Looking for life, Astrobiologists Dive Deep
NASA Astrobiology Magazine | News | 07 Feb 2001
Viruses Stay LocalSummary: Coral-like mounds on the floor of a Canadian lake may make it easier someday to identify life on other planets.
based on NASA Ames release 00-67AR
A team of interdisciplinary astrobiologists from NASA and other agencies is homing in on recognizing the microbial biosignatures for life, making it easier someday to identify life on other planets.
A scientific paper analyzing the team's research results, titled "Modern Freshwater Microbialite Analogues for Ancient Dendritic Reef Structures," was published in the journal Nature on October 5. The paper focuses on the study of mounded microbialite deposits layers of living and non-living organisms found at Pavilion Lake in Canada.
NASA Astrobiology Magazine | News | 08 March 2008
Looking for Life on Mars – in a Canadian LakeSummary: Biologists examining ecosystems similar to those that existed on Earth more than 3 billion years ago have made a surprising discovery: Viruses that infect bacteria are sometimes parochial and unrelated to their counterparts in other regions of the globe. It's surprising because bacteria and the viruses that affect them were long believed to be cosmopolitan, having similar genetic histories across the globe.
Based on an Rice University news release
Biologists examining ecosystems similar to those that existed on Earth more than 3 billion years ago have made a surprising discovery: Viruses that infect bacteria are sometimes parochial and unrelated to their counterparts in other regions of the globe.
The finding, published online by the journal Nature, is surprising because bacteria are ubiquitous on Earth. They've been found from the upper reaches of the atmosphere to miles below the ocean floor. Because of their ubiquity, scientists have long believed bacteria to be cosmopolitan, having similar genetic histories across the globe. The same was also believed to be true for phages, the viruses that infect bacteria.
NASA Astrobiology Magazine | Expedition | 08 Sept 2008
Discoveries in the DeepSummary: At first glance, Pavilion Lake, in British Columbia, looks like just another idyllic vacation spot. But beneath its surface lie some of the most unusual carbonate formations on Earth.
On the surface, Pavilion Lake, nestled among the peaks of Canada’s Marble Range, looks like a thousand other mountain lakes. It’s not unusually large or deep. It’s not especially acidic, or alkaline; it’s not overly salty; nor are there high concentrations of minerals dissolved in its water. Locals come here to fish, to boat, to swim, and to watch the summer clouds drift by.
But underwater lies an astonishing discovery that has drawn astrobiologists from around the world to this rural corner of British Columbia. Pavilion Lake is host to an underwater “forest” of microbialites, coral-like structures, in a variety of shapes and sizes, that may help guide the search for life on Mars.
NASA Astrobiology Magazine | Exclusive | 12 Nov 2009
Microbial Life in Mars Analog LakesSummary: Scientists from NASA and the Canadian Space Agency have been using Pavilion Lake as a testing ground for the future human exploration of other worlds.
Pavilion Lake, in British Columbia, Canada, is home to a biological mystery. Microbialites, coral-like structures built by bacteria, in a variety of sizes and shapes, carpet the lakebed. That’s unusual for a freshwater lake like Pavilion. So unusual that researchers don’t know of any other freshwater lake in the world that has microbialites with some of the same strange shapes.
That explains why scientists have established the Pavilion Lake Research Project (PLRP) to study the lake. They want to understand what’s so unusual about seemingly normal Pavilion Lake, how the microbial structures manage to survive, why they aren’t destroyed by snails, worms and other grazing animals, as they are elsewhere.
NASA Astrobiology Magazine | Exclusive | 21 Jan 2010
Probing Pavilion LakeSummary: The first microbiological survey of Mars analog lakes in Western Australia is offering new evidence of the diverse life that could have once thrived on Mars.
The types of environments that exist on Mars and whether or not they are conducive to sustain life are still big mysteries for scientists who study the red planet. Until scientists can study Mars environments first-hand, the next best option is to study Earth environment “analogs” thought to closely resemble Mars.
In a recent study published in the journal Astrobiology, scientists conducted the first microbiological survey of Mars analog lakes in Western Australia. These natural acid saline lakes, the authors say, could be similar in some respects to past Martian environments. They also may represent what conditions were like on Earth billions of years ago.
NASA Astrobiology Magazine | Expedition | 24 June 2010
Flying the North BasinSummary: A team of scientists and astronauts return this week to Pavilion Lake in the Canadian province of British Columbia. The scientists will be continuing their effort to understand what role biology plays in forming the strange structures that line the lakebed, while the astronauts will be learning how to do field science.
“For all intents and purposes,” says Allyson Brady of the University of Calgary, Pavilion Lake, in British Columbia, “seems to be a pretty normal lake. There are fish in it; people have cottages around the lake, you can go swimming.” It’s a lovely place to bring the family for a summer vacation.
But Brady, acting principal investigator of the Pavilion Lake Research Project (PLRP), and her colleagues won’t be vacationing this week when they descend into the depths of the lake, as they have for the past several summers. Despite its pastoral surface appearance, Pavilion Lake is anything but normal. Carpeting the slopes of the lakebed is an underwater forest of carbonate structures that, at first glance, might be mistaken for coral. These carbonate formations – PLRP’s researchers call them “microbialites” – range in size from small nodules the width of a quarter to massive mounds several meters across. Until they were discovered in Pavilion Lake, such formations were relatively unknown in freshwater lakes.
Similar structures are known to exist in a handful of other places in the world, in Shark Bay, Australia, for example, “but these tend to be more extreme environments,” Brady says. “Areas where you don’t find much else living there but bacteria,” because it’s too salty, too acidic or generally too extreme for other life forms to survive. No-one has been able to figure out yet what they’re doing in Pavilion Lake.
NASA Astrobiology Magazine | Expedition | 01 July 2010
On the Beach with the GaviatorsSummary: Astrobiology Magazine’s Henry Bortman is in the field this week alongside members of the Pavilion Lake Research Project (PLRP). The scientists are studying microbialites, carbonate structures that are usually not found in freshwater lakes. This report looks at the complex process of communicating with scientists as they explore underwater.
... One of PLRP’s main activities is the exploration of the lake with a pair of DeepWorker one-person submarines. This is the third year the Deepworkers have been at the lake. On a typical day, two DeepWorker “flights” take place, both subs going out each time.
Pavilion Lake’s microbialites – carbonate structures that are thought to be created by microbes -- come in many sizes and shapes. Last year, the main goal of the DeepWorker flights was to map the entire lakebed, to develop an overview of how different types of microbialites are distributed throughout the lake. This year the missions will focus on specific areas in more detail.
NASA Astrobiology Magazine | Expedition | 03 July 2010
What Do You Call a Microbialite?Summary: Astrobiology Magazine’s Henry Bortman ...(PLRP)... second field report describes the glitches and problems researchers have had to overcome so that their “Gavia” robotic vehicles can explore the lake as planned.
Today I hung out on a pebbly beach with a group of scientists everyone refers to as The Gaviators. They’re named for the Gavia AUVs (autonomous underwater vehicles) they work with. A Gavia AUV looks like a brass-colored torpedo, about 6 feet long and 10 inches in diameter, with a pointed nose at one end and a propeller at the other. In-between are various data-collection modules that can be configured as needed.
Gavia is good for large-scale, comprehensive, repetitive work. It doesn’t get tired, hungry, bored or distracted, and, unlike a DeepWorker pilot, it flies in straight lines. Once it’s programmed, it can run for hours, traversing back and forth across the lake in a “lawnmower” pattern, collecting vast amounts of data without anyone having to worry much about it. When it works.
NASA Astrobiology Magazine | Expedition | 05 July 2010
The Big Question: Biology or Chemistry?Summary: Astrobiology Magazine’s field research editor Henry Bortman ... (PLRP) ... third field report, he discusses the ongoing effort to classify the lake’s microbialites.
... One of the major ongoing projects of PLRP is classifying all the different kinds of microbialites in the lake. Although there are other places in the world where living microbialites exist, Pavilion Lake is distinctive for the diversity of the structures found there.
“Pavilion has, I think, greater morphological diversity than any other modern environment where people are studying microbialites. That’s what makes it so special,” said Rebekah Shepard, a PLRP team member and DeepWorker pilot who did her graduate research in how microbialites form. (Note: the word “morphology” comes up a lot when you talk to people doing microbialite research. It refers to the size and shape of something, its overall form.)
NASA Astrobiology Magazine | Expedition | 15 July 2010
Summary: Astrobiology Magazine’s field research editor Henry Bortman ... (PLRP) ... fourth field report, he discusses work being done to determine the role biology plays in forming the Pavilion Lake microbialites.
The Big Question at Pavilion Lake is this: What role does biology play in forming the microbialites found here? The undisputed fact is that the microbialites are covered in living bacteria. What’s less clear is whether the bacteria influence the formation of the lake’s carbonate structures or the microbialites form though some purely chemical process, with the bacteria merely hanging out in the neighborhood.
As Curtis Suttle of the University of British Columbia pointed out, “There are certain microbes that might like to live in high-carbonate environments, that just happen to grow there, not because they made them but because it’s an environment they like to live in.”