Life is hardier than was thought only a few decades ago. With the help of new exploration technologies and new methods for finding and identifying organisms, our perceptions of what constitute the environmental limits for life on Earth have changed.
You can find life in extreme environments, whether acid or alkaline, hot or cold. Life can be found under high pressure, without free water (in hot and cold deserts), in extremely salty environments (like the Dead Sea), and in areas that lack oxygen or experience high radiation levels.
We now recognize that microbial life can exist in most extreme environments on Earth. So it should not be a surprise that in a study just published in Nature, researchers report the first direct evidence of life in a lake located almost a kilometer below an ice sheet in Antarctica.
Climate records, like tree rings or ice cores, are invaluable archives of past climate, but they each reflect their local conditions. If you really want a global average for some time period, you’re going to have to combine many reliable records from around the world and do your math very carefully.
That’s what a group of researchers aimed to do when (as Ars covered) they used 73 records to calculate a global overview of the last 11,000 years—the warm period after the last ice age that's called the Holocene. The Holocene temperature reconstruction showed a peak about 7,000 years ago, after which the planet slowly cooled off by a little over 0.5 degrees Celsius until that trend abruptly reversed over the last 150 years. That behavior mirrored the change in Northern Hemisphere summer sunlight driven by cycles in Earth’s orbit.
A new study published in the Proceedings of the National Academy of Sciences and led by the University of Wisconsin’s Zhengyu Liu delves into a problem with that pattern—and it’s not what climate models say should have happened.
A Martian pyramid, a modular beehive, and a three-tiered Acropolis have made the final cut in the MakerBot Mars Base Challenge.
Run by Thingiverse and launched in conjunction with the 3D printer maker and Nasa's Jet Propulsion Laboratory, the challenge has been open since May 30 and clocked up 227 applications. The three winning entries will each be awarded a MakerBot Replicator 2 Desktop 3D Printer in order to help them fully explore their designs for Martian abodes.
The challenge brief asked entrants to take into account the extreme weather, radiation levels, lack of oxygen, and dust storms when designing their Martian shelters. And although the applicants did not always nail the science, their designs have a novelty we've not seen since Nasa's 1970s space station and scooter designs.
The Iceland Meteorological Office has increased the risk level of an eruption at the Bárðarbunga (or Bardarbunga) volcano after hundreds of earthquakes were reported over the weekend. The risk level has been set to orange, which is the fourth-highest rating on a five-level scale.
We asked Dave McGarvie, a volcanologist at The Open University, to explain what this means.Should we be worried?
We have known for some time that Bárðarbunga was going to do something—we just didn’t know what. Because it is covered in ice, we rely on instruments to reveal its behavior.
Kim Goodsell was running along a mountain trail when her left ankle began turning inward, unbidden. A few weeks later she started having trouble lifting her feet properly near the end of her runs, and her toes would scuff the ground. Her back started to ache, and then her joints, too.
This was in 2002, and Kim, then 44 years old, was already an accomplished endurance athlete. She cycled, ran, climbed, and skied through the Rockies for hours every day; she was a veteran of Ironman triathlons. She’d always been the strong one in her family. When she was four, she would let her teenage uncles stand on her stomach as a party trick. In high school, she was an accomplished gymnast and an ardent cyclist. By college, she was running the equivalent of a half marathon on most days. It wasn’t that she was much of a competitor, exactly—passing someone in a race felt more deflating than energizing. Mostly Kim just wanted to be moving.
So when her limbs started glitching, she did what high-level athletes do, what she had always done: she pushed through. But in the summer of 2010, years of gradually worsening symptoms gave way to weeks of spectacular collapse. Kim was about to head to Lake Superior with her husband, CB. They planned to camp, kayak, and disappear from the world for as long as they could catch enough fish to eat. But in the days before their scheduled departure, she could not grip a pen or a fork, much less a paddle. Kim, a woman for whom extreme sports were everyday pursuits, could no longer cope with everyday pursuits. Instead of a lakeside tent, she found herself at the Mayo Clinic in Rochester, Minnesota.