Earth’s Shield! A Natural Barrier in Space

Have you ever heard of the Van Allen belts? If not you really should learn about them.  After all, without them the majority of life on Earth could not survive.

So what are they and how do they keep us alive?

The Van Allen Belts are a collection of charged particles, held in place by the magnetic field of Earth, that act as a barrier to prevent the most harmful radiation from the Sun from reaching the surface of the Earth.  They shift according to the incoming energy of the Sun, and if there is a large enough swell of solar energy, satellites in Earth orbit can be dosed with high levels of radiation.  They were the first discovery by a man-made object in space, courtesy of US-borne Explorer 1 in 1958.

Credit: NASA/Goddard

The belts are entirely due to the magnetic field of the Earth, which results from the spinning liquid Nickel-Iron core of our planet.  If you want to know why look up Magnetic Induction in a College Physics text.  It’s not a complicated concept, but it is happening on a massive scale.  If we didn’t have a magnetic field, we would have no Van Allen belts, and would be fried by harmful solar radiation. The inner belt resides between 800 and 12,000 Km above the Earth, while the outer belt extends from 17,000 to 80,000 Km.  There is a gap in the belt locations, and we had no idea why, until now.

In August 2012, NASA launched the Van Allen probes, two identical spacecraft with elliptical orbits around Earth that take them through the belts.  Why two spacecraft? From NASA’s Van Allen Mission Overview:

“…a single moving spacecraft cannot discern whether any changes it observes are due to travelling disturbances, or if the spacecraft simply flew through two static, but differing, regions. Two spacecraft with identical instruments, however, can distinguish between these possibilities.”

NASA’s Van Allen probes. Credit: NASA/Goddard

The Van Allen probes found that within the gap between the two belts exists a drain that acts as a barrier against the highest-energy electrons.

“This barrier for the ultra-fast electrons is a remarkable feature of the belts,” said Dan Baker, a space scientist at the University of Colorado in Boulder and first author of the paper. “We’re able to study it for the first time, because we never had such accurate measurements of these high-energy electrons before.”

The area between the belts is known as the plasmasphere, containing a cloud of relatively cool charged particles.  The outer boundary of this region acts as a hard barrier that scatters incoming electrons and moves them into giant loops around the Earth.

“When you look at really energetic electrons, they can only come to within a certain distance from Earth,” said Shri Kanekal, the deputy mission scientist for the Van Allen Probes at NASA’s Goddard Space Flight Center in Greenbelt, Maryland and a co-author on the Nature paper. “This is completely new. We certainly didn’t expect that.”

This also explains why the solar-driven movement of the belts can result in satellites receiving high doses of radiation.  The looping electrons at the edge of the plasmasphere are pushed inward.

The video above is a NASA visualization showing the plasmasphere and it’s protection from incoming high energy particles.  Notice that the electrons are directed in loops along the plasmasphere, but they do not move closer to the Earth.

This gives us some insight into how Earth’s magnetic field protects us from harmful solar radiation.  Still there is a chance that a large enough solar flare could strip the belts away completely and still destroy us.  But a flare like that would have to be larger than any solar flare ever observed.  So hopefully that won’t happen.

Meteorites make rare Diamonds!

When a large meteorite collides with the Earth, it can be travelling upwards of 40 Kilometres per second.  This collision releases a huge amount of energy, which can vaporize rocks and create interesting and unique geological structures.

For decades, scientists have been debating the existence of a rare type of crystal called Lonsdaleite, which is associated with impacts.  Strange small crystals were discovered in Arizona in the 1950s around an ancient impact crater called ‘Canyon Diablo.’  It led some scientists to believe that the mineral had mechanical properties similar to diamond, but that it was structurally superior. If it existed in a pure form somewhere, it could have huge industrial applications.  Even though this led to a lot of interest in the crystal, it had never been found or synthesized outside of tiny crystals associated with impacts.

Diamond grains from the Canyon Diablo meteorite. The tick marks are spaced one-fifth of a millimeter (200 microns) apart. Credit: Arizona State University/Laurence Garvie

With new electron microscope technology, researchers from Arizona State University re-examined the tiny crystals and determined that the Lonsdaleite is actually the same as normal diamond, but with small impurities due to shock and heating associated with the impacts.

“Most crystals have regular repeating structures, much like the bricks in a well-built wall,” says Peter Buseck, a researcher with ASU’s School of Earth and Space exploration. “However, defects are intermixed with the normal diamond structure, just as if the wall had an occasional half-brick or longer brick or row of bricks that’s slightly displaced to one side or another.”

So it turns out there’s no super-diamond, but once again, science has solved a long standing mystery.

Sending Astronomers to the Arctic? No more Hawaii for my Colleagues!

As the Canadian Winter approaches and our country goes into collective hibernation, we start to remind the world how cold it gets here, and that the tourist season is in July.  Still, we Canadians are proud of our hardiness and we will welcome you with open arms if you decide to visit in January.

Still, if you look at a population map of Canada, we mostly live in the southern 10% of our country’s latitudes.  There are thousands of square kilometres of open wilderness to explore.  We want to be warm, but we also love our home country.  Many Canadians travel south for part of the Winter to get some sunshine and shake off the seasonal affective disorder, aka SAD (A perfect name for the disorder if you ask me).  If you are really lucky, you are able travel to warmer climates for work!

We live in the warmer parts.

If you speak to a professional observational astronomer, chances are they have been to one of the following lovely locations for work: Hawaii, Arizona, or Chile.  Turns out that large telescopes need to be placed in warm, dry climates, usually on top of gorgeous mountain chains.  Hard work I know.

This had me thinking about good conditions for Astronomy.  Why not the Canadian Arctic? Sure it’s cold, but it’s dry and skies can be clear for long periods.  Then I saw a story about a scientist named Eric Steinbring who was proposing just that!

Polar Environment Atmospheric Research Laboratory (PEARL) in Canada. Credit: left, Steinbring et al., right, Dan Weaver

Steinbring, who led a team of National Research Council Canada scientists, said that a high Arctic site can “offer excellent image quality that is maintained during many clear, calm, dark periods that can last 100 hours or more.”

 

The team was commenting on recent surveys at the Polar Environment Atmospheric Research Laboratory (PEARL).  They concluded that the site on Ellesmere Island has dark, clear skies approximately 68% of the time, and commented that it “can allow reliable, uninterrupted temporal coverage during successive dark periods, in roughly 100 hour blocks with clear skies and good seeing.”

There are challenges however.  Strong winds can bring in intense storms that only last for short periods, but can still wreak havoc on equipment.  Steinbring’s team has been working on overcoming these challenges, allowing for the potential study of phenomena such as Gravitational Lensing, as well as the construction of multiple telescopes at PEARL.  Future Astronomers could spend a week up North probing the depths of the universe in the frigid cold.

In all fairness, observational astronomers are up all night observing and often sleep through the beautiful warm days, so it’s not really a vacation.  If anything it may be torture to travel to a warm location and not spend a single day in the outdoor warmth.  Not to mention the tops of mountains aren’t all that warm.  The temperature can dip below freezing on Mauna Kea in Hawaii, while the beaches are sitting at 30 degrees Celsius.  Still, the great thing about being an astronomer is that you absolutely love the night sky, and the best night skies in the world are at your doorstep when you visit these locations.  Even visiting the cold reaches of the Arctic is an adventure, and I would say most astronomers have a sense of adventure, choosing to dedicate their lives to exploring the unknown.

Keep doing what you love, wherever it takes you.  Maybe that love will keep you warm on those cold Arctic nights.

 

Motivation Monday: The Quarter Life Crisis

There’s this new thing I heard of recently that people my age and nearby (20-32 roughly) are experiencing.  It’s being called a quarter life crisis.  It’s a time in a person’s life where they are making that change from young adult to ‘real’ adult, and although the trigger is different for everyone, the symptoms are similar.  They feel lost, hopeless, chained to a career that may never pan out.  They’re worried about money constantly, and question every.single.decision…. many times.

Sound familiar?

Let’s go back to the beginning to understand why we feel this way.  When we were young the world moved so slowly.  Days would last (relatively) a long time and we would play all day during the summer! We were fed, clothed, and given toys, without really having to do anything.  We believed in magic (some people still do), Santa Claus, the Tooth Fairy, and all kinds of other mystically awesome things.  We said that when we grew up we would be robots and super heroes and play sports all day.  Even school was easy, we would get to play most of the day, and then come home and play some more, then eat, then play some more, before going to sleep and doing it again the next day.  We were invincible, no aches or pains, bumps and scrapes healed quickly, and we could eat all the sugar we could get our hands on.

Then we got a bit older, school became a bit more difficult, but we still were able to coast by, pick up a few cool skills, play some sports, make some of our best friends ever, get into a good College, and go live away from home! Finally we would become an ‘adult’ and live away from our parents. Alcohol tasted good and we downed it like we were a six year old pounding back a pixie stick.  We ate junk food all day and drank all night and went to a couple classes here and there because our parents are footing the bill, better make the effort right? We became activists for change, we saw the problems in the world and wanted to do everything we could to help.  We had the energy and the time, how could the people running the country not agree with us? We would have sex, try drugs, and expand our minds in every way possible.  And who had time for sleep?  We met the best friends we will ever have, the ones we will surround ourselves with forever.

We did this for four really tough years, but once it was over we were prepared for a career path we chose at 15! Ready to take that $100,000 per year dream job with full benefits and six weeks of vacation! Now we had to go find that perfect partner and buy a big house and be happy forever! Huzzah for adulthood!

How naive we were.

We fell into the real world…the one that our parents talked about.  They tried to tell us how tough it is, but we didn’t care, hell we were already smarter than them.  We quickly found out that everybody else had a degree too, and even retail jobs were scarce. So we went back to school to try and continue the glory days of our College experience, or we got a job at that place we worked at all through College, or we moved back in with our parents to save some money.  Relationships were much tougher, and required effort and time, and putting aside our own needs sometimes.  It became much harder to see our best friends from those days, we used to spend so much time together, and now we can barely find a night when we are both free. We did our best to hold onto our youth, to avoid this scary world that we never thought we would see.

We searched for a good career path, because let’s be honest, the career we dreamed of at 15 didn’t exist, or it was totally different than what we imagined.  We spent 4 years of College growing up and changing, and now that we somewhat understood our adult selves, we wanted something different. All of the real jobs require experience in the field, but we can’t get a job in the first place to earn the experience to get the job to earn the experience…..

So we formulated a plan, and worked hard in the job we didn’t want because hey, it’s work and it’s money.  We eventually moved out of our parents house into an apartment, although with all the crippling student debt we still have and the complete lack of money management skills that we should have been taught in school instead of algebra, we are still barely scraping by.  Now we can’t quit the shitty job we said we would do until something better came along, and it leaves us too tired to work on that passion project we started a few years ago.

Perhaps we met that special someone, that person that makes us feel like a kid again, that we want to spend our life with.  This relationship takes work and isn’t always the perfect coupling we had envisioned earlier in life.  And after being told our whole lives to ‘live in the moment,’ we now have to think about marriage, kids, finding a home, and somehow still saving some money for our retirement 30 years down the road.  How can we find time to go and save the world? We’ve got more important things to deal with.

Even though we are happy most of the time, we are scared.  We have no idea where we are going and if we will ever succeed.  We don’t know if we can afford anything, or if we will ever have anything we dreamed of as kids.   We are trapped in a cycle of working to pay for what little we do have, and we can’t even take a break, because we have to work hard to get the same amazing life all of our friends have. We feel so far behind them.

This is the quarter life crisis.

It’s likely that the story above resonates with everyone a little bit, and some people can really feel depressed thinking about their life and comparing it to what it is ‘supposed’ to be.  But if you feel this way, don’t despair. Here are three points to consider:

1. Know that you aren’t alone – Most people feel this way at some point in their lives.  It’s normal to feel lost once in awhile, and there is no predicting the future.  Knowing that other people share our feelings gives us hope that we can get through it, because everyone else figured it out!

Ever heard the expression ‘The more personal, the more universal?’  It basically means that the more you think you’re the only one who does something, the more likely it is that everyone does it and is hiding it just like you are.  We are more similar than we think.

2. Think of it as more of a transition than a crisis – Really it’s a bit of a knee-jerk response to a life you never expected.  Life is hard, but it takes some getting used to.  You’re now in complete control of your life, which is scary. As you face each challenge head on you will get better at coping, better at finding solutions, and you will build your dream one brick at a time.

3. Trust in yourself – In case you didn’t know, you are the result of a 13.7 Billion year experiment.  You are a clump of atoms that evolved for so long that you learned to walk, talk, and love.  You are a miracle, and someone, somewhere, there exists at least one person who loves you dearly and believes in you completely.  If we only had as much faith in ourselves as our loved ones do, we would be unstoppable.

I remember being a kid, and thinking about being 20 years old.  I thought I would have a job, a house, and get married, but jeez it was so far away I couldn’t imagine how enough time would ever pass.  Life was so long and I would be a kid forever.  This is why we try to hold onto our youth.  We feel nostalgia about the things we loved as kids, because it reminds us of a time when we were innocent and truly free, without a real care or problem.

So how is social media hurting us in all this? 

Whenever we post about our lives, we always want it to be positive.  Social media allows us to tell the world how great things are, but we all feel too shy or embarrassed to say how we really feel, especially when it would make us appear weak or lacking confidence.  The reality is that it wouldn’t be so bad to write it down.  Being occasionally sad or feeling hopeless is innately human, and most people would sympathize with us because they had gone through the exact same thing.

Being on the other side of it, we constantly get to see how happy our friends are, how amazing their lives are, and how cool it is to be in their shoes.  They constantly post about the fun things they are doing, moving forward with their lives, while we sit and think about how our life is shit.  Dramatic eh?

Social media also constantly bombards us with the stories of successful people, with information about how anyone can be a success, and how if you just keep working harder, you can earn some more money and have a better life.  It’s like we’re being told that we need to be better than we already are, which is crap, but that’s a rant for another day.

Ultimately the thing to remember is that we all feel this way sometimes, but by taking action, focussing on the positive, and being truly honest with ourselves, we can work through anything life throws at us.

Maybe dealing with it now will prepare us for that mid life crisis a bit later on.

Storms seen on Uranus!

The seventh planet from the Sun is a boring one.  The best photos we have of Uranus were obtained in January 1986 during the passing of Voyager 2, and they revealed a cold, pale-green, ball of Methane four times the diameter of Earth with very little visible activity.

Boring Old Uranus Credit: NASA/JPL/Voyager

Since then, we’ve learned a lot about Uranus, and it’s far more interesting than we thought.  It has rings, a magnetosphere, and numerous moons.  It has a 98 degree axial tilt, meaning that the poles of the planet cycle through 42 years of sunlight and 42 years of darkness during it’s 84 year journey around the Sun.

Winds on Uranus can reach 900 Km/h, which is exactly what led to a series of new storms observed by Astronomers using the Keck telescope in Hawaii.

Storms on Uranus in Infrared. Image credit: Imke de Pater, University of California, Berkeley / Keck Observatory images.

The above image, taken in infrared on August 6th, 2014, shows large storms in the atmosphere of Uranus.  The images were taken with the 10-meter Keck telescope using adaptive optics, where parts of the telescope’s main mirror quickly shift to correct for the distortion caused by atmospheric turbulence.  This technique has given some of the clearest images of distant objects even taken with ground-based telescopes, rivalling the quality of space telescopes such as Hubble.

“This type of activity would have been expected in 2007, when Uranus’s once-every-42-year equinox occurred and the Sun shined directly on the equator,” Said Heidi Hammel of the Association of Universities for Research in Astronomy.  “But we predicted that such activity would have died down by now. Why we see these incredible storms now is beyond anybody’s guess.”

Uranus is made mostly of Methane and Ammonia in solid ice form, with an atmosphere of Hydrogen, Helium and a bit of Methane to give it the dull green colour.  Since it has no internal heat source, all observed weather should be driven by energy from the Sun.  The stormy results were unexpected, even though the team has been following the weather patterns on Uranus for 10 years.

The storms on Uranus are similar to those observed on the other gas giants, possibly due to differential rotation of the gases in the atmosphere, the Coriolis force.

When we closely observe a distant world, as with a microscope observing smaller structures, we can find a surprising degree of complexity.  Uranus is a simple gas planet, but beneath the think obscuring Methane clouds, we see a world of vortices and storms, magnetism and frigidity, surrounded by complex rings and moons.