwards an incredible speeds, and thus all of these elements will eventually find their way into molecular clouds. Molecular clouds (Dark Nebulae) are the stellar nurseries of the cosmos. This is where stars begin. And from star formation, we get planetary formation.
Planets coalescing out of the remaining molecular cloud the star formed out of. Within this accretion disk lay the fundamental elements necessary for planet formation and potential life. Credit: NASA/JPL-Caltech/T. Pyle (SSC) – February, 2005
As a star forms, a cloud of debris that is made up of the molecular cloud that birthed said star begins to spin around it. This cloud, as we now know, contains all those elements that were cooked up in our supernovae. The carbon, the oxygen, the silicates, the silver, the gold; all present in this cloud. This accretion disk about this new star is where planets form, coalescing out of this enriched environment. Balls of rock and ice colliding, accreting, being torn apart and then reformed as gravity works its diligent hands to mold these new worlds into islands of possibility. These planets are formed from those very same elements that were synthesized in that cataclysmic eruption. These new worlds contain the blueprints for life as we know it.
Upon one of these worlds, a certain mixture of hydrogen and oxygen occurs. Within this mixture, certain carbon atoms form up to create replicating chains that follow a simple pattern. Perhaps after billions of years, these same elements that were thrust into the universe by that dying star finds itself giving life to something that can look up and appreciate the majesty that is the cosmos. Perhaps that something has the intelligence to realize that the carbon atom within it is the very same carbon atom that was created in a dying star, and that a supernovae occurred that allowed that carbon atom to find its way into the right part of the universe at the right time. The energy that was the last dying breath of a long dead star was the same energy that allowed life to take its first breath and gaze upon the stars. These stellar ghosts are our ancestors. They are gone in form, but yet remain within our chemical memory. They exist within us. We are supernova. We are star dust. We are descended from stellar ghosts…
We are awash in the light from long dead stars, each contributing essential ingredients to the universe that are necessary for life. Image Credit: Hubble
The Soyuz MS-01 spacecraft preparing to launch from the Baikonur Cosmodrome, in Kazakhstan, on Monday, July 4th, 2016. Credit: (NASA/Bill Ingalls)
On Saturday, September 17th, the Russian space agency (Roscosmos) stated that it would be delaying the launch of the crewed spacecraft Soyuz MS-02. The rocket was scheduled to launch on Friday, September 23rd, and would be carrying a crew of three astronauts – two Russia and one American – to the ISS.
After testing revealed technical flaws in the mission (which were apparently due to a short circuit), Rocosmos decided to postpone the launch indefinitely. But after after days of looking over the glitch, the Russians space agency has announced that it is prepared for a renewed launch on Nov. 1st.
The mission crew consists of mission commander Sergey Ryzhikov, flight engineer Andrey Borisenko and NASA astronaut Shane Kimbrough. Originally scheduled to launch on Sept. 23rd, the mission would spend the next two days conducting a rendezvous operation before docking with the International Space Station on Sept. 25th.
The crew of MS-02 (from left to right): Shane Kimgrough, Sergey Ryzhikov and Andrey Borisenko, pictured in Red Square in Moscow. Credit: NASA/Bill Ingalls
The station is currently being staffed by three crew members – MS-01 commander Anatoly Ivanishin, NASA astronaut Kate Rubins and Japanese astronaut Takuya Onish. These astronauts arrived on the station on Sept.6th, and all three were originally scheduled to return to Earth on October 30th.
Meanwhile, three more astronauts – commander Oleg Novitskiy, ESA flight engineer Thomas Pesquet and NASA astronaut Peggy Whitson – were supposed to replace them as part of mission MS-03, which was scheduled to launch on Nov. 15th. But thanks to the technical issue that grounded the MS-02 flight, this schedule appeared to be in question.
However, the news quickly began to improve after it seemed that the mission might be delayed indefinitely. On Sept.18th, a day after the announcement of the delay, the Russian International News Agency (RIA Novosti) cited a source that indicated that the spacecraft could be replaced and the mission could be rescheduled for next month:
“RIA Novosti’s source noted that the mission was postponed indefinitely because of an identified short circuit during the pre-launch checks. It is possible that the faulty ship “MS – 02 Alliance” can be quickly replaced on the existing same rocket, and then the launch to the ISS will be held in late October.”
Three newly arrived crew of Expedition 48 in Soyuz MS-01 open the hatch and enter the International Space Station after docking on July 9, 2016. Credit: NASA TV
Then, on Monday, Sept.19th, another source cited by RIA Novosti said that the State Commission responsible for the approval of a new launch date would be reaching a decision no sooner than Tuesday, Sept. 20th. And as of Tuesday morning, a new launch date appears to have been set.
According to news agency, Roscomos notified NASA this morning that the mission will launch on Nov.1st. Sputnik International confirmed this story, claiming that the source was none other than Alexander Koptev – a NASA representative with the Russian Mission Control Center.
“The Russian side has informed the NASA central office of the preliminary plans to launch the manned Soyuz MS-02 on November 1,” he said.
It still not clear where the technical malfunction took place. Since this past Saturday, Russian engineers have been trying to ascertain if the short circuit occurred in the descent module or the instrument module. However, the Russians are already prepared to substitute the Soyuz spacecraft for the next launch, so there will be plenty of time to locate the source of the problem.
The Soyuz MS-01 spacecraft launches from the Baikonur Cosmodrome on July 7th, 2016. Credit: NASA/Bill
The Soyuz MS is the latest in a long line of revisions to the venerable Soyuz spacecraft, which has been in service with the Russians since the 1960s. It is perhaps the last revision as well, as Roscosmos plans to develop new crewed spacecraft in the coming decades.
The MS is an evolution of the Soyuz TMA-M spacecraft, another modernized version of the old spacecraft. Compared to its predecessor, the MS model’s comes with updated communications and navigation subsystems, but also boasts some thruster replacements.
The first launch of the new spacecraft – Soyuz MS-01 – took place on July 7th, 2016, aboard a Soyuz-FG launch vehicle, which is itself an improvement on the traditional R-7 rockets. Like the MS-02 mission, MS-01 spent two days undergoing a checkout phase in space before rendezvousing with the ISS.
As such, it is understandable why the Russians would like to get this mission underway and ensure that the latest iteration of the Soyuz MS performs well in space. Until such time as the Russians have a new crewed module to deliver astronauts to the ISS, all foreseeable missions will come down to craft like this one.
A scene from ‘Destination Mars’ of Buzz Aldrin and NASA’s Curiosity Mars rover with the Gale crater rim in the distance. The new, limited time interactive exhibit is now showing at the Kennedy Space Center visitor complex in Florida through Jan 1, 2017. Credit: NASA/JPL/Microsoft
A scene from ‘Destination Mars’ of Buzz Aldrin and NASA’s Curiosity Mars rover with the Gale crater rim in the distance. The new, limited time interactive exhibit is now showing at the Kennedy Space Center visitor complex in Florida through Jan 1, 2017. Credit: NASA/JPL/Microsoft
KENNEDY SPACE CENTER VISITOR COMPLEX, FL- Think a Holodeck adventure on Star Trek guided by real life Apollo 11 moonwalker Buzz Aldrin and you’ll get a really good idea of what’s in store for you as you explore the surface of Mars like never before in the immersive new ‘Destination Mars’ interactive holographic exhibit opening to the public today, Monday, Sept.19, at the Kennedy Space Center visitor complex in Florida.
The new Red Planet exhibit was formally opened for business during a very special ribbon cutting ceremony featuring Buzz Aldrin as the star attraction – deftly maneuvering the huge ceremonial scissors during an in depth media preview and briefing on Sunday, Sept. 18, 2016, including Universe Today.
The fabulous new ‘Destination Mars’ limited engagement exhibit magically transports you to the surface of the Red Planet via Microsoft HoloLens technology.
It literally allows you to ‘Walk on Mars’ using real imagery taken by NASA’s Mars Curiosity rover and explore the alien terrain, just like real life scientists on a geology research expedition.
A ceremonial ribbon is cut for the opening of new “Destination: Mars” experience at the Kennedy Space Center visitor complex in Florida during media preview on Sept. 18, 2016. From the left are Therrin Protze, chief operating officer of the visitor complex; center director Bob Cabana; Apollo 11 astronaut Buzz Aldrin; Kudo Tsunoda of Microsoft; and Jeff Norris of NASA’s Jet Propulsion Laboratory in Pasadena, California. Credit: Ken Kremer/kenkremer.com
“Technology like HoloLens leads us once again toward exploration,” Aldrin said during the Sept. 18 media preview. “It’s my hope that experiences like “Destination: Mars” will continue to inspire us to explore.”
Destination Mars was jointly developed by NASA’s Jet Propulsion Laboratory – which manages the Curiosity rover mission for NASA – and Microsoft HoloLens.
A ceremonial ribbon is cut for the opening of new “Destination: Mars” experience at the Kennedy Space Center visitor complex in Florida during media preview on Sept. 18, 2016. From the left are Therrin Protze, chief operating officer of the visitor complex; center director Bob Cabana; Apollo 11 astronaut Buzz Aldrin; Kudo Tsunoda of Microsoft; and Jeff Norris of NASA’s Jet Propulsion Laboratory in Pasadena, California. Credit: Dawn Taylor Leek
Buzz was ably assisted at the grand ribbon cutting ceremony by Bob Cabana, former shuttle commander and current Kennedy Space Center Director, Therrin Protze, chief operating officer of the visitor complex, Kudo Tsunoda of Microsoft, and Jeff Norris of NASA’s Jet Propulsion Laboratory in Pasadena, California.
The experience is housed in a pop-up theater that only runs for the next three and a half months, until New Years Day, January 1, 2017.
Before entering the theater, you will be fitted with specially adjusted HoloLens headsets individually tailored to your eyes.
The entire ‘Destination Mars’ experience only lasts barely 8 minutes.
So, if you are lucky enough to get a ticket inside you’ll need to take advantage of every precious second to scan around from left and right and back, and top to bottom. Be sure to check out Mount Sharp and the rim of Gale Crater.
You’ll even be able to find a real drill hole that Curiosity bored into the Red Planet at Yellowknife Bay about six months after the nailbiting landing in August 2012.
During your experience you will be guided by Buzz and Curiosity rover driver Erisa Hines of JPL. They will lead you to areas of Mars where the science team has made many breakthrough discoveries such as that liquid water once flowed on the floor of Curiosity’s Gale Crater landing site.
Curiosity rover driver Erisa Hines and Jeff Norris of NASA’s Jet Propulsion Laboratory at the grand opening for Destination Mars at the Kennedy Space Center visitor complex in Florida on Sept. 18, 2016. Credit Julian Leek
The scenes come to life based on imagery combining the Mastcam color cameras and the black and white navcam cameras, Jeff Norris of NASA’s Jet Propulsion Laboratory in Pasadena, California, told Universe Today in an interview.
Among the surface features visited is Yellowknife Bay where Curiosity conducted the first interplanetary drilling and sampling on another planet in our Solar System. The sample were subsequently fed to and analyzed by the pair of miniaturized chemistry labs – SAM and CheMin – inside the rovers belly.
They also guide viewers to “a tantalizing glimpse of a future Martian colony.”
“The technology that accomplishes this is called “mixed reality,” where virtual elements are merged with the user’s actual environment, creating a world in which real and virtual objects can interact, “ according to a NASA description.
“The public experience developed out of a JPL-designed tool called OnSight. Using the HoloLens headset, scientists across the world can explore geographic features on Mars and even plan future routes for the Curiosity rover.”
Curiosity is currently exploring the spectacular looking buttes in the Murray Buttes region in lower Mount Sharp. Read my recent update here.
A scene from ‘Destination Mars’ of Erisa Hines and NASA’s Curiosity Mars rover with Mount Sharp Gale crater rim in the distance. The new, limited time interactive exhibit is now showing at the Kennedy Space Center visitor complex in Florida through Jan 1, 2017. Credit: NASA/JPL/Microsoft
Be sure to pay attention or your discovery walk on Mars will be over before you know it. Personally, as a Mars lover and Mars mosaic maker I was thrilled by the 3 D reality and I was ready for more.
Curiosity accomplished Historic 1st drilling into Martian rock at John Klein outcrop on Feb 8, 2013 (Sol 182) and discovered a habitable zone, shown in this context mosaic view of the Yellowknife Bay basin taken on Jan. 26 (Sol 169). The robotic arm is pressing down on the surface at John Klein outcrop of veined hydrated minerals – dramatically back dropped with her ultimate destination; Mount Sharp. Credit: NASA/JPL-Caltech/Ken Kremer-kenkremer.com/Marco Di Lorenzo
This limited availability, timed experience is available on a first-come, first-served basis. Reservations must be made the day of your visite at the Destination: Mars reservation counter, says the KSC Visitor Complex (KSCVC).
You can get more information or book a visit to Kennedy Space Center Visitor Complex, by clicking on the website link:
Be sure to visit this spectacular holographic exhibit before it closes on New Year’s Day 2017 because it is only showing at KSCVC.
There are no plans to book it at other venues, Norris told me.
Apollo 11 moonwalker Buzz Aldrin describes newly opened ‘Destination Mars’ holographic experience during media preview at the Kennedy Space Center visitor complex in Florida on Sept. 18, 2016. Credit: Ken Kremer/kenkremer.com
As of today, Sol 1465, September 19, 2016, Curiosity has driven over 7.9 miles (12.7 kilometers) since its August 2012 landing inside Gale Crater, and taken over 354,000 amazing images.
Apollo 11 moonwalker Buzz Aldrin during media preview of newly opened ‘Destination Mars’ holographic experience at the Kennedy Space Center visitor complex in Florida on Sept. 18, 2016. Credit Julian Leek
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
I’ve got to say, you are one of the luckiest people I’ve ever met.
For starters, you are the descendant of an incomprehensible number of lifeforms who were successful, and survived long enough to find a partner, procreate, and have an offspring. Billions of years, and you are the result of an unbroken chain of success, surviving through global catastrophe after catastrophe. Nice going.
Not only that, but your lineage happened to be born on a planet, which was in just the right location around just the right kind of star. Not too hot, not too cold, just the right temperature where liquid water, and whatever else was necessary for life to get going. Again, I like your lucky streak.
Yup, you are pretty lucky to call this place home. Credit: NASA
In fact, you happened to be born into a Universe that has the right physical constants, like the force of gravity or the binding force of atoms, so that stars, planets and even the chemistry of life could happen at all.
But there’s another lottery you won, and you probably didn’t even know about it. You happened to be born on an unassuming, mostly harmless planet orbiting a G-type main sequence star in the habitable zone of the Milky Way.
Wait a second, even galaxies have habitable zones? Yep, and you’re in it right now.
The Milky Way is a big place, measuring up to 180,000 light years across. It contains 100 to 400 billion stars spread across this enormous volume.
We’re located about 27,000 light years away from the center of the Milky Way, and tens of thousands of light-years away from the outer rim.
Credit: ESA
The Milky Way has some really uninhabitable zones. Down near the center of the galaxy, the density of stars is much greater. And these stars are blasting out a combined radiation that would make it much more unlikely for life to evolve.
Radiation is bad for life. But it gets worse. There’s a huge cloud of comets around the Sun known as the Oort Cloud. Some of the greatest catastrophes in history happened when these comets were kicked into a collision course with the Earth by a passing star. Closer to the galactic core, these disruptions would happen much more often.
There’s another dangerous place you don’t want to be: the galaxy’s spiral arms. These are regions of increased density in the galaxy, where star formation is much more common. And newly forming stars blast out dangerous radiation.
Fortunately, we’re far away from the spiral arms, and we orbit the center of the Milky Way in a nice circular orbit, which means we don’t cross these spiral arms very often.
We stay nice and far away from the dangerous parts of the Milky Way, however, we’re still close enough to the action that our Solar System gathered the elements we needed for life.
The first stars in the Universe only had hydrogen, helium and a few other trace elements left over from the Big Bang. But when the largest stars detonated as supernovae, they seeded the surrounding regions with heavier elements like oxygen, carbon, even iron and gold.
Early stars were made almost entirely of hydrogen and helium. Credit: NASA/WMAP Science Team
Our solar nebula was seeded with the heavy elements from many generations of stars, giving us all the raw materials to help set evolution in motion.
If the Solar System was further out, we probably wouldn’t have gotten enough of those heavier elements. So, thanks multiple generations of dead stars.
According to astrobiologists the galactic habitable zone probably starts just outside the galactic bulge – about 13,000 light-years from the center, and ends about halfway out in the disk, 33,000 light-years from the center.
Remember, we’re 27,000 light-years from the center, so just inside that outer edge. Phew.
The Milky Way’s habitable zone. Credit: NASA/Caltech
Of course, not all astronomers believe in this Rare Earth hypothesis. In fact, just as we’re finding life on Earth wherever we find water, they believe that life is more robust and resilient. It could still survive and even thrive with more radiation, and less heavier elements.
Furthermore, we’re learning that solar systems might be able to migrate a significant distance from where they formed. Stars that started closer in where there were plenty of heavier elements might have drifted outward to the safer, calmer galactic suburbs, giving life a better chance at getting a foothold.
As always, we’ll need more data, more research to get an answer to this question.
Just when you thought you were already lucky, it turns out you were super duper extra lucky. Right Universe, right lineage, right solar system, right location in the Milky Way. You already won the greatest lottery in existence.
Ahuna Mons towers over the Cerean landscape in this photo taken by the Dawn spacecraft. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI
Whoa – what a sight! Ceres’ lonely mountain, Ahuna Mons, is seen in this simulated perspective view. The elevation has been exaggerated by a factor of two. The view was made using enhanced-color images from NASA’s Dawn mission in August from an altitude of 240 miles (385 km) in August 2016. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI
An isolated 3-mile-high (5 km) mountain Ahuna Mons on Ceres is likely volcanic in origin, and the dwarf planet may have a weak, temporary atmosphere. These are just two of many new insights about Ceres from NASA’s Dawn mission published this week in six papers in the journal Science.
Ahuna Mons is seen in this mosaic of images from NASA’s Dawn spacecraft. On its steepest side, this mountain is about 3 miles (5 km) high. Its average overall height is 2.5 miles (4 km). The diameter of the mountain is about 12 miles (20 km). Dawn took these images from its low-altitude mapping orbit, 240 miles (385 kilometers) above the surface, in December 2015. Credits: NASA/JPL/Dawn mission
“Dawn has revealed that Ceres is a diverse world that clearly had geological activity in its recent past,” said Chris Russell, principal investigator of the Dawn mission, based at the University of California, Los Angeles.
The Ahuna Mons dome compared to a dome in Russia. The similarity in appearance is striking though the difference in size is large. Credit: NASA
Ahuna Mons is a volcanic dome similar to earthly and lunar volcanic domes but unique in the solar system, according to a new analysis led by Ottaviano Ruesch of NASA’s Goddard Space Flight Center and the Universities Space Research Association. While those on Earth erupt with molten rock, Ceres’ grandest peak likely formed as a salty-mud volcano. Instead of molten rock, salty-mud volcanoes, or “cryovolcanoes,” release frigid, salty water sometimes mixed with mud.
Learn more about Ahuna Mons
“This is the only known example of a cryovolcano that potentially formed from a salty mud mix, and that formed in the geologically recent past,” Ruesch said. Estimates place the mountain formation within the past billion years.
Dawn may also have detected a weak, temporary atmosphere; the probe’s gamma ray and neutron (GRaND) detector observed evidence that Ceres had accelerated electrons from the solar wind to very high energies over a period of about six days. In theory, the interaction between the solar wind’s energetic particles and atmospheric molecules could explain the GRaND observations.
Dwarf planet Ceres is located in the asteroid belt, between the orbits of Mars and Jupiter. Observations by ESA’s Herschel Space Observatory between 2011 and 2013 found that the dwarf planet has a thin water-vapor atmosphere, the first detection ever of water vapor around an asteroid in the asteroid belt. Copyright ESA/ATG medialab/Küppers et al.
A temporary atmosphere would confirm the water vapor the Herschel Space Observatory detected at Ceres in 2012-2013. The electrons that GRaND detected could have been produced by the solar wind hitting the water molecules that Herschel observed, but scientists are also looking into alternative explanations.
While Ahuna Mons may have erupted liquid water in the not-too-distant past, Dawn found probable water ice right now in the mid-latitude Oxo Crater using its visible and infrared mapping spectrometer (VIR).
The small, bright crater Oxo (6 miles / 10 km wide) on Ceres is seen in this perspective view. The elevation has been exaggerated by a factor of two. The view was made using enhanced-color images from NASA’s Dawn mission. Dawn’s visible and infrared mapping spectrometer (VIR) has found evidence of water ice at this crater. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Exposed water-ice is rare on the dwarf planet, but the low density of Ceres — 2.08 grams/cm3 vs. 5.5 for Earth — the impact-generated ice detection and the the existence of Ahuna Mons suggest that Ceres’ crust does contain a significant amount of water ice.
Impact craters are clearly the most abundant geological feature on Ceres, and their different shapes help tell the complex story of Ceres’ past. Craters that are roughly polygonal — shapes bounded by straight lines — hint that Ceres’ crust is heavily fractured. In addition, several Cerean craters display fractures on their floors. There are craters with flow-like features. Bright areas are peppered across Ceres, with the most reflective ones in Occator Crater. Some crater shapes could indicate water-ice in the subsurface.
In this illustration, a mud slurry rises up through Ceres’ crust to build a dome like Ahuna Mons. Click to see the animation. Credit: Goddard Media Studios
All these crater forms imply an outer shell for Ceres that is not purely ice or rock, but rather a mixture of both. Scientists also calculated the ratio of various craters’ depths to diameters, and found that some amount of crater relaxation must have occurred as icy walls gradually slump.
“The uneven distribution of craters indicates that the crust is not uniform, and that Ceres has gone through a complex geological evolution,” Hiesinger said.
The rim of Hamori Crater on Ceres is seen in the upper left portion of this image, which was taken by NASA’s Dawn spacecraft. Clay is found at many locations on the dwarf planet. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Ceres’ crust also appears loaded with clay-forming minerals called phyllosilicates. These phyllosilicates are rich in magnesium and also have some ammonium embedded in their crystalline structure. Their distribution throughout the dwarf planet’s crust indicates Ceres’ surface material has been altered by a global process involving water.
Now in its extended mission, the Dawn spacecraft has been increasing its altitude since Sept. 2 as scientists stand back once again for a broader look at Ceres under different lighting conditions now compared to earlier in the mission.
A tornado near Anadarko, Oklahoma. Credit: NSSL/NOAA
Tornadoes are a fascinating force of nature, as awe-inspiring as they are destructive. They form periodically due to the convergence of weather patterns, and often leave plenty of devastation in their wake. And for those who live in the active tornado regions of the world, they are an unfortunate fact of life.
Such is the nature of life for those who live in the infamous “Tornado Alley”, a region that extends from the southern US into parts of Canada. This area is so-named because of the frequency with which tornadoes take place. Compared to other active regions of the world, this area experiences the highest frequency of violent tornadoes.
Origin of the Name:
The term “Tornado Alley” was first used in 1952 as the title of a research project about severe weather in the US. This project was conducted by U.S. Air Force meteorologists Maj. Ernest J. Fawbush and Capt. Robert C. Miller, and covered a region extending from areas of Texas to locations throughout the mid-western US.
Tornado at Union City, Oklahoma. Credit: NOAA Photo Library
The term has since caught on thanks to media sources as well meteorologist and climatologists, though many use the term “Great Plains Tornado Belt” as well.
Geographical Area:
The geographical boundaries of “Tornado Alley” have never been very clearly defined and no official definition has been adopted by the National Weather Service (NWS). As a result, different definitions and boundaries have been adopted based on different sets of criteria. For instance, the National Severe Storms Laboratory (NSSL) states:
“‘Tornado Alley’ is just a nickname made up by the media for an area of relatively high tornado occurrence; it is not a clearly defined area. Is tornado alley the area with the most violent tornadoes, or is it the area with the most tornado-related deaths, or the highest frequency or tornadoes? It depends on what kind of information you want!”
While no region of the US is entirely free of tornadoes, they occur more frequently in the mid-western US – spanning areas of Texas to parts of Oklahoma, Kansas, South Dakota, Iowa, Illinois, Missouri, New Mexico, Colorado, North Dakota, and Minnesota.
Artist’s impression of the geographical region known as “Tornado Alley”. Credit: Dan Craggs/Wikipedia Commons
Texas reports the most tornadoes of any state, whereas Kansas and Oklahoma rank first and second respectively in the number of tornadoes per area. Florida also reports a high number and density of tornado occurrences, though tornadoes there rarely reach the strength of those that sometimes occur in the southern plains.
However, the Canadian prairies, eastern Colorado and western Pennsylvania are often included in the boundaries. And last, several smaller areas have been designated as being their own “Tornado Alley” – which include the Texas/Oklahoma/Kansas core, the Upper Midwest, the lower Ohio Valley, the Tennessee Valley and the lower Mississippi valley.
There is also the term “Dixie Alley”, a name coined by Allen Peasons, a former director of the National Severe Storms Forecasting Center (NSSFC), in 1971. This name refers to the lower Mississippi Valley and upper Tennessee Valley were tornadoes occur frequently.
Nevertheless, most definitions focus on the geographical region known as the Great Plains where no major mountain ranges are located. This is important because mountains act as breaks on weather systems, forcing them to dump the majority of their moisture before crossing over them (the reason why the southwestern US has a more arid climate).
Image from Federal Emergency Management Agency booklet, “Taking Shelter from the Storm: Building a Safe Room Inside your House” (3rd ed.). Credit: FEMA
In the case of the Great Plains, the region’s lack of these natural barriers leaves it open to cold fronts from Canada and warm fronts from Mexico and the Gulf Coast. When cold and warm front collide, they create supercells and thunderstorm systems that lead to tornadoes.
Impact:
Due to the frequency of tornadoes in certain areas of the United States, building codes and warning systems have been implemented. These include the institution of special building codes, construction of storm cellars, sirens, preparedness drills, education programs, and regular weather coverage by local media outlets.
According to the National Climatic Data Center, during the period of 1991 to 2010, those states that have the most experienced an average of 5.7 (Minnesota) to 12.2 (Florida) tornadoes. Using a long-term average (based on data collected between 1950 and 2012), the entire “Alley” experiences about 268 tornadoes per year.
In the southeastern United States, where housing is less robust and many people live in mobile homes, causalities are particularly high. According to the NOAA, almost 3600 tornadoes have occurred in the United States, which resulted in more than 20,000 deaths, between 1680 and 2000.
The track of the tornado that struck Moore, Oklahoma on May 20, 2013 is visible from space in this false color image taken on June 2, 2013 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite.
Meanwhile, data from the Tornado History Project shows there were 5,587 confirmed fatalities blamed on tornadoes across the United States between 1950 and 2012. Of those, 1,110 occurred in Tornado Alley. The injuries caused by tornadoes are much higher, with a reported 64,054 injuries being attributed to tornadoes during the same period – over 15,000 of which occurred in Tornado Alley.
The worst year on record was 2011, when tornado activity spiked leading to 1,704 confirmed tornadoes and 553 confirmed deaths. This includes the 158 deaths that resulted from the tornado that struck Joplin, Missouri, on May 22nd, which was also the deadliest since modern record-keeping began in 1950.
In financial terms, the cost of tornadoes is also quite high. In fact, the Insurance Information Institute reports that between 1993 and 2012, the average insured loss per year was $7.78 billion for severe thunderstorm events, including tornadoes. In 2011, during the spike in storms, an estimated $27 billion was filed for in insurance claims.
No matter how you slice it, living in regions where tornadoes are known to frequent is both a dangerous and expensive prospect. As our understanding of tornadoes grows, we are able to predict where they will form and what paths they will take with greater accuracy. As such, we can reduce the cost in human and monetary terms over time.
Satellite image showing the after-effects of the deadly tornado that ripped through Indiana and Kentucky. Credit: NASA Landsat Project Science Office and USGS EROS
But in the long run, the greatest safeguards against injuries and death are public awareness and education. Tornadoes are also an important aspect of Climate Change, since changes in our environment are likely to effect and exacerbate extreme weather patterns.
The Earth's layers, showing the Inner and Outer Core, the Mantle, and Crust. Credit: discovermagazine.com
As you may recall learning in geology class, the Earth is made up of distinct layers. The further one goes towards the center of the planet, the more intense the heat and pressure becomes. Luckily, for those of us living on the crust (the outermost layer, where all life lives) the temperature is relatively steady and pleasant.
In fact, one of the things that makes planet Earth habitable is the fact that the planet is close enough to our Sun to receive enough energy to stay warm. What’s more, its “surface temperatures” are warm enough to sustain liquid water, the key to life as we know it. But the temperature of Earth’s crust also varies considerably depending on where and when you are measuring it.
Earth’s Structure:
As a terrestrial planet, Earth is composed of silicate rocks and metals which are differentiated between a solid metal core, a molten outer core, and a silicate mantle and crust. The inner core has an estimated radius of 1,220 km, while the outer core extends beyond it to a radius of about 3,400 km.
The layers of the Earth, a differentiated planetary body. Credit: Wikipedia Commons/Surachit
Extending outwards from the core are the mantle and the crust. Earth’s mantle extends to a depth of 2,890 km beneath the surface, making it the thickest layer of Earth. This layer is composed of silicate rocks that are rich in iron and magnesium relative to the overlying crust. Although solid, the high temperatures within the mantle cause the silicate material to be sufficiently ductile that it can flow on very long timescales.
The upper layer of the mantle is divided into the lithospheric mantle (aka. the lithosphere) and the asthenosphere. The former consists of the crust and the cold, rigid, top part of the upper mantle (which the tectonic plates are composed of) while the asthenosphere is the relatively low-viscosity layer on which the lithosphere rides.
Earth’s Crust:
The crust is the absolute outermost layer of the Earth, which constitutes just 1% of the Earth’s total mass. The thickness of the crust varies depending on where the measurements are taken, ranging from 30 km thick where there are continents to just 5 km thick beneath the oceans.
The crust is composed of a variety of igneous, metamorphic and sedimentary rocks and is arranged in a series of tectonic plates. These plates float above the Earth’s mantle, and it’s believed that convection in the mantle causes the plates to be in constant motion.
Sometimes these plates collide, pull apart, or slide alongside each other; resulting in convergent boundaries, divergent boundaries, and transform boundaries. In the case of convergent boundaries, subduction zones are often the result, where the heavier plate slips under the lighter plate – forming a deep trench.
In the case of divergent boundaries, these are formed when tectonic plates pull apart, forming rift valleys on the seafloor. When this happens, magma wells up in the rift as the old crust pulls itself in opposite directions, where it is cooled by seawater to form new crust.
A transform boundary is formed when tectonic plates slide horizontally and parts get stuck at points of contact. Stress builds in these areas as the rest of the plates continue to move, which causes the rock to break or slip, suddenly lurching the plates forward and causing earthquakes. These areas of breakage or slippage are called faults.
Illustration of the Earth’s Tectonic Plates and the plate boundaries. Credit: msnucleus.org
Taken together, these three types of tectonic plate action are what is responsible for shaping the Earth’s crust and leading to periodic renewal of its surface over the course of millions of years.
Temperature Range:
The temperature of the Earth’s crust ranges considerably. At its outer edge, where it meets the atmosphere, the crust’s temperature is the same temperature as that of the air. So, it might be as hot as 35 °C in the desert and below freezing in Antarctica. On average, the surface of the Earth’s crust experiences temperatures of about 14°C.
However, the hottest temperature ever recorded was 70.7°C (159°F), which was taken in the Lut Desert of Iran as part of a global temperature survey conducted by scientists at NASA’s Earth Observatory. Meanwhile, the coldest temperature ever recorded on Earth was measured at the Soviet Vostok Station on the Antarctic Plateau – which reached an historic low of -89.2°C (-129°F) on July 21st, 1983.
That’s quite the range already. But consider the fact that the majority of the Earth’s crust lies beneath the oceans. Far from the Sun, temperatures can reach as low as 0-3° C (32-37.5° F) where the water reaches the crust. Still, a lot balmier than a cold night in Antarctica!
And as geologists have known for some time, if you dig down into the continental crust, temperatures will go up. For example, the deepest mine in the world is currently the TauTona gold mine in South Africa, measuring 3.9 km deep. At the bottom of the mine, temperatures reach a sweltering 55 °C, which requires that air conditioning be provided so that it’s comfortable for the miners to work all day.
So in the end, the temperature of Earth’s crust varies considerably. It’s average surface temperature which depends on whether it is being taken on dry land or beneath the sea. And depending on the location, seasons, and time of day, it can range from sweltering to freezing cold!
And yet, Earth’s crust remains the only place in the Solar System where temperatures are stable enough that life can continue to thrive on it. Add to that our viable atmosphere and protective magnetosphere, and we really should consider ourselves to be the lucky ones!
