Posted on by Irene Antonenko

Fears of Tornado Catastrophes Due to Global Warming Unfounded

Tornadoes in the Midwest US, March 2, 2012 Tornadoes swept the Midwest US on March 2, 2012. In this image, clouds are rendered using thermal infrared (heat) and visible imagery from the Geostationary Operational Environmental Satellite-East (GOES-East). Background land information is from the Moderate Resolution Imaging Spectroradiometer (MODIS). Image credit: NOAA-NASA GOES Project/NASA Earth Observatory.

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The 2012 tornado season got off to a rousing start. Between February 28th and March 3rd, two deadly storm systems developed in the southern United States. The storms spawned numerous tornadoes that together killed at least 52 people. This kind of extreme tornado activity, so early in the year, has fueled fears that global warming will increase the severity and duration of the tornado season. But, scientific studies show that this is not necessarily to be expected.

Early tornadoes are not unheard of. For example, on February 29 in 1952, two tornadoes caused severe damage in the south-eastern US. But this year, the number of early tornadoes has been much higher. The National Oceanic and Atmospheric Administration reported that in January of 2012, the tornado total was 95, much higher than the 1991–2010 average of 35. And the five-day total for February 28 to March 3 could rank as the highest ever since record-keeping began in 1950, according to meteorologist Dr. Jeff Masters, co-founder of the Weather Underground. With such a record-breaking start, it is not surprising people worry that a more severe 2012 storm season is ahead, and that global warming is to blame.

Tornadoes form when warm and moist air from the Gulf of Mexico meets with very cold and dry air above, which was brought south from the arctic. The collision of these air masses, which have different densities, as well as speeds and directions of motion, forces them to want to switch places very rapidly. This creates updrafts of warm and wet air, which produce thunderstorms. And, as the updrafts climb through the atmosphere, they encounter fast- moving jet stream winds, which change speed and direction with altitude. These changes give the updraft a strong twisting motion that spawns tornadoes.

The severity of tornadoes is rated on the Fujita Scale, which examines how much damage is left after a tornado has passed: F0-F1 tornadoes produce minor damage and so are considered weak, F2-F3 tornadoes produce significant damage and are considered strong, and F4-F5 tornadoes produce severe damage and are considered violent. The problem with this ranking is that it is related to a human-based assessment of damage; you need something (buildings, vegetation, etc.) to be destroyed and someone to see the damage. So, a severe tornado that occurs somewhere where there is nothing to be destroyed would be classed as weak, and one that occurs where there is no-one to see the damage wouldn’t even be counted.

National Oceanic and Atmospheric Administration's VORTEX-99 team observed several tornadoes on May 3, 1999, in central Oklahoma. The tube-like funnel is attached at the top to a rotating cloud base and surrounded by a translucent dust cloud near the ground. Image credit: NOAA.

Still, tornado awareness and volunteer reporting programs, along with good record-keeping, have significantly improved our understanding of tornadoes and their frequency. Surprisingly, the Storm Prediction Center’s tornado database, which goes back to 1950, does not show an increasing trend in recent tornadoes. This finding is confirmed by Dr. Stanley Changnon from the University of Illinois at Urbana-Champaign, whose study of insurance industry records was published last year. Dr. Changnon’s work shows that tornado catastrophes and their losses peaked in the years between 1966 and 1973, but have shown no upward trend since that time. In fact, the number of the most damaging storms, those rated as F2 to F5 has actually decreased over the past 5 decades. So, it does not appear that global warming is increasing the number of tornadoes that occur.

This is actually not as surprising as it seems. While a local increase in temperature and humidity, whether caused by global warming or not, would be expected to create more thunderstorms, it is not clear that these thunderstorms would spawn tornadoes. The reason is that global warming does not increase temperatures the same everywhere. Warming at the poles is expected to exceed warming at more southern latitudes. This means that cold polar air will be much less colder than before and warm Gulf of Mexico air will only be slightly warmer. When these two air masses meet above the southern US, the temperature difference between them will not be so great and their drive to swap places will be much less intense. The result will be a significantly slower moving updraft of warm air that is not expected to produce as many extreme thunderstorms or spawn as many tornadoes.

So, global warming is not expected to increase the total frequency of tornado activity. However, warming global temperatures will mean an earlier spring and the potential for earlier tornadoes. In fact, the early tornado numbers we’ve seen so far this year may be a sign of a global warming-induced shift in the tornado season, according to Dr. Masters. If this is the case, the tornado season may start earlier, but it will also end earlier. As meteorologist Harold Brooks from the National Severe Storms Laboratory in Norman, Oklahoma, points out, this record start to the 2012 tornado season does not necessarily mean the rest of the season will be severe.

Sources:
Recap of deadly U.S. tornado outbreak February 28-March 3, 2012, M. Daniel, EarthSky Mar 5, 2012.
NASA Earth Observatory, March 5, 2012.
Temporal distribution of weather catastrophes in the USA, S.A. Changnon, Climatic Change 106 (2), 129-140, 2011, doi: 10.1007/s10584-010-9927-1.
Does Global Warming Influence Tornado Activity? Diffenbaugh et al., EOS 89 (53), 553-554, 2008.

Posted on by Amy Shira Teitel

ALPHA Closes in on Antimatter

What matter and antimatter might look like annihilating one another. Credit: NASA/CXC/M. Weiss

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We live in a universe made of matter. But at the moment of the Big Bang, matter and antimatter existed in equal amounts. That antimatter has all but disappeared suggests that nature, for some reason, has a strong preference for matter. Physicists want to know why matter has replaced its antimatter twin, and this week the ALPHA collaboration at CERN got a step closer to unraveling the mystery. 

ALPHA, an international collaborative experiment established in 2005, was designed to trap and measure antihydrogen particles with a specially designed experiment. It’s picking up where its antimatter-searching predecessor, ATHENA, left off. The focus is on antihydrogen because hydrogen is the most prevalent element in the universe and its structure is extremely well known to scientists.

Each hydrogen atom has one electron orbiting its nucleus. Firing light at the atoms excites the electron, causing it to jump into an orbit further away from the nucleus before it relaxes and returns to its resting orbit emitting light in the process. The frequency distribution of this emitted light is known; it has been precisely measured and, in our universe made of matter, is unique to hydrogen.

An illustration of hydrogen and antihydrogen. Credit: USAF

Basic physics dictates that hydrogen’s antimatter twin, antihydrogen, should be equally recognizable by having an identical spectrum. That is, if everything we know about particle physics is right. Capturing and measuring antihydrogen’s spectrum is the main goal of the ALPHA group.

ALPHA has taken the first modest measurements of antihydrogen. In the ALPHA apparatus, antihydrogen is trapped by an arrangement of magnets that affect the magnetic field of the atoms. Microwaves tuned to a specific frequency aimed on these antihydrogen atoms flips their magnetic orientation, liberating them. The freed antihydrogen meets hydrogen as it escapes and the two annihilate one another, leaving a well known pattern in particle detectors surrounding the apparatus.

The apparatus captured evidence of the electron jumping orbits in an antihydrogen atom after microwave radiation changed its internal state. The result further proves the validity of ALPHA’s approach, demonstrating that the apparatus has enough control and sensitivity to successfully carry out the experiment it was designed for. In the future, ALPHA will focus on improving the precision of its microwave measurements to uncover the antihydrogen spectrum using lasers.

The exciting results were hard to come by as antihydrogen does not exist in nature. It’s made in the ALPHA apparatus from antiprotons that are themselves made in the Antiproton Decelerator and positrons from a radioactive source. And it has to have a low enough energy level to stay trapped for measurements. But it’s working, and it just might give physicists the key they need to understand the mystery of the early universe.

Source: CERN

Posted on by Jason Major

Still Concerned About 2012?

Don’t be.

Don Yeomans, senior research scientist at NASA’s Jet Propulsion Laboratory in Pasadena, CA, was kind enough to address some common questions regarding 2012, such as the much-misunderstood Mayan “long-count” calendar, Nibiru, pole-reversal and other such purported “doomsday” devices. Check it out.

Still set on the world ending come Dec. 21?

Back off, man. Don’s a scientist.

Posted on by Jason Major

Active Region Is Still Active!

Aurora over Faskrudsfjordur, Iceland on March 8, 2012. © Jónína Óskarsdóttir.

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Even though the CME unleashed by active region 1429 initially hit Earth a bit softer than expected yesterday (read why here), it ended up gaining some extra “oomph” once the magnetic fields lined up right… enough to ignite some amazing displays of aurorae like the one shown above over Iceland, photographed by Jónína Óskarsdóttir!

And that wasn’t the last we’d hear from AR1429 either; at around 10:30 pm EST on March 8, the region lit up again with an M6.3 flare… although smaller than the previous X5.4-class flare, it produced a temporary radio blackout and released another Earth-directed CME, which is expected to arrive in the coming hours.

Dr. Alex Young, solar physicist at NASA’s Goddard Space Flight Center, reported this morning on his blog The Sun Today:

The flare produced a temporary radio blackout as well as a possible Earth directed CME. We will have to wait and see. The sunspot group still shows potential for more activity as the region sits near the central meridian of the Sun. Facing directly at Earth this is a prime location to produce more geo-effective solar activity.

Here is a look at the flare captured by the 131 Angstrom wavelength camera on the Solar Dynamics Observatory (SDO). This shows us the super hot 5-10 million degree plasma produced by the solar flare.

M6.3-class flare from AR1429. (NASA/SDO/AIA team)

Dr. Young also noted that bright aurorae could be visible in lower latitudes as a result of the latest CME, expected to impact Earth at 1:50 am EST:

Aurora watchers at higher latitudes such as the northern US should keep their eyes out in the early morning and maybe even into tonight depending upon how this storm progresses. 

Many times the size of Earth, active region 1429 has been the source of at least five significant flares over the past week. As it moves across the face of the Sun, its shape has become more and more complex — a sure sign, notes Dr. Young, that magnetic forces within it are twisting further and further towards a breaking point. And when they snap, there’s a flare.

“It’s interesting, they kind of look like a mole,” Dr. Young said during an interview on March 8. “And when you monitor a mole, they tell you as long as it stays in a nice symmetric shape and it doesn’t become really complicated and complex, it’s okay. It’s the same sort of thing with sunspots… when they become complicated and twisted, then that mean the magnetic fields inside of them have become more twisted, like a rubber band twisting around until little knots pop up in it. And right now we have been monitoring that sunspot and it is getting more complex.”

(See a photo of AR1429 taken from New Mexico!)

As far as the effects we see here on Earth are concerned, that’s all about the resulting CME — the enormous cloud of charged solar particles that gets blown out into the Solar System. If that cloud impacts Earth’s magnetic field, and if the direction of the cloud happens to be opposite the direction that Earth’s magnetic field is pointed, a lot of energy is “pumped into” our magnetosphere, resulting in a geomagnetic storm.

AR1429 (NASA/SDO/HMI Intensitygram)

During yesterday’s CME impact the Earth’s magnetic field was pointed north — the same direction as the CME. As a result much of the solar material simply flowed along and over it. But the wake ended up getting caught up in the south-directed part of the field, ramping up the energy index (measured as Kp) as the hours progressed. As yet there’s no way to know for certain how a particular CME will align with Earth’s magnetic field.

According to physicist Dr. Philip Scherrer of Stanford University, “we still need better — or perhaps faster — models” to be able to accurately predict the orientation of incoming CMEs. “We are perhaps a few years of research away from completing the picture.”

Currently the geomagnetic storm level is at G3, which according to the NOAA’s Space Weather Scale could result in voltage problems on power systems, increased drag on satellites and “intermittent satellite navigation and low-frequency radio navigation problems… and aurora has been seen as low as Illinois and Oregon.”

So keep an eye out for northern lights in tonight’s skies, and stay tuned for more updates!

Thanks to Dr. Alex Young  for the information! You can follow him on Facebook and Twitter and on his personal blog The Sun Today. Also thanks to Dr. Phil Scherrer at Stanford University and SpaceWeather.com for the heads-up on Jónína’s photo. See more of her aurora photography here. (Used with permission.)

Posted on by Nancy Atkinson

Incredible Digital Re-creations of the Mars Rovers

An incredibly detailed 3-D model of the Spirit rover. Credit: Nick Sotiriadis

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Want to see the Mars Exploration Rovers in incredible, intricate detail – without having to travel to the Red Planet to inspect them in person? Design wizard Nick Sotiriadis from Greece has spent five years working on what he calls a once-in-a-lifetime project creating high resolution 3-D renders of the Mars rovers with attention to detail precise at the scale of millimeters. Even NASA doesn’t have anything this detailed for reference, so Sotiriadis basically built these visual representations of the rovers with 3-D computer graphics.

“After 3 computer upgrades, a lot of sleepless nights, a lot of frustration and hundreds cups of coffee, the project is about to be finished,” Sotiriadis said.

Rendering of the Alpha Particle X-ray Spectrometer (APXS) on the Mar Rover. Credit: Nick Sotiriadis

He’s still putting the final touches on his project, but it’s been a labor of love because of his interest in space and technology, as well as wanting to refine his computer graphic skills.

“It has been really challenging and has helped me increase my experience in the 3-D field,” Sotiriadis told Universe Today. “However, it was a lot tougher than I thought it was going to be. I didn’t have any good references and I spent literally hundreds of hours studying reference photos online. Later on I posted on the Unmanned Spaceflight Forum and people’s support and excitement in the forum is what has kept me going.”

What he is creating are 2-D images with 3D photorealistic effects. Sotiriadis has ‘built’ just the Spirit rover, but said the differences in the two rovers would be visible only to professionals and hardcore fans.

The project is still a work-in-progress, since he is still texturizing and rendering his visualizations, but he has posted several views on his website.

“Once I am finally done the whole page will be replaced with full-high resolution renders of the Mars rovers,” he said.

A close-up of the underside of the Spirit Rover. Credit: Nick Sotiriadis

When the project is complete, viewers will be able to see the rovers in any view. “Since it’s created in 3-D, you can see any angle you want, but it takes several tens of hours of computer processing for the final picture to be created.”

I asked Sotiriadis if since these are super-high resolution re-creations of the rovers, if you printed them out would they basically be life sized — or bigger?

“Since the model is done at that level of detail I can create a picture of any resolution -no matter how high – so I guess it could be created so to be printed in life-size specs and still have all the details,” he said. “However the rendering process – that is the process of creating the photorealism out of my 3-D model – is very power hungry and time consuming. I guess render computer farms would have to be used to make it.”

A different angle view of the Spirit rover. Credit: Nick Sotiriadis

Interestingly, he started this project because of the movie, “Transformers.”

“Ever since I can remember, I loved Transformers,” Sotiriadis said via email. “I played a lot with Transformers when I was a kid. When the movie by Michael Bay was announced, they released a teaser trailer that showed a rover finding robotic life on the Moon. I wanted to do something that was similar to the computer graphics in the movie, so I thought it would be a great idea to model the Mars rovers.”

The five years of work have not come without frustration. “I have redone many things countless times,” Sotiriadis said. “I accidentally deleted surfaces it took tens of hours to re-create, I upgraded my computer several times in order to just open the file because of its great size. The effort was a lot harder than I could ever put to words.”

But it is really awesome.

Check out Sotiriadis’ Mars Rover Project website to see his high resolution renderings of the Mars rovers.

Close-up of the Spirit rover's camera mast. Credit: Nick Sotiriadis
Posted on by Fraser Cain

Most Accurate Clock Ever

An atomic clock; a relic of a bygone age? Image credit: NIST
An atomic clock; a relic of a bygone age? Image credit: NIST

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Do you find that you’re always having to adjust the clocks in your house? Why can’t someone just make a clock that’s accurate? How about a clock that would never lose time in, say, the entire age of the Universe? Well, that’s just what researchers from the University of New South Wales are proposing.

According to their calculations, a neutron orbiting around the atomic nucleus of an atom would do the trick. In fact, this “atomic clock” would be so accurate, it wouldn’t gain or lose 1/20th of a second in 14 billion years – that’s the age of the Universe.

Obviously a clock like this wouldn’t have any value for home use, but in science, accurate clocks are everything. And this single atom clock would be 100 times more accurate than anything scientists have access to right now. They’d be able to record time down to 19 decimal places: 0.0000000000000000001 of a second.

One of the most important places that clocks are used is GPS. The Global Positioning System uses clocks to time how long signals take to reach your GPS unit from various satellites. The satellites are broadcasting very accurate times, which can then be used to triangulate your position. More accurate clocks mean more accurate position.

So how exactly would they do it? Lasers, of course. All the cool science is done with lasers. According the researchers:

“Atomic clocks use the orbiting electrons of an atom as the clock pendulum. But we have shown that by using lasers to orient the electrons in a very specific way, one can use the orbiting neutron of an atomic nucleus as the clock pendulum, making a so-called nuclear clock with unparalleled accuracy.”

Here’s the trick. The neutron of an atom is so tightly bound to the nucleus that it’s almost completely unaffected by outside forces. Electrons, on the other hand, can be affected and so the clocks can be less accurate.

Source: UNSW News Release

Posted on by Nancy Atkinson

Astrophoto: Stunning Detailed Look at the Whirlpool Galaxy by John Chumack

A 17.5 hour exposure of M51, The Whirlpool Spiral Galaxy also known as NGC-5194. Credit: John Chumack

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Wow! Astrophotographer John Chumack has done it again with a spectacular, long exposure view of the Whirlpool Galaxy, M51. “This is my best and most detailed image of M51 to date, and now my longest exposure on a single object,” John said. “Definitely a lot of work, but I now feel it was worth all the processing time, which actually exceeded the 17.5 hours of imaging time!”

Visible are faint tidal tail structure details. “I can see several dust lane structures running through the tidal tail as well as faint background galaxies behind the tidal tail!” John said.

This long exposure image was taken over seven separate nights in early 2010, 2011 with John’s homemade 16″ F4.5 Newtonian Scope. See more details below, or on Flickr. You should also check out John’s website, Galactic Images, where you can see all his beautiful handiwork.

John used a QHY8 Cooled CCD camera and a modified Canon Rebel Xsi DSLR camera. Data from both cameras were used, and both employed a celestron coma corrector and Astronomiks CLS filter employed.

Calibrated Bias, Darks, Flats, Darks for flats, in Deep Sky Stacker via Sigma Reject, both camera data sets were combined and resized to match in Maxim DL, initially color balanced in Nebulosity, Gradient XT was used to remove Light pollution Gradients, Luminance Layered and final color balance in Adobe.

The Whirlpool Spiral Galaxy is actually two colliding Galaxies in the Constellation of Canes Venatici, and can be found a few degrees from the end star in handle of the Big Dipper. The smaller companion that M51 is colliding with is called NGC-5195. M51 sits at 23 million light years away from Earth.

Thanks John!

Want to get your astrophoto featured on Universe Today? Join our Flickr group, post in our Forum or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Posted on by Nancy Atkinson

Weekly Space Hangout — March 8, 2012

In this episode of the Weekly Space Hangout, we talk about two different asteroid close passes, the solar storms buffeting the Earth, a recent space exploration conference, and a team of amateur astronomers flashing the space station. The regular team was there, with Phil Plait, Pamela Gay, Emily Lakdawalla, Alan Boyle, Nancy Atkinson and host Fraser Cain.

We were also joined by Ryan Kobrick – Executive Director of Yuri’s Night – to talk about the upcoming festivities on April 12.

Remember, we record this show live every Thursday at 10:00am PST / 1:00 pm EST / 1800 UTC. Join us at Cosmoquest Hangouts, or watch Fraser’s Google+ stream for the show to start.

Posted on by Jason Major

Playing With Water… in Space!

Expedition 30 astronaut and chemical engineer Don Pettit continues his ongoing “Science off the Sphere” series with this latest installment, in which he demonstrates some of the peculiar behaviors of thin sheets of water in microgravity. Check it out — you might be surprised how water behaves when freed from the bounds of gravity (and put under the command of a cosmic chemist!)

See more Science off the Sphere episodes here.

Posted on by Nancy Atkinson

Radar Prototype Begins Tracking Down Space Junk

Simulation of how Space Fence will track orbital space debris. Image courtesy Lockheed Martin

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Several times a year, the International Space Station needs to perform Debris Avoidance Maneuvers to dodge the ever-growing amount of space junk hurtling around in Earth orbit. Additionally, our increased dependence on satellites for communications and navigation is threatened by the risk of potential collisions with space debris. The existing system for finding and tracking objects, the Air Force Space Surveillance System, or VHF Fence, has been in service since the early 1960s, and is sorely out of date. But a prototype system called Space Fence has now been tested in a series of demonstrations, and successfully tracked more and smaller pieces of debris than the current system.

“The current system has the ability to track about 20,000 objects,” Lockheed Martin spokesperson Chip Eschenfelder told Universe Today, “but there millions of objects out there, many of which are not being tracked. Space Fence will find and catalog smaller objects than what are not being tracked now.”

Space Fence will use powerful new ground-based S-band radars to enhance the way the U.S. detects, tracks, measures and catalogs orbiting objects and space debris with improved accuracy, better timeliness and increased surveillance coverage, Lockheed Martin said. In recent tests, the Space Fence prototype proved it could detect more and smaller objects than the current system.

Space debris includes non-operational satellites, and leftover rocket parts from launches. Basically, every time there is a launch, more debris is created. Collisions between the current debris create even more pieces that are smaller and harder to detect. With the debris traveling at lightning-fast orbital speeds, even pieces as small as a paint chip could be deadly to an astronaut on EVA at the space station, or could take out a telecommunications or navigation satellite.

A look at the Space Fence control center. Credit: Lockheed Martin

The developers of Space Fence say the new system will revolutionize what’s called ‘space situational awareness,’ which characterizes the space environment and how it will affect activities in space.

“Space Fence will detect, track and catalog over 200,000 orbiting objects and help transform space situational awareness from being reactive to predictive,” said Steve Bruce, vice president of the Space Fence program. “The Air Force will have more time to anticipate events potentially impacting space assets and missions.

The current system has tracking locations in the US only and has a huge ‘blind spot’ by not supplying information about debris in the southern hemisphere. But Space Fence will provide global coverage from three ground-based radar located at strategic sites around the world.

On February 29, 2012, the Air Force granted its final approval of Lockheed Martin’s preliminary design, and they expect the new system’s initial operational capability to be sometime in 2017.

“The successful detection and tracking of resident space objects are important steps in demonstrating technology maturity, cost certainty and low program risk,” said Bruce in a statement. “Our final system design incorporates a scalable, solid-state S-band radar, with a higher wavelength frequency capable of detecting much smaller objects than the Air Force’s current system.”

For more information see the Space Fence website, and NASA’s Orbital Debris Program Office.