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Hello! My name is Ian O'Neill and I've been writing for the Universe Today since December 2007. I am a solar physics doctor, but my space interests are wide-ranging. Since becoming a science writer I have been drawn to the more extreme astrophysics concepts (like black hole dynamics), high energy physics (getting excited about the LHC!) and general space colonization efforts. I am also heavily involved with the Mars Homestead project (run by the Mars Foundation), an international organization to advance our settlement concepts on Mars. I also run my own space physics blog: Astroengine.com, be sure to check it out!
The Soyuz TMA-13 spacecraft (Expedition 18) launches Michael Fincke, Yury V. Lonchakov and Richard Garriott (AP Photo/NASA)
[/caption]…but the station’s toilet has broken down again.
For $30 million, you can get a ride into space for a 10-day trip on board the International Space Station. To Richard Garriott, this is money well-spent. He got to spend months training for the experience and he will use the adventure to carry out experiments, educational programs and to follow in his father’s footsteps. 25-years earlier, Owen Garriott flew on Space Shuttle Columbia, and before that he served on Skylab. Having successfully launched on board the Soyuz launch vehicle on Sunday, Garriott Jr. is keen to make space travel a family affair, and make some history along the way; he is the first second-generation American astronaut ever to be launched into space. It sounds like an exciting few days await the 47 year old computer video game entrepreneur…
But like any positive story, there’s a flip-side. The International Space Station, far from being The Ritz at the best of times, has been inflicted with a rather annoying inconvenience… the main toilet is out of order, requiring all on board to use the Soyuz en-suite. Although it is doubtful Garriott will get a room credit for the inconvenience, I’m sure the view of the Earth rotating below, the excitement of being involved in the biggest space project ever conceived, and the joy of zero-G will more than make up for the bathroom situation…
At 3:01 AM EDT (0701 GMT) Sunday morning, Richard Garriott blasted off from the Central Asian spaceport of Baikonur Cosmodrome in Kazakhstan aboard a Soyuz TMA-13 spacecraft. Expedition 18 is being used to ferry two new crewmembers to the ISS. American astronaut Michael Fincke and Russian cosmonaut Yury Lonchakov will keep Garriott company until tomorrow’s (Tuesday) Soyuz docking with the station where the trio will join the existing ISS crewmembers Commander Sergei Volkov, Flight Engineer Oleg Kononenko and astronaut Gregory E. Chamitoff. Volkov and Kononenko will accompany Garriott when he is scheduled to return back to Earth on October 23rd.
The cosmonaut, astronaut and space tourist wave to onlookers before boarding Soyuz (AP Photo)
“Today, my dream of following in my father’s footsteps to explore new frontiers is being realized,” Garriott said in a statement shortly after launch in reference to his father, 77 year-old retired NASA scientist-astronaut Owen Garriott. “It’s with honour and appreciation that I launch on my greatest adventure yet, and step into a role assumed by only five private individuals before me.”
Watching his son being launched into orbit, Garriott Sr. supports Richard in all his space-faring dreams. “He wants to charge full speed ahead,” said Owen, who flew to the pioneering Sklab space station in 1973 and flew on shuttle Columbia 10 years later.
Richard Garriott has been preparing for this moment for many months, and his excitement is evident in the post on his website before launch. “I feel well prepared for this flight, and have complete faith in my crew mates, our beautiful rocket, and the huge number of people it takes to launch our Soyuz and operate the ISS,” Garriott said, wanting his friends and family to be there with him. “I wish I could share this experience with each of you, in the way I have had the opportunity to experience it.”
U.S. astronaut Owen Garriott looks at the Russian Soyuz TMA-13 that will carry his son into orbit (AP Photo/Dmitry Lovetsky)
Unfortunately, there will be some uncomfortable days aboard the ISS. On Thursday, the main toilet facility broke down in the Russian Zvezda service module, leaving the crew to use the Soyuz bathroom facilities. The main toilet has been the source of much hassle to the crew and flight controllers; back in June Oleg Kononenko had to carry out a lengthy in-orbit plumbing job to get the gas-liquid separator assembly pump replacement up and running. It would appear a similar problem has struck again, only three months later. Perhaps the crew should ask Kononenko to use his skills once more before the cosmonaut has to return back to Earth with Garriott on October 23rd…
For now, plumbing issues to one side, we look forward to seeing Richard Garriott, the sixth space station tourist, carry out his experiments and observations, relaying all his experiences to the rest of the world who cannot afford the $30 million ticket.
“I will return to our earth in a few weeks, with a vast array of photographs, and a lifetime of new stories,” Garriott wrote in his website message. “I look forward to sharing them with you!”
Translucent ice and sand dunes in North Polar Region (NASA/JPL/University of Arizona)
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As the Phoenix Mars lander will agree, it’s cold near Mars’ North Pole. Phoenix is currently seeing the winter frost encroach on its location, bright patches of ice appearing on the rocks surrounding it. Another sure sign of winter at this high latitude is the loss of light; soon day will turn to night, forcing Phoenix to enter a Sun-deprived coma. But as one Mars mission draws to a close, other missions continue their diligent watch over the planet 24/7. One such mission is NASA’s Mars Reconnaissance Orbiter (MRO), using its High Resolution Imaging Science Experiment (or HiRISE for short) to pick out the tiny surface features on the Red Planet from around 320 km (200 miles) above.
As winter sets in on the Martian northern hemisphere, HiRISE continues to capture some stunning images of the translucent icy surface…
Mars dune detail showing the southwesterly dominant wind direction (NASA/JPL/HiRISE)These images were acquired at the end of August by HiRISE, and it is evident there was plenty of ice on the surface of this northern region. The MRO was making a pass over a geographical latitude of 77° when these pictures were taken, capturing the complex cracking of translucent surface ice, contrasting with the dark sand of a vast number of barchan dunes, a feature we often observe on Earth as well as on Mars. Phoenix landed at 68° latitude, a little further south than these HiRISE images, but it can be seen there is a lot more ice for that time of the year only 10° further north of Phoenix’s location (after all, no surface frost was observed by the lander in August).
It is thought that the bright areas of ice in the image above comes from surface frost deposited the previous year, but the polar temperatures remained so cold throughout the Martian summer that the frost didn’t sublimate into the thin atmosphere. So, the surface ice remained throughout the year, gradually undergoing physical changes, creating a polygonal texture when viewed from orbit. The texture was probably down to temperature variations, stressing and cracking the ice.
Looking at the detail of the sand dunes, it becomes apparent that the dunes are still active despite the icy surroundings. The streaks of loose sand appear to indicate a dominant southwesterly wind direction.
Earth atmospheric molecules detected by Venus Express (ESA)
[/caption]If you are an astronomer looking for a habitable exoplanet orbiting a far-off star, what do you look for? We know from personal experience that we need oxygen and water to live on Earth, so this is a good place to start; look for exoplanets with the spectroscopic signature of O2 and H2O. But this isn’t enough. Venus has oxygen and water in its atmosphere too, so if we only used these two indicators as a measure for habitability, we would be sorely disappointed to find a water and oxygen-rich Venus-like world which has little chance of supporting life (as we know it).
In an effort to understand what a “habitable planet” looks like from afar, European Space Agency (ESA) scientists have decided to do a bit of retrospective astronomy. Venus Express, currently in orbit around Venus, is being used to look back at the blue dot we call home to help us understand what a real habitable planet looks like…
Venus Express (sister ship of ESA’s Mars Express) was launched in November 2005 to begin its seven month journey to Venus. As the spacecraft left Earth orbit, it turned around to take a picture of the blue globe with its Visible and Infrared Thermal Imaging Spectrometer (VIRTIS), but the significance of this quick observation wasn’t realised until a year after Venus Express had entered Venusian orbit. Could the robotic craft be used to watch the Earth from afar?
Giuseppe Piccioni, Venus Express VIRTIS Co-Principal Investigator, in Italy, has been heading a sustained campaign of Earth observations using the VIRTIS instrument orbiting a planet 0.3 AU closer to the Sun. Although Venus has often been referred to as “Earth’s sister planet” the difference couldn’t be more stark. With atmospheric pressures some hundred times that of the Earth, with a choking cocktail of poisonous gases and high surface temperatures, Venus is hardly conducive for life. Earth, on the other hand, has a bountiful ecosystem where life has thrived for over three billion years. However, Piccioni is aware that if viewed from a distance, both Earth and Venus contain some of the basic ingredients for life; how can we be sure distant exoplanets are more Earth-like or more Venus-like? After all, planet habitability doesn’t seem to depend on just oxygen and water.
“We see water and molecular oxygen in Earth’s atmosphere, but Venus also shows these signatures. So looking at these molecules is not enough,” says Piccioni. So, in an attempt to seek out other forms of life, the Italian astronomer is looking toward Earth to pick out more subtle signals for the presence of life on alien worlds.
Earth’s oxygen and water as detected by Venus Express. The simulated images of Earth are to show which side of the planet was facing Venus at the time; in actuality Earth would appear as a one-pixel dot (ESA)Venus Express can observe Earth about three times a month, and over the last two years, VIRTIS has captured 40 terrestrial images for analysis. The light captured from these Earth observations cover spectral wavelengths from visible through to near-infrared, but when viewed from Venus, the Earth appears only as a small dot, no bigger than a single pixel in Venus Express’ cameras. Far from being a hindrance, this small dot will help future exoplanet hunters.
Although there are no surface features, this small dot still holds a lot of information. By splitting the light observed into its component wavelengths, the composition of the terrestrial atmosphere can be analysed. Therefore, spectroscopic signals from plant life could be detected for example. “Green plants are bright in the near infrared,” said David Grinspoon, a Venus Express Interdisciplinary Scientist from the Denver Museum of Nature & Science, Colorado, who suggested the programme of sustained Earth observation. “We want to know what can we discern about the Earth’s habitability based on such observations. Whatever we learn about Earth, we can then apply to the study of other worlds,” he added.
Exoplanet hunters are finding more and more alien worlds orbiting stars many light years away, it is only a matter of time before we have the technological ability to image the one-pixel spot of an Earth-like world. By understanding how our habitable planet looks from Venus, we can begin to understand whether these exoplanets are indeed “Earth-like” in every sense of the word…
Matt Gasch of NASA Ames and Betsy Pugel of NASA Goddard examine the remains of a 1966 Apollo test vehicle heat shield (Smithsonian Museum/Eric Long)
[/caption]NASA scientists currently working on the Orion Crew Exploration Vehicle had the rare opportunity to unpack a little piece of history. A visit to Smithsonian Institution’s National Air and Space Museum led them to uncover crates containing the heat shields used during the development of the Apollo Program, some 35 years ago. The shielding has not seen light of day since 1966 when it was dropped from low Earth orbit and protected a test vehicle from fiery re-entry. The NASA scientists hope to learn more about the thermal response of the old heat shield to improve the shielding of the Orion return vessel a whole generation after the pioneering lunar missions…
On July 31st and August 1st, the NASA crew descended on Smithsonian Institution’s National Air and Space Museum Garber Facility to do a bit of space-age archaeology. The facility makes it their job to collect, preserve and restore anything space and aircraft related, ensuring the Apollo heatshieilds were in perfect condition (or as “perfect” as they can be after undergoing re-entry over three decades ago) for the Orion development teams from NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and NASA Ames Research Center, Moffett Field, California. What they unpacked was a space geek’s dream.
“We started working together at the end of June to track down any Apollo-era heat shields that they had in storage,” said Elizabeth Pugel from the Detector Systems Branch at Goddard. “We located one and opened it. It was like a nerd Christmas for us!”
Scientists examine the 1966 Apollo test vehicle heat shield (Smithsonian Museum/Eric Long)
The NASA team managed to eventually track down heat shield material from a test re-entry from low Earth orbit on August 26th, 1966. This material will prove useful in the continuing development of the Constellation Program’s Orion Crew Exploration Vehicle so more information can be gained about the material’s reaction to extreme heat as it was dropped through the atmosphere.
“We are examining the design of the carrier structure (the metal structure that connects the heat shield to the vessel that contains the astronauts) and the heat shield material’s thermal response,” Pugel added.
“The Smithsonian has been generous in their providing large pieces of the heat shield that we will be doing destructive and non-destructive testing on during the months before Orion’s Preliminary Design Review,” said Matthew Gasch from NASA Ames. “This information will further our confidence in our design and materials development.”
It might seem strange that NASA scientists are researching re-entry technology from the Apollo era, after all the Orion cone-like design borrows its shape from the Apollo Program’s Saturn V Command Module (amongst others), but that is where the 20th century similarity ends. Orion will be packed with the most advanced 21st century computing, electronics, life support, propulsion and heat protection systems.
Orion aside, I would have loved to have been there when the NASA Orion scientists cracked open the wooden Apollo crates (using crowbars, naturally), to find them filled with the dusty artefacts from the beginning of the space age (but then again, I might be watching way too much Indiana Jones movies…).
A previous Progress approach to the Space Station over Earth (NASA)
[/caption]This may come as a surprise, but then again, it might not. Despite the recently signed US Congressional waiver of the Iran-North Korea-Syria Nonproliferation Act, allowing NASA to use the Russian Progress vehicle to send US supplies to the International Space Station (ISS) after Shuttle decommissioning in 2010, NASA has said that they will seek out US-based commercial launch options instead. NASA has lobbied the US government for months to allow them to continue using Russia’s launch capabilities, but since the recent launch success of US-based Space Exploration Technologies (SpaceX) Falcon 1 rocket on September 28th, hopes are high that this option will stop NASA’s dependence on Russia…
The Iran-North Korea-Syria Nonproliferation Act (INKSNA) basically prevents entities in the US from doing business with Russia if Russia is doing business with Iran, North Korea or Syria to further their development of nuclear technology. However, one such US “entity” is NASA and the space agency has been working with Russia’s space program since the Act was signed in 2000 (even though it is known that Russia has been providing technology to Iran to pursue their nuclear ambitions). NASA has been able to do this by having the INKSNA waived by Congress. The current waiver was valid until 2011, so NASA has been pursuing a waiver extension to prevent the US from being barred from access to space after Shuttle retirement in 2011.
Although they are now legally entitled, NASA has now said that it will not require the use of the Russian Progress supply ships to deliver US supplies to the station, even after the successful signing of a waiver extension (until 2016) last week.
“NASA’s policy has not changed,” NASA spokesman David Steitz said last Thursday (October 2nd). “NASA will rely on U.S. commercial cargo services to resupply ISS following retirement of the shuttle, and does not intend to purchase Progress cargo services after 2011.”
This decision comes after the successful launch of the first ever commercial space vehicle on September 28th. SpaceX will have been relieved the fourth flight of the Falcon 1 rocket system operated flawlessly, proving to NASA that a dummy payload can be lifted into orbit by a private company. The previous flight (Flight 3, on August 2nd) suffered a stage separation anomaly, which caused the loss of two NASA satellite systems, NanoSail-D (a prototype solar sail) and PRESat (mini-laboratory to carry out tests on yeast cells).
Although NASA has announced there are no plans to use the Russian Progress spaceship beyond 2011, it is still an option if required. Elon Musk, CEO of SpaceX is not concerned about NASA opting to use Progress over a US company’s launch system. “I think it’s probably a good thing NASA’s hands aren’t tied there. It’s possible we may lose a few flights to the Russians but we are not going to lose more than that. There is no way Congress would tolerate sending millions of dollars to the Russians rather than to a U.S. company and keeping that money domestic,” he said. Regardless of which political party is voted into government in November, Musk pointed out that, “…neither [U.S. political party] likes sending money overseas if there’s a U.S. supplier.”
According to today’s news release, the waiver still allows the use of the Russian Soyuz system (for manned missions to the ISS), which is fortunate as there is no other US manned option available…
Direct hit - could a huge impact on Mars have snuffed the chances of life? (Karen Carr)
[/caption]We keep sending missions to Mars with the key objective to search for past or present life. But what if a huge impact early in the Red Planet’s history hindered any future possibility for life to thrive? Recent studies into the Martian “crustal dichotomy” indicate the planet was struck by a very large object, possibly a massive asteroid. Now researchers believe that this same impact may have scrubbed any chance for life on Mars, effectively making the planet sterile. This asteroid may have penetrated the Martian crust so deep that it damaged the internal structure irreparably, preventing a strong magnetic field from enveloping the planet. The lack of a Mars magnetosphere thereby ended any chance for a nurturing atmosphere…
Mars looks odd. Early astronomers noticed it, and today’s observatories see it every time they look at the red globe. Mars has two faces. One face (the northern hemisphere) is composed of barren plains and smooth sand dunes; the other face (the southern hemisphere) is a chaotic, jagged terrain of mountains and valleys. It would appear the crustal dichotomy formed after a massive impact early in the development of Mars, leaving the planet geologically scarred for eternity. But say if this impact went beyond pure aesthetics? What if this planet-wide impact zone represents something a lot deeper?
To understand what might have happened to Mars, we have to first look at the Earth. Our planet has a powerful magnetic field that is generated near the core. Molten iron convects, dragging free electrons with it, setting up a huge dynamo outputting the strong dipolar magnetic field. As the magnetic field threads through the planet, it projects from the surface and reaches thousands of miles into space, forming a vast bubble. This bubble is known as the magnetosphere, protecting us from the damaging solar wind and prevents our atmosphere from eroding into space. Life thrives on this blue planet because Earth has a powerful magnetic solar wind defence.
Although Mars is smaller than Earth, scientists have often been at a loss to explain why there is no Martian magnetosphere. But according to the growing armada of orbiting satellites, measurements suggest that Mars did have a global magnetic field in the past. It has been the general consensus for some time that Mars’ magnetic field disappeared when the smaller planet’s interior cooled quickly and lost its ability to keep its inner iron in a convective state. With no convection comes a loss of the dynamo effect and therefore the magnetic field (and any magnetosphere) is lost. This is often cited as the reason why Mars does not have a thick atmosphere; any atmospheric gases have been eroded into space by the solar wind.
However, there may be a better explanation as to why Mars lost its magnetism. “The evidence suggests that a giant impact early in the planet’s history could have disrupted the molten core, changing the circulation and affecting the magnetic field,” said Sabine Stanley, assistant professor of physics at the University of Toronto, one of the scientists involved in this research. “We know Mars had a magnetic field which disappeared about 4 billion years ago and that this happened around the same time that the crustal dichotomy appeared, which is a possible link to an asteroid impact.”
During Mars’ evolution before 4 billion years ago, things may have looked a lot more promising. With a strong magnetic field, Mars had a thick atmosphere, protected from the ravages of the solar wind within its own magnetosphere. But, in an instant, a huge asteroid impact could have changed the course of Martian history forever.
“Mars once had a much thicker atmosphere along with standing water and a magnetic field, so it would have been a very different place to the dry barren planet we see today.” – Monica Grady, professor of planetary and space sciences at the Open University.
Losing its magnetic field after the deep asteroid impact catastrophically damaged the internal workings of the planet, Mars quickly shed its atmosphere, thereby blocking its ability to sustain life in the 4 billion years since. What a sad story…
Foton M3 after landing in Kazakhstan after the experiment. Samples, including Orkney sample, are screwed onto
[/caption]In an effort to understand how organic chemicals might survive after a period in the vacuum of space and then violent re-entry through the atmosphere, scientists have uncovered some interesting results. Last year, the ESA/Russian Foton-M3 mission was launched to test the effects of microgravity on various biological samples. However, a sample of Orkney rock had a harder journey than most. Attached to the outside of the craft, this sample underwent extreme heating during the descent toward the plains of Kazakhstan. Although most of the sample was vaporized, scientists have unveiled results that the sample still contains very obvious signs that it once harboured life. These exciting results set new limits on how organic chemicals may survive unaltered for long periods in space before plunging through a planetary atmosphere, plus it raises some interesting questions into how future searches for extraterrestrial life may be performed…
The principal mission objective for many planetary missions is the search for extraterrestrial life. Although many of our robotic explorers cannot detect life directly, they are able to carry out a host of mini lab experiments on samples taken from the planets surface. NASA’s Phoenix Mars Mission for example has been tirelessly slaving over its hot oven (a.k.a. the Thermal and Evolved-Gas Analyzer, or TEGA for short), dropping samples of Mars soil into its single-use kilns for the last few months. This effort is to vent any prebiotic chemicals into a gas form so instrumentation can then “sniff” the vapour. Should organic chemicals be found, there will be an improved chance that life may have evolved on the Red Planet’s surface.
But say if there is an easier (and cheaper) way to look for ET? Rather than sending hundreds of millions of dollars-worth of hardware to Mars to look for organic chemicals, why can’t we analyse all the rocky samples littered across the globe that originated from space? After all, we now know that some meteorites originate from Mars itself, surely we can perform a far more detailed analysis on these samples instead of depending on a robot millions of miles away?
The big stumbling block comes if we consider the extreme temperatures meteorites are put under during re-entry into the terrestrial atmosphere. Generally one would expect any evidence for past life (whether that be organic chemicals or fossilized remains) to be blow-torched out of existence by reentry temperatures up to 3,000°F (1,650°C). So, researchers from the University of Aberdeen, Scotland, decided to test a chunk of rock from a Scottish island by subjecting it to several days in space and then seeing if any evidence of life in the rock sample remained intact after the descent.
the Kazakhstan landing site of Foton-M3 in September 2007 (R. Demets/F. Brandstatter)
“The specially prepared piece of Orkney rock took part in the unmanned Foton M3 mission which aimed to examine the rock’s behaviour when it was exposed to the extreme temperatures involved in it’s re-entry through the Earth’s atmosphere,” Professor John Parnell, lead scientist in the study, said.
The reason why Orkney rock was used is because of the material’s robustness when exposed to extreme heat. After all, meteorites need to be made of tough stuff to make it to the ground. “Three quarters of the rock, which was about the size of a small pork pie, was burnt off in the experiment. However, the quarter which returned to Earth has shown us that if intelligent life were to have come into contact with the rock, it would have provided them with evidence that life exists on another planet.”
Now this is where the implications behind these results become abundantly clear. If this piece of rock was sent out into space, only for it to eventually encounter an alien world with intelligent life on its surface, it is conceivable that the rock would survive reentry, preserving the organic chemicals for further study by extraterrestrials. Of course, the reverse is true. If life existed (or exists) on Mars, perhaps we should take a closer look at those Martian meteorite samples…
In the case of the Orkney sample, it contains the remains of 400 million year-old algae, providing a rich chemical signature that Parnell and his team could detect. “We would be extremely excited if we found similar remains in a meteorite arriving from another world,” he added.
Although this experiment only scratches the surface of how organic chemicals may last, unaltered, in space (after all, should a meteoroid sample float in space for millions of years, could organic chemicals be altered by cosmic rays?), it does help us understand that for lower energy reentries, organic chemicals can indeed survive the burn…
Could the magnetic field of the Earth really reverse in 2012? I wouldn't bet on it...
[/caption]Apparently, on December 21st 2012, our planet will experience a powerful event. This time we’re not talking about Planet X, Nibiru or a “killer” solar flare, this event will originate deep within the core of our planet, forcing a catastrophic change in our protective magnetic field. Not only will we notice a rapid reduction in magnetic field strength, we’ll also see the magnetic poles rapidly reverse polarity (i.e. the north magnetic pole will be located over the South Pole and vice versa). So what does this mean to us? If we are to believe the doomsayers, we’ll be exposed to the vast quantities of radiation blasting from the Sun; with a reversing magnetic field comes a weakening in the Earth’s ability to deflect cosmic rays. Our armada of communication and military satellites will drop from orbit, adding to the chaos on the ground. There will be social unrest, warfare, famine and economic collapse. Without GPS, our airliners will also plough into the ground…
Using the Mayan Prophecy as an excuse to create new and explosive ways in which our planet may be destroyed, 20 12 2012 doomsayers use the geomagnetic shift theory as if it is set in stone. Simply because scientists have said that it might happen within the next millennium appears to be proof enough that it will happen in four years time. Alas, although this theory has some scientific backing, there is no way that anyone can predict when geomagnetic reversal might happen to the nearest day or to the nearest million years…
Firstly, let’s differentiate between geomagnetic reversal and polar shift. Geomagnetic reversal is the change in the magnetic field of the Earth, where the magnetic north pole shifts to the South Polar Region and the south magnetic pole shifts to the North Polar Region. Once this process is complete, our compasses would point toward Antarctica, rather than northern Canada. Polar shift is considered to be a less likely event that occurs a few times in the evolutionary timescale of the Solar System. There are a couple of examples of planets that have suffered a catastrophic polar shift, including Venus (which rotates in an opposite direction to all the other planets, therefore it was flipped upside down by some huge event, such as a planetary collision) and Uranus (which rotates on its side, having been knocked off-axis by an impact, or some gravitational effect caused by Jupiter and Saturn). Many authors (including the doomsayers themselves) often cite both geomagnetic reversal and polar shift as being one of the same thing. This isn’t the case.
So, on with geomagnetic reversal…
How often does it happen? The Earths interior (University of Chicago)The reasons behind the reversal of the magnetic poles is poorly understood, but it is all down to the internal dynamics of Planet Earth. As our planet spins, the molten iron in the core flows freely, forcing free electrons to flow with it. This convective motion of charged particles sets up a magnetic field which bases its poles in the North and South Polar Regions (a dipole). This is known as the dynamo effect. The resulting magnetic field approximates a bar magnet, allowing the field to envelop our planet.
This magnetic field passes through the core to the crust and pushes into space as the Earth’s magnetosphere, a protective bubble constantly being buffeted by the solar wind. As the solar wind particles are usually charged, the Earth’s powerful magnetosphere deflects the particles, only allowing them into the polar cusp regions where the polar magnetic fieldlines become “open.” The regions at which these energetic particles are allowed to enter glow as aurorae.
Usually this situation can last for aeons (a stable magnetic field threaded through the North and South Polar Regions), but occasionally, the magnetic field is known to reverse and alter in strength. Why is this?
A chart showing Earths polarity reversals over the last 160 million years. Black = normal polarity, White = reversed polarity. From Lowrie (1997)
Again, we simply do not know. We do know that this magnetic pole flip-flop has occurred many times in the last few million years, the last occurred 780,000 years ago according to ferromagnetic sediment. A few scaremongering articles have said geomagnetic reversal occurs with “clockwork regularity” – this is simply not true. As can be seen from the diagram (left), magnetic reversal has occurred fairly chaotically in the last 160 million years. Long-term data suggests that the longest stable period between magnetic “flips” is nearly 40 million years (during the Cretaceous period over 65 million years BC) and the shortest is a few hundred years.
Some 2012 theories suggest that the Earth’s geomagnetic reversal is connected to the natural 11-year solar cycle. Again, there is absolutely no scientific evidence to support this claim. No data has ever been produced suggesting a Sun-Earth magnetic polarity change connection.
So, already this doomsday theory falters in that geomagnetic reversal does not occur with “clockwork regularity,” and it has no connection with solar dynamics. We are not due a magnetic flip as we cannot predict when the next one is going to occur, magnetic reversals occur at seemingly random points in history.
What causes geomagnetic reversal? The model Earth, can a magnetic field be modelled in the lab? (Flora Lichtman, NPR)Research is afoot to try to understand the internal dynamics of our planet. As the Earth spins, the molten iron inside churns and flows in a fairly stable manner for millennia. For some reason during geomagnetic reversal, some instability causes an interruption to the steady generation of a global magnetic field, causing it to flip-flop between the poles.
In a previous Universe Today article, we discussed the efforts of geophysicist Dan Lathrop’s attempts to create his own “model Earth,” setting a 26 tonne ball (containing a molten iron analogue, sodium) spinning to see if the internal motion of the fluid could set up a magnetic field. This huge laboratory experiment is testament to the efforts being put into understanding how our Earth even generates a magnetic field, let alone why it randomly reverses.
A minority view (which, again is used by doomsayers to link geomagnetic reversal with Planet X) is that there may be some external influence that causes the reversal. You will often see associated with the Planet X/Nibiru claims that should this mystery object encounter the inner Solar System during its highly elliptical orbit, the magnetic field disturbance could upset the internal dynamics of the Earth (and the Sun, possibly generating that “killer” solar flare I discussed back in June). This theory is a poor attempt to link several doomsday scenarios with a common harbinger of doom (i.e. Planet X). There is no reason to think the strong magnetic field of the Earth can be influenced by any external force, let alone a non-existent planet (or was that a brown dwarf?).
The magnetic field strength waxes and wanes… Variations in geomagnetic field in western US since last reversal. The vertical dashed line is the critical value of intensity below which Guyodo and Valet (1999) consider several directional excursions to have occurred.New research into the Earth’s magnetic field was published recently in the September 26th issue of Science, suggesting that the Earth’s magnetic field isn’t as simple as we once believed. In addition to the North-South dipole, there is a weaker magnetic field spread around the planet, probably generated in the outer core of the Earth.
The Earth’s magnetic field is measured to vary in field strength and it is a well known fact that the magnetic field strength is currently experiencing a downward trend. The new research paper, co-authored by geochronologist Brad Singer of the University of Wisconsin, suggests that the weaker magnetic field is critical to geomagnetic reversal. Should the stronger dipole (north-south) field reduce below the magnetic field strength of this usually weaker, distributed field, a geomagnetic reversal is possible.
“The field is not always stable, the convection and the nature of the flow changes, and it can cause the dipole that’s generated to wax and wane in intensity and strength,” Singer said. “When it becomes very weak, it’s less capable of reaching to the surface of the Earth, and what you start to see emerge is this non-axial dipole, the weaker part of the field that’s left over.” Singer’s research group analysed samples of ancient lava from volcanoes in Tahiti and Germany between 500,000 and 700,000 years ago. By looking at an iron-rich mineral called magnetite in the lava, the researchers were able to deduce the direction of the magnetic field.
The spin of the electrons in the mineral is governed by the dominant magnetic field. During times of strong dipolar field, these electrons pointed toward the magnetic North Pole. During times of weak dipolar field, the electrons pointed to wherever the dominant field was, in this case the distributed magnetic field. They think that when the weakened dipolar field drops below a certain threshold, the distributed field pulls the dipolar field off-axis, causing a geomagnetic shift.
“The magnetic field is one of the most fundamental features of the Earth,” Singer said. “But it’s still one of the biggest enigmas in science. Why [the flip] happens is something people have been chasing for more than a hundred years.”
Our meandering magnetic pole The movement of Earth's north magnetic pole across the Canadian arctic, 1831--2001 (Geological Survey of Canada)Although there appears to be a current downward trend in magnetic field strength, the current magnetic field is still considered to be “above average” when compared with the variations measured in recent history. According to researchers at Scripps Institution of Oceanography, San Diego, if the magnetic field continued to decrease at the current trend, the dipolar field would effectively be zero in 500 years time. However, it is more likely that the field strength will simply rebound and increase in strength as it has done over the last several thousand years, continuing with its natural fluctuations.
The positions of the magnetic poles are also known to be wondering over Arctic and Antarctic locations. Take the magnetic north pole for example (pictured left); it has accelerated north over the Canadian plains from 10 km per year in the 20th Century to 40 km per year more recently. It is thought that if the point of magnetic north continues this trend, it will exit North America and enter Siberia in a few decades time. This is not a new phenomenon however. Ever since James Ross’ discovery of the location of the north magnetic pole for the first time in 1831, it’s location has meandered hundreds of miles (even though today’s measurements show some acceleration).
So, no doomsday then?
Geomagnetic reversal is an engrossing area of geophysical research that will continue to occupy physicists and geologists for many years to come. Although the dynamics behind this event are not fully understood, there is absolutely no scientific evidence supporting the claim that there could be a geomagnetic reversal around the time of December 21st, 2012.
Besides, the effects of such a reversal have been totally over-hyped. Should we experience geomagnetic reversal in our lifetimes (which we probably won’t), it is unlikely that we’ll be cooked alive by the Solar Wind, or be wiped out by cosmic rays. It is unlikely that we’ll suffer any mass extinction event (after all, early man, homo erectus, lived through the last geomagnetic shift, apparently with ease). We’ll most likely experience aurorae at all latitudes whilst the dipolar magnetic field settles down to its new, reversed state, and there might be a small increase in energetic particles from space (remember, just because the magnetosphere is weakened, doesn’t mean we wont have magnetic protection), but we’ll still be (largely) protected by our thick atmosphere.
Satellites may malfunction and migrating birds may become confused, but to predict world collapse is a hard pill to swallow.
In conclusion:
Geomagnetic reversal is chaotic in nature. There is no way we can predict it.
Simply because the magnetic field of the Earth is weakening does not mean it is near collapse. Geomagnetic field strength is “above average” if we compare today’s measurements with the last few million years.
The magnetic poles are not set in geographical locations, they move (at varying speeds) and have done ever since measurements began.
There is no evidence to suggest external forcing of internal geomagnetic dynamics of the Earth. Therefore there is no evidence of the solar cycle-geomagnetic shift connection. Don’t get me started on Planet X.
So, do you think there will be a geomagnetic reversal event in 2012? I thought not.
Once again, we find another 2012 doomsday scenario to be flawed in so many ways. There is no doubt that geomagnetic reversal will happen in the future for Earth, but we’re talking about time scales anything from an optimistic (and unlikely) 500 years to millions of years, certainly not in the coming four years…
Sources: NASA, US News, SciVee, How To Survive 2012, AGU
All the particles (excluding their anti-particles) gather for a photo opportunity (Particle Zoo)
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This is a must for any particle physics enthusiast: collect your own particles in the form of a soft, cuddly plushie. From the theoretical Higgs boson to the well known electron, all the quantum particles from the Standard Model can be browsed and chosen for your personal collection. The Particle Zoo is the brain child of Los Angeles-based Julie Peasley, who is making it her duty to give our beloved particles a face and personality. For example: due to his popularity, the Higgs particle is a “bit of a snob” and therefore has a huge smile on his face (after all, wouldn’t you be really smug if everyone wanted to interview you?); the muon (or heavy electron) “lives fast and dies young“; or, hilariously, the unobserved graviton “has big legs for jumping branes.” All the particles have a story and a loving personality. Who would have thought quantum physics could be so much fun?
So that's what the LHC is looking for! Meet the Higgs particle (The Particle Zoo)When I first stumbled across The Particle Zoo website I was in awe of the effort Particle Zookeeper Julie Peasley had put into her creations. On reading the descriptions of each particle’s personalities I realised these fun characters were more than just for entertainment purposes; they were a way to communicate the complex physics behind the quantum world to an audience who didn’t necessarily have a specialist background, but would appeal greatly to physicists too.
“If the particle toys can generate an interest in physics and the subatomic world, I’m grateful. At the very least now all my friends and family know what a boson is,” Julie responded when I asked about the educational uses for these cute creations. Teachers, professors and science educators have ordered whole sets of the particles for use in their physics lessons, proving that The Particle Zoo is not simply ‘just for fun.’
Identifying a face and personality for all the quarks, leptons, bosons, nucleons and theoreticals is not a task to be taken lightly, however. Every characteristic of the professionally-made particles must be likened to their real-world counterpart, thereby ensuring scientific accuracy. If the particle is heavy, it will be filled with something weighty, like gravel (check out the vital statistics for the Higgs boson for example); if it is massless, it is filled with light weight poly fill (such as the photon).
“The particles seem to be catching on more and more. I had a “special” on the Higgs particle all day on September 10 to celebrate the startup. I sold a record amount of particles in a short time. So I am now only $999,999,689 away from buying my own LHC.” – Particle Zookeeper Julie Peasley.
Julie spends some quality time with her Standard Model particles (The Particle Zoo)But there is a lot more to it than matching the physical characteristics of the quanta with the plushie. Julie realised after a compelling lecture by Dr. Lawrence Krauss at UCLA that subatomic particles could have different “personalities” that could be embodied through her talents as an artist (she holds a Fine Arts degree from the University of Colorado) and her lifelong interest in cosmology, the quantum mechanics and theoretical physics. After Krauss’ lecture on The Beginning and End of Time, she hit the textbooks, finding Lisa Randall’s Warped Passages to be a key element to her enthusiasm to giving the particles a face. Each particle has a face that reflects its “personality” – take the neutron with a neutral expression, or the hard-to-detect neutrinos who are all dressed up like little ninjas; every one is designed with a subtle touch.
Select your favourite particle (and don't forget your anti-particles!) (Particle Zoo)In reference to the light-hearted organization, the People for the Ethical Treatment of Hadrons, or simply “PETH” (a group set up to protect the rights of hadrons in particle colliders. After all, how do we know protons don’t feel pain?), Julie said, “I love the idea of hadron’s rights, that is hilarious. Actually, I’m quite jealous of the little hadrons who get to collide at the LHC. They get to go 99.999999% the speed of light. How cool is that?”
Although the LHC has suffered a technical hitch, and the first particle collisions aren’t expected to commence until spring 2009, The Particle Zoo will allow you to explore the quantum world for the time being. I for one have ordered my very own Higgs boson in preparation for my celebrations for when the first particles are collided by the LHC.
“I had a collection of the Giant Microbes toys and thought if people enjoyed those, maybe they would enjoy taking it a step further (well, to be honest, many orders of magnitude further). I honestly had no idea if anyone would be interested but I’m happy to say I’ve gotten over and beyond the positive response I could have imagined.” – Particle Zookeeper Julie Peasley.
So for now, any Higgs boson discovery will fall to Julie’s skilled hands in her “sweatshop of one” until the real force carrier is either proven or disproven in a few months time…
(Warning: Be sure not to leave any anti-particles mingling with the “normal” particles on the same shelf… the resulting annihilation may leave you swamped with fluffy photons…)
Astronaut Greg Chamitoff contemplates his next move on the ISS (NASA)
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In one of the grandest chess challenges ever attempted, a Canadian space station astronaut will contemplate his moves from orbit whilst students on Earth will make theirs from the ground. Greg Chamitoff, an International Space Station (ISS) flight engineer, has been stationed on the orbital outpost for four months and he is filling his spare time following his favorite intellectual hobby. The chess enthusiast has been playing the board game with space centres around the world, and is so far undefeated. Let’s see if he can beat some of the brightest strategists from kindergarten through to a third grade US Chess Championship Team…
Many of you may be thinking: hasn’t a space station engineer got better things to do with his time rather than playing chess? And you would be right, Chamitoff has a busy schedule to maintain and only has a limited amount of recreational time on his hands. This is why only one move per day will be allowed. This slow game may even get longer should his orbital duties eat into his spare time. However, this is a great chance for the public to experience a rather unique chess match transmitted over an altitude of 210 miles.
“For the past 10 years, the International Space Station has been an important platform to learn about living in space. We’re excited to have the opportunity to engage not only young students, but the public at large in this unique chess match,” said Heather Rarick, lead flight director for the current space station mission at NASA’s Johnson Space Center in Houston. After all, this match will not only boost interest for space exploration in the classroom, it might create many chess enthusiasts (after all, it’s not every day you get to challenge an astronaut to a board game).
US Chess Federation (USCF) Executive Director Bill Hall shares this sentiment. “Chess is a valuable tool to lead students to become interested in math and to develop critical thinking skills, objectives we focus on in our work with schools nationwide,” he said.
The match is focused on school children in kindergarten through to the third grade US Chess Championship Team, including chess club members from Stevenson Elementary School in Bellevue, Washington. The students choose four possible moves in reply to Chamitoff’s and then the public votes on the best move to be transmitted to orbit.
Chamitoff carried his custom-made chess set into orbit when he few on the STS-124 shuttle mission which delivered components for the Japanese Experiment Module, “Kibo”. Each chess piece is attached to the board with Velcro to prevent the pawns and knights from floating around the station’s Harmony module where the match is taking place. In the ISS video on the USCF website (the organization which set up the event), Chamitoff said after ripping his knight from g1, “It’s your move. Good luck. I’m not gonna make it easy for you. And thanks for playing!”
