It seems the sky is falling…

Imagine driving in your car on a lovely Friday morning and seeing a flaming ball of death streaking across the sky and coming, as best you can tell, right at you.

This view from a Russian dashboard camera shows a terrifying view of the fireball as the meteoroid entered the atmosphere and hurtled over the city of Chelyabinsk. Credit: Discovery News

That’s what terrified citizens in the lovely Russian city of Chelyabinsk experienced on the morning of Friday, February 15. The multitude of videos and photos of this meteor are simply horrifying since many of them give the impression that this huge chunk of flaming interplanetary death is about to smash right into the camera. Not only did this fireball make a scary visual impression, but it packed a very literal punch as well. As the meteoroid hurtled through the atmosphere at 40,000 mph, the heat and pressure it felt caused it to break apart with a huge amount of energy, the equivalent of 470 kilotons of TNT (or 30-40 times the power of the atomic bomb dropped on Hiroshima). The deposition of that huge amount of energy into the sky caused a pressure wave that blasted the city. Over 1,000 people were injured by the blast, mostly due to cuts and scrapes from glass as windows shattered. Scientists have now come to the conclusion that the initial object was only 17 meters wide– that’s about the size of a tractor trailer. That’s pretty small cosmically speaking. Imagine the damage that could have been inflicted if something larger had hit the atmosphere. The last time a meteor had significant large-scale impact was in 1908, again in Russia. This impact, known as the “Tunguska event“, is the largest impact ever recorded- 20-30 times larger than the one that happened this month. This meteoroid, which is estimated to have been about 100 meters wide (the size of a football field), blew up in the air and released 10-15 megatons of energy, leveling 830 square miles of trees. Witnesses to the event said that the heat and pressure from the explosion made their skin feel like it was on fire.

The 1908 Tunguska event, the largest impact near or on Earth ever recorded, leveled trees over 830 square miles. Credit: nightsky.org

Luckily the 2013 Russian meteor was much smaller, so windows got knocked out but buildings weren’t leveled. The object was actually so small that astronomers didn’t even see it coming. NASA has a whole division of people who track objects that could potentially come close to Earth, it’s known as the Near-Earth Object Program. Unfortunately, for scientists to be able to see an object it needs to be large enough to reflect an observable amount of light. That didn’t happen here.

The meteor also came as a bit of a shock since scientists were so focused on another Near-Earth Object called 2012 DA14. This 45-meter wide asteroid was scheduled for a flyby of Earth on the same day, February 15. This relatively small piece of space rock flew closer to the Earth than any other celestial body. It was 17,200 miles away at its closest approach, that’s closer than satellites in geosynchronous orbit and much, much closer than the Moon. Although scientists were certain that DA14 wouldn’t impact the Earth, they were very excited to use the close flyby as an opportunity to study the asteroid.

This collage of 72 individual radar-generated images of asteroid 2012 DA14 was created using data from NASA’s 230-foot Deep Space Network antenna at Goldstone, CA. Credit: NASA

Of course it was ironic that after weeks of assuring the public that there was no threat of an impact from DA14 another huge impact happened in Russia the same day. Scientists from NASA’s Meteoroid Environment Office concluded that the Russian meteor and DA14 were totally unrelated, having come from two very distinct trajectories/orbits. This means it was a huge cosmic coincidence that they just happened to occur on the same day…weird.

This plot of the orbits of the Russian meteor and asteroid 2012 DA14 show that the two bodies came from very different parts of the solar system and were unrelated. The Russian meteoroid most likely originated from the Asteroid Belt out past Mars. Credit: NASA/Space.com

The world will not end today…

Okay, this is really getting pretty infuriating. I have friends, family, and strangers messaging me about when the planets will align tomorrow.

So let’s set the record straight…or at least as much as we can by answering a few simple questions regarding this Mayan end-of-the-world who-hah and why the world will NOT end today.

Where did this idea of the world ending even come from?

The ancient Maya civilization (aka the Mayans), that lived in Central America from roughly 1800 BC until the Spanish wiped the last of them out around 1700 AD were great astronomers. They had their own constellations, pre-telescopic knowledge of the Orion Nebula as a fuzzy object in the sky, and some of their sites are oriented to astronomical objects such as the Pleiades star cluster. Like many advanced cultures, the Mayans used a calendar. They didn’t invent the calendar, but they used it, like most Central American civilizations previous to Columbus coming to the New World; however, they did add on to it.

A view of a Mayan calendar wheel. Credit: www.epicpodquest.com

The Maya came up with a very different calendar from what we use. They have what we call “the Long Count”, which is made up of 13 “baktun”. Each “baktun” is comprised of 20 “katun”. Each “katun” is 20 “tun”, each “tun” is 18 “unial”, and each “unial” is 20 “kin”. What the heck does that mean? Well, we can easily make the metaphor that the Mayan “Long Cycle” is like a year in our very own modern day Gregorian calendar. Now, a “kin” to the Maya is equivalent to a modern day, so a Long Cycle is MUCH longer than a Gregorian year- it’s actually roughly 5,125 years. But here I’m using the analogy just to make a point.

Mayan: 1 Long Cycle = 13 baktun = 260 katun = 5,200 tun = 93,600 unial = 1,872,000 kin

Gregorian: 1 millennium = 10 centuries = 100 decades = 1,000 years = 12,000 months = 365,250 days

When you get a Gregorian calendar for your desk or wall, it usually only has a single year in it, for instance, your current calendar probably doesn’t extend into 2013. Of course that doesn’t mean that 2013 doesn’t exist, you just need a new calendar. Well, the same thing happened with the Maya, they stopped generating calendars beyond this current baktun, which would end in our modern Gregorian time at December 21, 2012 at 11:11 GMT. But like I said, this doesn’t mean the world is going to end. It’s this “reset” of the Mayan calendar that has fueled the plethora of end-of-the-world scenarios.

Looking at this another way, imagine if there WAS a cataclysmic end of the world tomorrow and then far in the future an advanced civilization found what was left our world and realized that there were no calendars that existed beyond 2013…what might they conclude? Oh no, the human calendar must have ended after January 31, 2013!? We all know that’s not true, but one could imagine how an ignorant futuristic civilization might be confused.

Based on this “end of the Mayan calendar”, people across the world and across the internet have tried to come up with ways and reasons that the world might end on December 21, 2012. Some of these catastrophes are minutely based on real things, many are not, and almost all of them are ridiculous. On top of that, the movie 2012 didn’t help the commotion.

What is a planetary alignment and is there going to be one?

A planetary alignment, or conjunction, is when planets appear to lineup in the sky from Earth and they occur fairly frequently. There are a lot of hoaxes related to the alignment of the planets and how that will impact Earth. There’s also another idea that the Earth and Sun will align with the center of the Milky Way galaxy and something cataclysmic will happen to destroy the Earth. This isn’t going to happen. Here’s an article by Francis Reddy of NASA Goddard Space Flight Center that explains why an alignment with the galactic center won’t mean the end of days. So no, don’t try to go outside and look for an alignment of planets in the sky, you won’t see anything.

Now, there was some more baloney going around the internet about a planetary alignment over the pyramids at Giza on December 3, 2012. That was also a hoax… aka NOT REAL!

This photo of a supposed December 3 planetary alignment of the pyramids quickly made the rounds all over the internet. Too bad it’s not real. Credit: Bad Astronomy

Is a rogue planet or asteroid going to crash into the Earth?

NO! Of course not! NASA has a whole division of scientists, in the Near-Earth Object Program, who work to identify and track objects that could pose potential danger to Earth. So far, they have no indication that anything will impact the Earth. There are stories of a rogue world called “Nibiru” that is supposedly going to crash into the Earth. This false claim of a rogue planet-destroyer has been warped and somehow now been misconstrued even further to include an actual dwarf planet, called Eris, that lives out in the Kuiper Belt. This planet was originally referred to as “Planet X”- another claimed possible bringer of Earth’s destruction. So recap: Eris is real, was once called Planet X, Nibiru is not real…and NONE OF THEM WILL IMPACT THE EARTH.

Although it might be a nice excuse to get out of work, don’t expect a killer planet to crash into Earth and obliterate it anytime soon. Credit: www.londonlovesbusiness.com

Is the Earth’s magnetic field or a polar shift going to kill us all?

Again, no. Scientists know from rocks on the floor of the oceans that the Earth’s magnetic field, which protects us from the harmful energetic particles that come streaming off the Sun, actually reverses fields. Now, generally the field of Earth does shift every 400,000 years and we’re sort of overdue for one. However, when the magnetic field does reverse (referred to as a polar shift), it won’t be instant- at least we don’t think so- and it probably won’t happen for a couple more millennia.

So there you have it, no the world will not end. Yes, scientists are pretty sure- here’s an official website from NASA addressing these issues and concerns in case you’re not convinced. And finally, yes, people on the internet are crazy. So I guess all that’s left to say then is happy new Long Cycle everyone!

Curiosity did not kill the cat…

So as I’m sure you’ve all heard, NASA’s Curiosity rover successfully landed on the surface of Mars in the early hours of yesterday morning (east coast time). In an earlier post, I relayed the video by NASA of the harrowing entry that Curiosity needed to go through to reach the Martian surface safely and highlighted that the entire elaborate landing procedure was 100% automated since it takes double the time the landing would take to occur for information to be relayed back to Earth. And all the taxings of a mission so complicated, despite all the finesse and delicacy needed to execute such a bold attempt, and despite all the things that could go wrong, the scientists and engineers at NASA succeeded. Honestly, if you watch the 7 Minutes of Terror video, realize that scientists built and programmed a machine that could do that all automatically, millions of miles away from Earth (352 million to be exact) while moving at thousands of miles per hour and have it work flawlessly, and aren’t awed and impressed, then well you should probably check your pulse.

The Mars Science Laboratory’s mission is to investigate the interior of the Gale Crater for signs of microbial life. Top left: A profile of Curiosity’s landing site, Gale Crater. Top Right: A simulation of Curiosity’s proposed mission. Bottom: A map showing the distribution of NASA’s missions to the Martian surface. Credit: BBC News

In addition to being the largest rover we’ve ever sent to another world, twice as long (about 10 feet)  and five times as heavy as NASA’s twin Mars Exploration RoversSpirit and Opportunity, launched in 2003, Curiosity also has new equipment that allows it to gather samples of rocks and soil, process them, and then distribute them to various scientific instruments it carries for analysis; that internal instrument suite includes a gas chromatograph, a mass spectrometer, and a tunable laser spectrometer with combined capabilities to identify a wide range of organic (carbon-containing) compounds and determine the ratios of different isotopes of key elements. There’s clearly a reason why the mission is called the Mars Science Laboratory.

This illustration from NASA shows the size and instrumentation of Curiosity that will help it to investigate the possibility of microbial life on Mars. (A) Six independent wheels allowing the rover to travel over the rocky Martian surface. (B) Equipped with 17 cameras, Curiosity will identify particular targets and then zap them with a  laser to probe their chemistry. (C) If the signal is significant, Curiosity will swing over instruments on its arm for close-up investigation. (D) Samples drilled from rock, or scooped from the soil, can be delivered to two hi-tech analysis labs inside the rover body. (E) The results are sent to Earth through antennas on the rover deck. Return commands tell the rover where it should drive next. Credit: BBC News

According to NASA, Curiosity carries with it “the most advanced payload of scientific gear ever used on Mars’ surface, a payload more than 10 times as massive as those of earlier Mars rovers.” All that gear will be important as Curiosity investigates its main science objective: whether or not there is evidence of microbial life (past or present) in Martian rocks. Although both Spirit and Opportunity listed the search for life as among their scientific goals, neither rover was really equipped to search for microbial life; the twin early generation rovers were more specifically looking for water or the evidence of past water on the Martian surface and then whether that water could sustain life. Curiosity, on the other hand, is specifically equipped to look for microbial life (or evidence of it) in the rocks and soil of the Red Planet. More than just the roving explorer that its forebears were, Curiosity is for all intents and purposes a laboratory on wheels.

This image of Curiosity descending to the Martian surface with its parachute was taken by the High-Resolution Imaging Science Experiment (HiRISE) camera on the Mars Reconnaissance Orbiter. The rover is descending toward the etched plains just north of the sand dunes that fringe Aeolis Mons. Credit: NASA

And it’s not just the instrumentation that Curiosity is equipped with that make NASA rover 2.0 better than previous generations, but the technology it used to get to the Martian surface is leaps and bounds ahead of how Spirit and Opportunity landed. If you watch this NASA movie that highlights the landing process for the Mars Exploration Rovers (which only had six minutes of terror), you’ll notice that most of the landing procedure seems similar to Curiosity’s. Extremely high-speed entry into the Martian atmosphere, heat shield, parachute, rocket thrusters, etc. Until you get to the last step, when Spirit and Opportunity wer basically dropped onto the Martian surface at nearly 60 mph, surrounded by huge air bags, and allowed to bounce three or four times until they settled. Compared to the fine precision placement of the Curiosity rover earlier this week, the previous rovers’ landings were downright barbaric, like trying to hunt a deer by throwing rocks.

This image, one of the first returned by Curiosity, shows the rover’s shadow on the Martian surface and one of the main targets of its mission, Aeolis Mons, on the distant horizon. Credit: CNN

Rather than violently smashing the $2.6 billion rover into the surface and hoping for the best, this descent involved a sky crane and the world’s largest supersonic parachute, which allowed the spacecraft carrying Curiosity to target the specific landing area that NASA scientists had meticulously chosen. That landing area is roughly 12 km (7.5 miles) from the foot of the Martian peak previously known as Mount Sharp. Aeolis Mons, as it’s now known, is the 18,000-foot (5,500-meter) peak at the center of Gale Crater, previously known as Mount Sharp. The stratified composition of the mountain could give scientists a layer-by-layer look at the history of the planet as Curiosity attempts its two-year mission to determine whether Mars ever had an environment capable of supporting life.

Possibly the biggest piece of the NASA Curiosity puzzle has been the enormous PR campaign that NASA has thrown behind the rover. Not only has the rover and it’s 7 Minute of Terror video been all over the internet, TV news, newspapers, and other media outlets, but NASA has even gone out of its way to get high-level stars in the fold. Last week they released this video (above) of William Shatner, most famously known as Capt. James Tiberius Kirk of Star Trek, narrating a preview of Curiosity’s “Grand Entrance” to Mars. There was also another video featuring narration by Wil Wheaton (Wesley Crusher from Star Trek: The Next Generation).

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Ride, Sally Ride…

Sally Kristen Ride (1951-2012) Credit: NASA

Sally Ride, who sadly passed away on Monday from pancreatic cancer, was an American hero. She was a scientist, an explorer, and a pioneer. Not only did she break into a world (or beyond a world really) dominated by men, but she also secretly lived her life as the only confirmed homosexual astronaut. I don’t want to dwell on Ride’s sexual orientation because I feel like that will only put a label on her, but I do feel like it’s an important fact that underlines the impact that Sally Ride had on American society and the magnitude of the obstacles that she must have faced and overcome to achieve what she did. On June 18, 1983, she flew as part of the crew of the Space Shuttle Challenger and became the first American woman in space. She served as an inspiration and role model for millions of young girls to whom science and space seemed an inaccessible “boys club” and spent most of her post-NASA career encouraging young people, specifically girls, to pursue careers in the sciences. As this CNN article reports, Ride’s influence and legacy can be seen in the huge growth in female involvement and success in the sciences. Since Ride, 44 more American women have flown in space (compared to 299 American men)– that’s about 13% of all American spacefarers.

Sally Ride was born on May 26, 1951 in Los Angeles, California. Her father, Dale, was a political science professor at Santa Monica College and her mother, Carol, worked as a volunteer counselor at a women’s correctional facility. Both of her parents were extremely involved in the Presbyterian Church; in fact Sally’s sister, Karen (known as “Bear”), is a Presbyterian minister. After high school, Sally attended Swarthmore College for three semesters, took physics courses at UCLA, and then entered Stanford University as a junior where she double majored in English and Physics. She continued on at Stanford for her graduate education, earning both her master’s degree and Ph.D. in Physics. In 1978, the same year she received her Doctorate, she was selected out of over 8,000 applicants as an astronaut candidate by NASA.

Sally attended flight school as part of her astronaut training. She enjoyed it so much that it became a regular hobby. Credit: Women@NASA

Sally spent the next year in astronaut training, studying parachute jumping, water survival, weightlessness, radio communications, and navigation. In fact, she enjoyed flight training so much that flying became one of her hobbies. During the second and third flights of the space shuttle Columbia, she worked on the ground as a communications officer, relaying messages from mission control to the shuttle crews. She was part of the team that developed the robot arm used by shuttle crews to deploy and retrieve satellites.

Sally Ride, the first American female astronaut, experiencing zero gravity. Credit: Women@NASA

As part of the first-ever five-person Space Shuttle crew for the June 1983 STS-7 mission that made her the first American woman in space and the youngest American in space (at age 32) , Ride participated as the crew deployed satellites for Canada (ANIK C-2) and Indonesia (PALAPA B-1); operated the Canadian-built robot arm to perform the first deployment and retrieval with the Shuttle Pallet Satellite (SPAS-01); conducted the first formation flying of the shuttle with a free-flying satellite (SPAS-01); carried and operated the first U.S./German cooperative materials science payload (OSTA-2); and operated the Continuous Flow Electrophoresis System (CFES) and the Monodisperse Latex Reactor (MLR) experiments. In fact, during the mission Ride became the first woman to operate the shuttle’s robotic arm.

“The thing that I’ll remember most about the flight is that it was fun. In fact, I’m sure it was the most fun I’ll ever have in my life.” – Sally Ride on her first flight in space

Sally would go on to fly again with the 13th Shuttle mission, STS 41-G, which launched from Kennedy Space Center on October 5, 1984. She was assigned to fly again in 1986 on STS 61-M, but all mission training was halted in January after the Challenger explosion. Sally served on the Presidential Commission investigating the tragedy. After the investigation was completed, she was assigned to NASA headquarters as special assistant to the administrator for long-range and strategic planning. There she wrote an influential report entitled “Leadership and America’s Future in Space,” and became the first director of NASA’s Office of Exploration. She also served on the panel investigation the Columbia disaster in 2003; she’s the only person to have served on both investigative panels.

After she retired from NASA in 1987, Sally joined Stanford University Center for International Security and Arms Control. She later became a professor of physics at the University of California, San Diego and she served as president of SPACE.com from 1999 to 2000. Driven by her belief and commitment to encourage young people, especially girls, to study science, she started the Sally Ride Science, a science outreach company, in 2001. She also wrote five science-related children’s books: To Space and Back; Voyager; The Third Planet; The Mystery of Marsand Exploring Our Solar System.

It goes without saying that Sally Ride was among the most influential American women of the 20th century. Her excitement about space and dedication to encouraging young people to study science has benefitted our country immensely. She will be remembered and missed. From all the countless children, boys and girls alike, who want to go to space, thank you Sally for boldly going where no American woman went before.

7 Minutes of Terror…

Hello all! So I made it successfully back to NASA Goddard from Snowmass Village, Colorado. The conference went well, but as with all scientific conferences, it was quite daunting. However to help me recover, this weekend I visited the Smithsonian National Air and Space Museum’s Steven F. Udvar-Hazy Center to see the recently retired Space Shuttle Discovery. As I’ve chronicled in the past, Discovery is by far the most accomplished of the five Shuttles that have flown (of which only three survive)– an impressive resume that puts it in the upper echelon of American vessels right alongside the USS Enterprise (that’s the Navy aircraft carrier, not the fictional starship…). Seeing Discovery in person was extremely impressive. Being able to see the scorch marks from reentry on the underbelly of the nose and then realizing that each individual tile is labeled was very cool. Up close, the Shuttle looked much more like a patchwork of different components than the sleek space-faring plane that I’m used to seeing in photos. The size also caught me off guard. I’m not sure why, but I’ve always assumed that the Space Shuttle must comparable in size to a commercial airplane that most of us are used to, like a Boeing 747, but it’s not, it’s much smaller. I guess in a way it was both bigger and smaller than I expected…if that makes any sense. Below are some pictures of Discovery.

Moving on to other cool space things. Have you ever wondered what it would be like travelling to Mars? Well a new short video from the great folks at NASA Jet Propulsion Laboratory (JPL) out in Pasadena, CA shows how harrowing the journey might actually be. The team working on the new Mars rover, Curiosity (part of the Mars Science Laboratory mission) have released a new video, entitled 7 Minutes of Terror, detailing the rover’s planned 7-minute descent through the Martian atmosphere and onto the surface of the Red Planet. If you’ve ever doubted the ingenuity or ability of NASA scientists and engineers then you should definitely watch this short video (it’s much less than seven minutes long). The sheer magnitude of the problem that they are attempting to tackle is impressive enough (aka landing something the size of a couch on an object millions of miles away), let alone the fact that they are doing it without any communication with the spacecraft (the entire landing process will have been completed in the time it takes communication to reach Earth from Mars) and dealing with insanely sensitive and delicate instrumentation. It’s just a great look at how insanely talented and inspiring the folks at NASA are. Kudos to them.

Curiosity will be the third functioning NASA rover on Mars, joining its Mars Exploration Rover brethren Spirit and Opportunity who landed in 2004 (Opportunity is still functioning), and will specifically be investigating the habitability of Mars. Curiosity was specifically designed to study layers in Martian mountains that hold evidence about wet environments of the planet’s early existence and assess whether Mars ever had an environment able to support microbial life forms. The rover, launched on November 26, 2011, is scheduled to land on the Martian surface, near the base of a mountain inside Gale Crater, close to the Martian equator, early on August 6, 2012 (EDT) to begin its two-year prime mission.

NASA’s next Mars rover, Curiosity, on a test drive. Credit: NASA/JPL

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Magnetic reconnection: a prominent mystery, part 2…

So let’s continue our discussion about the universal mystery of magnetic reconnection. In my previous post “Magnetic reconnection: a prominent mystery, part 1…” we learned about magnetic fields, particularly Earth’s magnetic field. But Earth isn’t the only magnetic field in the universe, in fact most of space is permeated by magnetic fields. The largest and strongest magnetic field near Earth is the Sun’s magnetic field, but every star has a magnetic field and most of the planets do as well. Even the largest moon in the solar system, Jupiter’s moon Ganymede, has a magnetic field– a very intriguing oddity for scientists.

But now back to our real topic of discussion: magnetic reconnection. So what is magnetic reconnection? It’s our leading theory for how a lot of phenomena occur in our universe. We’ve known for decades that large solar flares and blobs of particles called coronal mass ejections (CMEs) come streaming off the Sun. We also have a pretty good understanding that energetic particles, mostly from the solar wind, hit our atmosphere and cause the aurora. We also know that some phenomenon causes odd magnetic field signatures near black holes and certain neutron stars called pulsars.  Scientists believe that magnetic reconnection may be the physical process that ties all of these universal phenomena together.

Magnetic field lines aren’t real, they’re just a representation of the force that a positively-charged particle would experience. Generally, the closer together field lines are, the higher the magnitude- or strength- of the field. A basic principle of physics is that things like to be at what we call the lowest energy state. Like a spring for instance, if a spring had a choice between being stretched out or being relaxed, it will choose to be relaxed, that’s its natural state. Most things in the universe choose to be relaxed. It’s the same for magnetic fields. If magnetic fields have the option of being stretched out and really long or finding a shortcut to relax, they’ll take the shortcut. That’s where magnetic reconnection can occur.

The image below is a simple, not-to-scale depiction of the Sun-Earth system and each body’s magnetic field. Remember that the Earth is tilted with respect to its orbital plane (which consequently causes the seasons on Earth).

Here’s a simple, not-to-scale depiction of the Sun-Earth system.

If it were isolated, the Earth’s magnetic field would look like the Sun’s, but the constant stream of high-speed energetic particles coming off the Sun– the solar wind— actually exerts a pressure on the Earth’s field and causes it to distort. Now take note of the direction of the arrows associated with each body’s magnetic field. In the last post, we noted that Earth’s magnetic north pole is actually in the southern hemisphere, so the field runs from the south pole to the north. The magnetic field that permeates from the Sun, is known as the interplanetary magnetic field (IMF). Now the direction of the Sun’s magnetic field actually changes pretty regularly, but here I’m showing what we call a southward IMF, so it’s opposite to the direction of the Earth’s magnetic field*. Scientists believe that an environment like this, where oppositely directed magnetic field lines come into close contact with each other, is where magnetic reconnection can occur. The diagram below shows an up-close view of what we think occurs. This is what we believe occurs at the boundary between the Earth’s magnetic field and the IMF, a boundary known as the magnetopause. The blue field lines represent Earth’s magnetic field, the field keeping us safe from the highly energetic particles and plasma that are associated with the Sun’s magnetic field (orange). Those orange lines extend all the way back to the poles of the Sun, just as the blue lines “attach” to the Earth’s poles. But as you know, opposites attract, so the field lines make a quick U-turn and “reconnect”. We don’t fully understand the details behind the processes that cause the reconnection, but there are some intense mathematical theories out there.

The basic theory behind magnetic reconnection. First, oppositely directed magnetic field lines come into close contact. Then, in a process that is not fully understood yet, the field lines cross and reconnect. Finally, the two newly-connected field lines relax.

So why do we care, you might ask? Well look at those newly formed field lines, they’re now basically connecting the Earth to the Sun, and inviting the energetic particles and plasma from the Sun into our safe little magnetospheric bubble. It’s those particles streaming into our atmosphere that cause geomagnetic storms and the aurora. And geomagnetic storms can wreak havoc on our power grid, not to mention bombard our satellites with radiation. You might also notice that in the first diagram there’s a region in the back part of Earth’s magnetic field– called the magnetotail— where reconnection might also occur. Here’s a nifty animated movie from NASA that shows three different possible types of reconnection. First, reconnection causes the magnetic field of the Sun to release, loosing a coronal masse ejection (CME). Then the CME hits Earth’s magnetic field and you get reconnection again– that’s the “peeling back” of the field lines that you see there. And then finally you get reconnection a third time in the magnetotail and particles are accelerated into the atmosphere causing the aurora. This isn’t always the way it happens, but it helps you to get a visual idea.

So that’s why the Magnetospheric Multiscale (MMS) mission that I’m working on at Goddard is relavent. Not only do we want to find out more about this process, that might be one of the most prominent phenomena in the universe, but we also want to better understand how and when Earth is exposed to solar radiation. Learning more about the environment necessary for magnetic reconnection may help organizations like NASA and the National Oceanic and Atmospheric Administration (NOAA) better warn us of impending solar weather.

*Note: The north-south orientation of Earth’s magnetic field is known to flip every 250,000 years or so, but I’m only focusing on the current orientation.  It’s a well-documented, but as of yet, very poorly understood phenomenon referred to as magnetic pole reversal. We’re actually way overdue for such a flip, estimates showing that the last one occurred some 800,000 years ago.

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Into the belly of NASA…

Last week I was lucky enough to get to go on a tour of NASA Goddard Space Flight Center with a group of other interns. Let me tell you, this place is amazing. I could try to do this all in words, but I think a lot of these pictures just need to be seen to be believed. So please enjoy the gallery below!

Here are links for more information about the NASA missions mentioned above:

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