Is it possible to terraform Mars?
Think of Mars as a massive fixer-upper. Sure, it's nowhere nearly as nice as our current planetary home, but perhaps with a little work we could live there. Given enough time and effort, can we one day terraform the red planet and turn it into a new Earth? Or is Mars nothing but a hopeless money pit in the sky?
As with any prospective homebuyer, we really need to look at what's broken and what it will take to fix everything. Curb appeal aside, two key shortcomings prevent Mars from being move-in ready.
First up, the terrible atmosphere. Humans are pretty picky when it comes to atmospheric conditions. If the pressure's too high or too low, we die. If we don't get enough oxygen, we die. After all, we've evolved to live within a very specific layer of Earth's gaseous outer layer. Mars' atmosphere is very thin and incredibly cold. It lacks sufficient air pressure and contains way too much carbon dioxide.
Second, if you're looking to move into a new planet, make sure there's an intact electromagnetic field. Earth has one, generated by hydrodynamic convection between its liquid outer core and solid inner core. Without this shielding, we'd be exposed to a deadly stream of highly charged particles called the solar wind. For reasons we don't entirely understand yet, Mars lacks this protection and possesses only remnants of a magnetic field at its polar ice caps.
It gets worse. According to a 2010 study from the Swedish Institute of Space Physics and the University of Leicester, double solar radiation waves periodically strip away 30 percent of the sparse Martian atmosphere. These waves occur when one solar wave overtakes another to produce a single, more powerful wave. What little atmosphere remains is due to comet strikes and the occasional melting of polar ice.
So what would it take to fix Mars up to Earthling standards? Scientists have made various proposals to induce a greenhouse effect on Mars through the use of mirrors, atmosphere factories or asteroid impacts. We could melt the polar ice caps to release trapped carbon dioxide or generate greenhouse gases in factories. In time, we could theoretically start using widespread atmosphere factories to turn carbon dioxide into oxygen in a manner similar to plants.
All of this tinkering might thicken up the atmosphere and provide greater radioactive shielding, but Mars will continue to face atmosphere loss due to double solar radiation waves. There's no getting around the fact that Mars desperately lacks an electromagnetic field.
Scientists disagree on the makeup of Mars' modern core. It might be solid, liquid or some combination of the two. It all depends on which scientist you talk to and which study they choose to support. Whatever the truth is, we know something isn't working down there. A 2008 University of Toronto study theorized that, more than 4 billion years ago, incoming asteroids applied a gravitational tug to liquids in Mars' core, producing enough of a dynamo effect to generate a temporary electromagnetic field. Could the introduction of a new, artificial moon give the core the kick-start it needs?
Other proposals involve injecting Mars' core with radioactive waste to fire it up, while other scientists think artificial magnetic fields may be the answer.
Mars is quite the fixer-upper. Even the best-case scenarios entail centuries of renovating, and the technology to induce or recreate electromagnetic field protection may be centuries off as well.
Explore the links on the next page to learn even more about Mars.
The Atmosphere of Mars
Of all the planets, Mars is our closest relation in terms of makeup (not distance), but that's not saying much. And it certainly doesn't mean that the red soil is hospitable. The atmosphere of Mars differs from the Earth's in many ways, and most of them don't bode well for humans living there.- It's composed mostly of carbon dioxide (95.3 percent compared to less than 1 percent on Earth).
- Mars has much less nitrogen (2.7 percent compared to 78 percent on Earth).
- It has very little oxygen (0.13 percent compared to 21 percent on Earth).
- The red planet has about 1/1000 as much water vapor (0.03 percent).
- It exerts only 7 millibars of pressure (Earth's atmospheric pressure is 1,000 millibars).
Because the "air" on Mars is so thin, it holds little heat. Most of the heat comes from the ground after it absorbs solar radiation. The thin air also is responsible for the wide, daily swings in temperature (almost 100 degrees Fahrenheit or 60 degrees Celsius). Martian atmospheric pressure changes with the seasons. During the Martian summer, carbon dioxide sublimes from the polar ice caps into the atmosphere, thereby increasing the pressure by about 2 millibars. During the Martian winter, carbon dioxide refreezes and falls from the atmosphere (carbon dioxide snow!), thereby causing the pressure to decrease again. Finally, because the Martian atmospheric pressure is so low and the average temperature is so cold, liquid water cannot exist; under these conditions, water would either freeze or evaporate into the atmosphere.
The weather on Mars is pretty much the same each day: cold and dry with a chance of storms -- dust storms, that is. Light winds blow from one direction in the morning and then from the reverse direction in the evening. Clouds of water ice hover at altitudes of 12 to 18 miles (20 to 30 kilometers), and clouds of carbon dioxide form at approximately 30 miles (50 kilometers). Because Mars is so dry and cold, it never rains. That's why Mars resembles a desert, much like Antarctica on Earth.
During the spring and early summer, the sun heats up the atmosphere enough to cause small convection currents. These currents lift dust into the air. The dust absorbs more sunlight and heats the atmosphere further, causing more dust to lift into the air. As this cycle continues, a dust storm develops. Because the atmosphere is so thin, great speeds (60 to 120 mph or 100 to 200 kph) are required to stir up the dust. These dust storms spread across large regions of the planet and can last for months. You might think all the dust would be bad for the rovers traversing the surface, but the storms actually can clear off the dirt caked on their solar panels.
Photo courtesy NASA Jet Propulsion Laboratory (NASA-JPL)
The photo on the left shows a dust storm brewing at about the 4 o'clock position and in the northern polar cap. Two months later, the planet's features are totally obscured by the dust.
Dust storms are also thought to be responsible for the variable dark regions on Mars that are seen from ground-based telescopes, which were mistaken for canals and vegetation by Percival Lowell and others. The storms are also a major source of erosion on the Martian surface.
Telescope's
Hubble Space Telescope
NASA/National Geographic/Getty Images
The Hubble Space Telescope has provided unparalleled images of space.
No matter how big ground-based telescopes get, they will always face the issue of distortion caused by Earth's atmosphere. A smaller telescope deposited in space, beyond Earth's atmosphere, can avoid the issue entirely. The Hubble Space Telescope combines astronomy with rocket science and operates in Earth's orbit.
With an aperture of 2.4 meters (94.5 inches), Hubble is much smaller than state-of-the-art ground telescopes, but its resolution is comparable or better, since the light it collects has travelled only through the relative vacuum of space [source: Hubblesite.org]. Hubble captures faint light coming in from billions of light years from Earth, which means it can see events that occurred billions of years ago. Hubble helped scientists confirm that dark matter exists and narrow down the age of the universe to 13 or 14 billion years [source: Hubblesite.org].
Hubble captures incredible images of the universe, but it's not the best space telescope out there. The Chandra X-ray Observatory tops Hubble in revealing the hidden world.
Chandra X-ray Observatory
NASA/CXC/MIT/F.K.Baganoff/Getty Images
The Chandra X-ray Observatory created this image of the event horizon of a super-massive black hole. The exposure lasted two weeks.
X-ray telescopes rely on higher-energy phenomena than light telescopes. Chandra records images of the universe by analyzing energy fluctuations on the level of X-rays, using a barrel-shaped series of mirrors that make up a total aperture of 2.7 meters (9 ft) [source: Harvard]. Because the images are based on much higher-frequency waves of energy, they're clearer than Hubble's, and Chandra is a more sensitive instrument -- 25 times more sensitive than any other X-ray telescope [source: Harvard]. It also orbits Earth 200 times farther out than Hubble, so it's able to see deeper into space, peering out about 10 billion light years from Earth.
Chandra X-ray observatory has recorded crystal clear images of supernova remnants, quasars, exploding stars, black holes, nebulae and dark matter, among other phenomena. Scientists believe that Chandra will make startling contributions to our understanding of the origins of life.
Chandra is certainly not the last word in space telescopes. The Next Generation Space Telescope is already in development. It will orbit the sun, not the Earth, and it could be launched by 2013 [source: FirstScience]. And like the space telescopes, ground-based devices are looking at a next generation, too.
The current state-of-the-art instruments are in the 8-to-10-meter (26.25-to-32.81-ft) aperture class. The next wave of telescopes will squash that. The race is on to build the biggest telescope ever, and the final three telescopes on our list are top contenders.
European Extremely Large Telescope
At a cost of $1.17 billion, the European Extremely Large Telescope (ELT) is aiming high. The Chile-based project, funded by a consortium of European Union countries, is building a telescope with a 42-meter (138-ft) mirror. The original design called for a 100-meter (330-ft) mirror but was downsized for practical reasons.
Still, 42 meters is nothing to sneeze at. This new class of telescope -- the 30-to-50-meter class -- is only possible because engineers have come up with new ways to build mirrors. The number of segments they can piece together into a perfect surface has grown from the dozens to the hundreds, meaning the possibilities of what these new telescopes can see is nearly endless.
As for the ELT, astronomers are predicting the discovery of new planets and entire planetary systems, as well as revealing the events that gave birth to the universe. As early as 2018, the 21-story-tall telescope should add dramatically to our knowledge across the field of astrophysics, providing insight into dark matter and dark energy, the space-time continuum and the inner workings of super-massive black holes.
With both private and public sources pumping hundreds of millions of dollars into telescopes, our ability to see into the farthest corners of the universe -- and into the farthest corners of time -- appears to be limited only by how quickly we can build bigger instruments. No one knows just what we'll see when the next-generation ground- and space-based telescopes start delivering their images.
For more information on telescopes, including upcoming projects and details on how these and other telescopes work, look at the links on the next page.
Still, 42 meters is nothing to sneeze at. This new class of telescope -- the 30-to-50-meter class -- is only possible because engineers have come up with new ways to build mirrors. The number of segments they can piece together into a perfect surface has grown from the dozens to the hundreds, meaning the possibilities of what these new telescopes can see is nearly endless.
As for the ELT, astronomers are predicting the discovery of new planets and entire planetary systems, as well as revealing the events that gave birth to the universe. As early as 2018, the 21-story-tall telescope should add dramatically to our knowledge across the field of astrophysics, providing insight into dark matter and dark energy, the space-time continuum and the inner workings of super-massive black holes.
With both private and public sources pumping hundreds of millions of dollars into telescopes, our ability to see into the farthest corners of the universe -- and into the farthest corners of time -- appears to be limited only by how quickly we can build bigger instruments. No one knows just what we'll see when the next-generation ground- and space-based telescopes start delivering their images.
For more information on telescopes, including upcoming projects and details on how these and other telescopes work, look at the links on the next page.
Animals: Polar Bear Cubs in Big Trouble
As sea ice decreases in both coverage, thickness and age, polar bears could have fewer cubs, according to new research. Jorge Ribas reports on the findings from the Arctic.
Animals: New Species Discovered in Papua New Guinea
More than 200 new species of insects, amphibians and mammals were recently found in the rainforest of Papua New Guinea. So how were all these animals discovered? Conservation International scientists explain their techniques.
Jerusalem UFO Video: Case Closed
In January of this year, a series of videos showing what appeared to be a UFO hovering over Jerusalem’s Dome of the Rock caused a stir. As Discovery News space producer Ian O’Neill wrote, "The footage shows the light drop and seemingly hover just above the shrine. After a few moments, and a brief flash of a strobe, the light took off, disappearing into the night sky. Videos have surfaced of the event and have since gone viral on YouTube."
Based upon my experience investigating images of UFOs and other "unexplained" phenomena, O'Neill asked for my analysis. I researched both the video and the circumstances surrounding it, and provided a list of reasons why I concluded that the videos were "almost certainly a hoax."
The reaction among UFO believers was both swift and dismissive. O'Neill's column on the topic generated more reader comments than any other at the time, and remains one of the most-commented pieces to date. The post soon made it to CBS News.com, where it generated even more controversy, with nearly 100 posters there commenting on my analysis of the video. Some expressed reservations about the authenticity of the video, but the vast majority dismissed my analysis and claimed that the video was authentic.
My skeptical explanations were ridiculed as biased and uninformed. Typical comments included: "Multiple witnesses, different video angles from different nationalities. If it is a hoax, then it would be the best of all hoaxes. I believe it is real..."; "that was the most lame explanation for these videos being a hoax..."; "I am really growing tired of you idiots attempting to debunk UFOs with your casual investigations..."; and "This is a PROPAGANDA article. People realize the truth! I wish this was a hoax. This is the unknown."
Others called my analysis "classic uninformed debunking," and stated, "Mr. Radford, if you're going to make assertions without doing your homework, then you show nothing but your ignorance." Several posters requested a follow-up: “If Ian O'Neill would comment with some follow-up research and/or analysis, then it would help restore any faith some people may have lost in his journalistic ability."
I'm not even remotely concerned about O'Neill’s journalistic ability, but I am happy to present the conclusion of an independent follow-up analysis: It's a hoax.
A few days ago, the Mutual UFO Network (MUFON), one of the oldest, largest, and most respected UFO investigation organizations in the world, announced their findings about the Jerusalem UFO. MUFON, though hardly a hard-line skeptical organization, has a stable of experts they draw upon for analysis.
According to a statement, "MUFON's chief Photo and Video Analyst, Mr. Marc Dantonio, stated 'I firmly believe that the UFO was not real, for many reasons...this video and the other Jerusalem UFO Videos are in my opinion hoaxes." Dantonio cited several reasons for his conclusion, some of them echoing points I made in my analysis published in O'Neill's piece six weeks earlier.
It seems that the skeptical analysis was correct after all: The Jerusalem UFO video was a hoax. This of course puts many UFO believers in an awkward position -- unless they assume that the world's largest UFO-promoting organization is also part of the effort to cover up evidence for UFOs...
Moms' Junk Food Habits May Alter Kids' Brains
photo: iStockPhoto
Pregnant or breast-feeding women may inadvertently pass poor eating habits along to their children, a new study reports.
An experiment conducted in rats shows that females eating diets dense with fats and sugars while pregnant or lactating ended up with offspring with similar food preferences. Given the biological similarities between humans and other mammals, scientists suspect this might be true for us as well.
NEWS: Binging Rats Get Hooked on Junk Food
Featured in The Federation of American Societies for Experimental Biology Journal, the research bases its findings on the notion that mom's diet can alter the neurological reward pathways in baby's brain.
Essentially, these eating habits alter how babies approach eating in early -- and perhaps later -- stages of life.
In the experiment, one group of pregnant and lactating rats consumed nutritious rat chow, while another group ate certain human foods high in fat and sugar.
PLANET GREEN: Junk Food Deconstructed
When the rats' offspring were six weeks and three months of age, scientists gave them the choice of eating regular food (the chow) or the same "junk food" certain mothers ate.
Rat pups whose mothers binged on fatty and sugary foods were more likely to prefer similar foods when compared to rats born from mothers with regular diets.
NEWS: Junk Food Studies Ignore Parent Responsibility
To measure any physiological differences, researchers euthanized certain individuals from each group to study their brain tissues. The research team discovered changes in mu opioid receptors and dopamine transporters of the brain -- areas important to reward pathways.
These are the same areas "feel-good" chemicals such as dopamine maneuver through.
This isn't to say all junk food should be forbidden from pregnant women or those who are breast-feeding, but it certainly supports the idea of moderation.
The research fits into the larger context of prenatal care, supporting women eating healthily and taking specific vitamin supplements to promote normal fetal development, according to the Mayo Clinic.
