US-French satellites map world oceans, rivers and lakes
US-French satellite map world oceans, rivers and lakes
A US-French satellite that will map nearly every ocean, lake and river in the world has been launched into orbit.
The predawn launch Friday aboard a SpaceX rocket from Vandenberg Space Force Base in California capped off a very successful year for NASA.
The satellite, nicknamed SWOT is needed more than ever as climate change exacerbates droughts, floods and coastal erosion, according to scientists. Control centers in California and France erupted in cheers as the spacecraft began its mission.
This is a pivotal moment, and I’m very excited about it, said Nadya Vinogradova-Shiffer, NASA program manager. We are going to see Earth’s water like never before.
The satellite, about the size of an SUV will measure water levels on more than 90 percent of Earth’s surface, allowing scientists to track water flow and identify potentially high-risk areas. It will also survey millions of lakes and 2.1 million kilometers of rivers, from source to mouth.
The satellite will beam radar pulses back toward Earth, which will be picked up by a pair of antennas on either end of a 10-meter boom.
NASA’s current fleet of nearly 30 Earth-observing satellites can not make out such subtle features. While these older satellites can map the extent of lakes and rivers, their measurements are not detailed, says Tamlin Pavelsky of the University of North Carolina.
Perhaps most importantly, the satellite will reveal where and how fast sea levels are rising and changes to coastlines are key to saving lives and property. It will cover the Earth between the North Pole and Antarctica at least every three weeks as it orbits at an altitude of more than 890 kilometers.
Laurie Lessing, director of NASA’s Jet Propulsion Laboratory in Pasadena, California, noted that while the agency is best known for its Mars rovers and space telescopes, this is the planet we care about most.
She added that we have a lot of people looking at Earth, with more global survey missions planned for the next few years.
NASA and the French space agency collaborated on a $1.2 billion SWOT project about 20 years in the making and the UK and Canada also participated.
Already recovered, the first-stage booster returned to Vandenberg eight minutes after liftoff to fly again one day. When the double sonic boom went off, everyone jumped up, it was exhilarating
This is the latest milestone for NASA this year. Other highlights include; amusing pictures of the universe from the new Webb Space Telescope; the Dart spacecraft crashing into an asteroid without error in the first planetary defense test.
NASA’s Mars rover captures first sound of dust storm on Red Planet
NASA can now say what a dust storm on Mars might sound like. As a swirling tower of red dirt passed directly overhead, a NASA rover accidentally switched on its microphones and recorded the racket.
For about 10 seconds, there were not only rumbling gusts of up to 40 km/h, but also the thumping of hundreds of dust particles against the Perseverance rover. Scientists report the first such audio on Tuesday.
We hit the jackpot when the rover’s microphone picked up the noise from the dust storm overhead, lead author Naomi Murdoch of the University of Toulouse told AFP.
According to the researchers, it sounds eerily similar to dust storms on Earth, but is quieter thanks to the thinner atmosphere on Mars that makes the sound softer and less windy.
Dust storms came and went quickly last year, so the length of the audio is short, Murdoch said. Meanwhile, a navigation camera on the parked rover captured images, while its weather-monitoring instruments collected data.
It was completely seize on the spot by Persy, said co-author German Martinez of the Lunar and Planetary Institute in Houston.
Photographed on Mars for decades but never heard of, until now, dust storms are common on the red planet — especially at Jezero Crater, where the Perseverance rover has been since February 2021 run. But it has never successfully recorded their audio before.
On September 27, 2021, a dust storm 118 meters (390 feet) high and 25 meters wide passed directly above the rover at a speed of five meters (16 feet) per second.
Murdoch said the microphone picked up 308 dust pulses as the dust storm passed by.
Given that the rover’s SuperCam microphone is turned on for less than three minutes every few days, Murdoch said it was absolutely luck when the dust storm appeared. She estimated that there was only a 1 in 200 chance of capturing the dust storm audio.
Of the 84 minutes collected in the first year, there was only one dust storm recording, she told The Associated Press in an email from France.
We hear the wind associated with the dust storm, and the moment it arrives, we can’t hear anything because we’re in the eye of the vortex, said Murdoch, a planetary researcher at the ISAE-SUPAERO space research institute in France.
Then, she added, the sound came back as the microphone passed through the second wall of the dust storm.
The tac tac tac sound from the impact of the dust will allow researchers to count the particles to study the structure and behavior of the cyclone, she said.
It could also help solve a mystery that has plagued scientists. In some places on Mars, the cyclones clean the rover’s solar panels along the way by sucking up dust, Murdoch said.
But in other areas, cyclones don’t kick up much dust as they pass by. They’re just moving the air, Murdoch said, adding we don’t know why.
For example, the solar panels on NASA’s InSight lander are dusty because it’s in a location that doesn’t take advantage of these natural vacuums, she said.
Understanding why this happens could help scientists build a model of the dust storm that can predict where the cyclone is likely to hit next.
The same microphone on Perseverance’s mast provided the first sound from Mars, the Martian wind, shortly after the rover landed in February 2021. It then played audio of the rover driving around, and its companion helicopter, the Ingenious, flying nearby as the rover rocked the crackle of its lasers, the microphone’s main cause.
These records allow scientists to study Martian winds, atmospheric turbulence and now dust movement in unprecedented ways, Murdoch said. The results demonstrate the value of acoustic data in space exploration.
Planetary scientist Sylvestre Maurice, a co-author of the study published in the journal Nature Communications, said analyzing Martian dust could probe the surface and the extremely thin atmosphere interaction between.
Billions of years ago the atmosphere was much thicker, allowing life-sustaining liquid water to exist, said Morris, who also works on SuperCam.
You might think that studying Martian climate today has nothing to do with finding traces of life billions of years ago, he said.
But it’s part of a whole, because the history of Mars is a history of extreme climate change, from a humid, hot planet to a completely dry and cold one.
In search of rocks that may contain signs of ancient microbial life, Perseverance has so far collected 18 samples at Jezero Crater, once the site of a river delta. NASA plans to return these samples to Earth in a decade. Ingenuity Helicopters has logged 36 flights, with the longest flight lasting nearly three minutes.