Canadians applying weather expertise to Mars
Updated Wed. Aug. 1 2007 7:40 PM ET
Michael Stittle, CTV.ca News
http://www.ctv.ca/servlet/ArticleNe...01/mars_mission2_070801/20070801?hub=Specials
Every Canadian is an expert on winter, and cursing or praising our frigid landscape binds us together. Now our scientists will help NASA study the arctic weather of another planet: Mars.
NASA's Phoenix lander could launch into space this weekend for a 10-month journey to the Red Planet, carrying with it an advanced weather station designed by Canadians.
"I believe it's the first time Canada has ever had an instrument on another planet," Dr. Thomas Duck, a professor of physics and atmospheric science at Dalhousie University, told CTV.ca Wednesday.
The Canadian device includes a pressure sensor, three temperature sensors and a "lidar" -- also written as LIDAR, an acronym for Light Detection and Ranging.
The weather station will help scientists understand the Martian water cycle and climate, radically different from Earth's because it's affected mainly by dust, rather than carbon dioxide.
Duck helped design the lidar, which will bounce light off of any Martian dust particles, fog or clouds in the lower atmosphere.
"It's the optical analog to a radar or a sonar. With a sonar, you drive around in your submarine and you send out pings of sound, and you listen for echoes from other submarines or boats. The delay time between when you send the ping and when you get the echo tells you how far away they are," he explained.
"The lidar is kind of similar, except that we use laser light instead. We send up a pulse of laser light into the atmosphere, and it scatters off of everything up there, such as clouds and aerosols. A little bit of that light reflects right back down towards us, and we collect that light in an astronomical telescope, detect it with very sensitive detectors, and then store that data in the computer for later analysis."
The data will then get beamed back to Earth, giving scientists an idea of how Martian weather works, and how water travels between the planet's atmosphere and its rocky surface.
In a Canadian city, a lidar could be used to detect the amount of pollution staining the atmosphere overhead. But in Mars, largely untouched by humans except for a few machines on the surface and spacecraft floating in orbit, it remains pristine.
But Mars does have an abundance of dust, churning up into massive storms, gathering into dust-weevils, or resting calmly on the surface.
The dust poses a danger to any machines sent to Mars, including NASA's remarkably resilient and still-working rovers, Opportunity and Spirit.
"Mars has these giant dust storms, and there's a really good one going on right now in the equatorial region," said Duck. "They've actually had to shut off the two rovers there because (NASA) is worried about their batteries running out -- they may not have enough sunlight to recharge them."
If Phoenix lands on Martian soil next year, the lidar will have a lid to protect it from the dust. That lid will remain firmly shut until the device starts taking measurements, and can easily close tight again if necessary.
"We just batten down the hatches if there's a dust storm and wait it out," said Duck.
There's so much dust on Mars, it's become a crucial element in the planet's weather formations, influencing how hot the surface gets or how much sunlight reaches the ground.
"In Earth's atmosphere, carbon dioxide is very important for climate. But on Mars, it's actually the dust that's the key thing," said Duck. "So the dust is really what determines temperatures in the Martian atmosphere, and so really determines the climate."
But it's the water that scientists are really looking for. Experts believe Mars once had giant oceans and lakes just like Earth, but now all that's left are the polar caps and possibly some faint clouds.
The great unsolved mystery is where the water went, and studying the current water cycle could offer the answer.
"We're landing at about 70 degrees north, so in the northern plains in the high north of Mars. The ice cap there actually expands and contracts with the seasons, and all of that water from the ice cap has to go somewhere, so we figure there are probably fogs that develop, frost, and there appear to be clouds as well," said Duck.
"We're interested in being able to take measurements of these things and to try and understand this water cycle."
On Earth, clouds break apart and cause rain, which then feeds into rivers and lakes. The sun then evaporates the water, starting the whole process over again as water particles drift upwards and form more clouds.
"On Mars, there just isn't enough water available to do that," explained Duck. "You probably form some clouds, but they're not going to be anywhere near as thick as on Earth, and we don't expect to see precipitation the way that we see it here."
Studying how water moves around on Mars could also give a peak into whether life ever existed on the rocky planet -- or if it still does.
Scientists are not discounting the possibility that somewhere on the Red Planet, organisms are still clinging to life, taking advantage of what little water remains.
"All of our indications are that water is a basic building block of life. So actually going there and detecting water is a really big deal," said Duck.
"With the Phoenix mission, one of its goals is to actually go and touch the water. It will be the first instrument to do that. We have a lot of indirect detections of water from orbiting radars and spectrometers and things like that. But the Phoenix, on the other hand, will actually go and dig under the soil and pick up whatever's there and deposit it into a chemical analyzer. One of the things we'll look for is water, and we'll also look for organic matter."
The next opportunity for Phoenix to blast off from Cape Canaveral, Florida is this Saturday at 5:26 a.m. ET.
Updated Wed. Aug. 1 2007 7:40 PM ET
Michael Stittle, CTV.ca News
http://www.ctv.ca/servlet/ArticleNe...01/mars_mission2_070801/20070801?hub=Specials
Every Canadian is an expert on winter, and cursing or praising our frigid landscape binds us together. Now our scientists will help NASA study the arctic weather of another planet: Mars.
NASA's Phoenix lander could launch into space this weekend for a 10-month journey to the Red Planet, carrying with it an advanced weather station designed by Canadians.
"I believe it's the first time Canada has ever had an instrument on another planet," Dr. Thomas Duck, a professor of physics and atmospheric science at Dalhousie University, told CTV.ca Wednesday.
The Canadian device includes a pressure sensor, three temperature sensors and a "lidar" -- also written as LIDAR, an acronym for Light Detection and Ranging.
The weather station will help scientists understand the Martian water cycle and climate, radically different from Earth's because it's affected mainly by dust, rather than carbon dioxide.
Duck helped design the lidar, which will bounce light off of any Martian dust particles, fog or clouds in the lower atmosphere.
"It's the optical analog to a radar or a sonar. With a sonar, you drive around in your submarine and you send out pings of sound, and you listen for echoes from other submarines or boats. The delay time between when you send the ping and when you get the echo tells you how far away they are," he explained.
"The lidar is kind of similar, except that we use laser light instead. We send up a pulse of laser light into the atmosphere, and it scatters off of everything up there, such as clouds and aerosols. A little bit of that light reflects right back down towards us, and we collect that light in an astronomical telescope, detect it with very sensitive detectors, and then store that data in the computer for later analysis."
The data will then get beamed back to Earth, giving scientists an idea of how Martian weather works, and how water travels between the planet's atmosphere and its rocky surface.
In a Canadian city, a lidar could be used to detect the amount of pollution staining the atmosphere overhead. But in Mars, largely untouched by humans except for a few machines on the surface and spacecraft floating in orbit, it remains pristine.
But Mars does have an abundance of dust, churning up into massive storms, gathering into dust-weevils, or resting calmly on the surface.
The dust poses a danger to any machines sent to Mars, including NASA's remarkably resilient and still-working rovers, Opportunity and Spirit.
"Mars has these giant dust storms, and there's a really good one going on right now in the equatorial region," said Duck. "They've actually had to shut off the two rovers there because (NASA) is worried about their batteries running out -- they may not have enough sunlight to recharge them."
If Phoenix lands on Martian soil next year, the lidar will have a lid to protect it from the dust. That lid will remain firmly shut until the device starts taking measurements, and can easily close tight again if necessary.
"We just batten down the hatches if there's a dust storm and wait it out," said Duck.
There's so much dust on Mars, it's become a crucial element in the planet's weather formations, influencing how hot the surface gets or how much sunlight reaches the ground.
"In Earth's atmosphere, carbon dioxide is very important for climate. But on Mars, it's actually the dust that's the key thing," said Duck. "So the dust is really what determines temperatures in the Martian atmosphere, and so really determines the climate."
But it's the water that scientists are really looking for. Experts believe Mars once had giant oceans and lakes just like Earth, but now all that's left are the polar caps and possibly some faint clouds.
The great unsolved mystery is where the water went, and studying the current water cycle could offer the answer.
"We're landing at about 70 degrees north, so in the northern plains in the high north of Mars. The ice cap there actually expands and contracts with the seasons, and all of that water from the ice cap has to go somewhere, so we figure there are probably fogs that develop, frost, and there appear to be clouds as well," said Duck.
"We're interested in being able to take measurements of these things and to try and understand this water cycle."
On Earth, clouds break apart and cause rain, which then feeds into rivers and lakes. The sun then evaporates the water, starting the whole process over again as water particles drift upwards and form more clouds.
"On Mars, there just isn't enough water available to do that," explained Duck. "You probably form some clouds, but they're not going to be anywhere near as thick as on Earth, and we don't expect to see precipitation the way that we see it here."
Studying how water moves around on Mars could also give a peak into whether life ever existed on the rocky planet -- or if it still does.
Scientists are not discounting the possibility that somewhere on the Red Planet, organisms are still clinging to life, taking advantage of what little water remains.
"All of our indications are that water is a basic building block of life. So actually going there and detecting water is a really big deal," said Duck.
"With the Phoenix mission, one of its goals is to actually go and touch the water. It will be the first instrument to do that. We have a lot of indirect detections of water from orbiting radars and spectrometers and things like that. But the Phoenix, on the other hand, will actually go and dig under the soil and pick up whatever's there and deposit it into a chemical analyzer. One of the things we'll look for is water, and we'll also look for organic matter."
The next opportunity for Phoenix to blast off from Cape Canaveral, Florida is this Saturday at 5:26 a.m. ET.
