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How dry is Mars? – Skywatching – Castanet.net

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With Mars now the most intensively explored planet in the Solar System after ours, it is not surprising that we are continually having to review our ideas and preconceptions.

The Red Planet continues to challenge our imaginations.

The mainstream idea is that originally Mars had lots of water, but being a smaller world, with weaker gravity, and losing its magnetic field early on, its atmosphere and water got lost to space, leaving a cold, dry desert world.

Now, it looks as though we could be seriously wrong in our assumption that Mars is now a dried-up world.

Current estimates are that around three billion years ago, when life was first getting started in the Earth’s oceans and possibly on Mars too, there was enough water on Mars to submerge the whole planet to a depth of between 100 and 1000 metres.

By comparison, if our Earth were a smooth ball, the existing oceans would cover it to a depth of well over 2000 metres. Mars once had a lot of water; by about a billion years ago, it had disappeared.

There are three places the Martian oceans could have disappeared to.

  • One is, as we know, the loss of water to space.
  • A second is the presence of lots of ice hidden underground, and possibly underground or under-ice briny lakes.
  • A third option is that water got taken up and combined with various minerals. This water is chemically tied up and can remain sequestered for a long time.

At some point in our high-school science career most of us have heated copper sulphate.

As we warmed it, those nice blue crystals turned into white powder and water came off as steam. Before we applied the heat the crystals were perfectly dry.

The water molecules were locked up inside the crystals as part of the chemical. There are many minerals that similarly lock up water.

The first rocks on Mars would have been volcanic. However, Mars, like Earth, was then a wet world, with rain and other weather.

On Earth, rocks are continually attacked and broken down, a process we call weathering. The situation on Mars would have been the same. In the process, minerals in the rock become new minerals that contain water, such as clays.

From observations done from orbit and on the Martian surface, it looks as though there is a lot of water tied up in hydrated minerals.

Apart from our interest in this information in helping us understand the history of the planet in the Solar System most like ours, it also is important regarding our plans to have long-term manned bases, or even colonies on Mars.

The red surface of Mars indicates iron oxides, which contain oxygen. In addition, we can use solar-generated electricity to liberate oxygen from water.

Given that current space technology means Mars is always many months away, the more self-sufficient our bases are for the key needs of energy, water and oxygen, the less dependent they will be upon Earthly support, and the more secure they will be in the long term.

Moreover, the more water there is, the better the long-term prospects of terraforming the planet.

Before messing with the Martian environment, we need to know whether there are living things on the planet. The last thing we would want to do is render their world uninhabitable to them.

The presence of water tied up in minerals rather than just frozen solid offers easier prospects for Martians to make a living, because water is an important component in extracting useful chemicals from their surroundings, maybe, as is the case on Earth, with the help of the Sun.

It is true that the solar ultraviolet radiation level on the surface of Mars is dangerous to us, but that radiation has a lot of energy in it, and there is no reason Martians, if any, will be like us.

  • Mars is high in the southwest after dark.
  • Jupiter and Saturn lie low in the southeast just before dawn.
  • The Moon will be New on the 11th.

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Oldest human footprints in North America found in New Mexico – CTV News

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WASHINGTON —
Fossilized footprints discovered in New Mexico indicate that early humans were walking across North America around 23,000 years ago, researchers reported Thursday.

The first footprints were found in a dry lake bed in White Sands National Park in 2009. Scientists at the U.S. Geological Survey recently analyzed seeds stuck in the footprints to determine their approximate age, ranging from around 22,800 and 21,130 years ago.

The findings may shed light on a mystery that has long intrigued scientists: When did people first arrive in the Americas, after dispersing from Africa and Asia?

Most scientists believe ancient migration came by way of a now-submerged land bridge that connected Asia to Alaska. Based on various evidence — including stone tools, fossil bones and genetic analysis — other researchers have offered a range of possible dates for human arrival in the Americas, from 13,000 to 26,000 years ago or more.

The current study provides a more solid baseline for when humans definitely were in North America, although they could have arrived even earlier, the authors say. Fossil footprints are more indisputable and direct evidence than “cultural artifacts, modified bones, or other more conventional fossils,” they wrote in the journal Science, which published the study Thursday.

“What we present here is evidence of a firm time and location,” they said.

Based on the size of the footprints, researchers believe that at least some were made by children and teenagers who lived during the last ice age.

David Bustos, the park’s resource program manager, spotted the first footprints in ancient wetlands in 2009. He and others found more in the park over the years.

“We knew they were old, but we had no way to date the prints before we discovered some with (seeds) on top,” he said Thursday.

Made of fine silt and clay, the footprints are fragile, so the researchers had to work quickly to gather samples, Bustos said.

“The only way we can save them is to record them — to take a lot of photos and make 3D models,” he said.

Earlier excavations in White Sands National Park have uncovered fossilized tracks left by a saber-toothed cat, dire wolf, Columbian mammoth and other ice age animals.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

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Inspiration4 Lift Off: SpaceX Launches World’s First All-Citizen Mission in Earth’s Orbit – Illinoisnewstoday.com

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Tampa, Florida (WFLA) — SpaceX made history on Wednesday night when it launched the world’s first all-civil mission to get going from the Space Coast, Florida.

The Inspiration4 mission took off from Launch Complex 39A at NASA’s Kennedy Space Center around 8:03 pm on Wednesday. The four crew members on the SpaceX Dragon spacecraft were launched onto a reusable Falcon 9 rocket and later separated from the spacecraft and landed on the drone.

The mission’s five-hour launch window began at 8:02 EST. The window was very large, as the crew was sent to orbit the Earth rather than the International Space Station, and therefore did not have such strict time constraints.

The crew is set to travel 350 miles above the surface of the Earth, about 100 miles higher than the International Space Station.

“This is important and historic, because it’s the best time humans have been in orbit since the Hubble Space Telescope mission,” said Benjireed, SpaceX’s manned spaceflight director.

(Photo provided by SpaceX)

The crew will spend three days in orbit to participate in research experiments on human health and performance. We hope that the results of our research will apply not only to future space flight, but also to human health here on Earth.

Inspiration4’s main goal is to provide and inspire support for St. Jude Children’s Research Hospital. They want to raise $ 200 million for St. Jude in a three-day mission.

According to SpaceX, each of the four members of the crew was chosen to represent the pillars of a mission of prosperity, generosity, hope and leadership. The Inspiration 4 crew and the pillars they represent are:

  • leadership: 38 years old Jared Isaacman – Founder and CEO of Shift4Payments
  • Hope: 29-year-old Haley Arseno – Doctor assistants and childhood cancer survivors treated with St. Jude
  • Generosity: 41 years old Chris Sembroski – Lockheed Martin US Air Force veteran and aerospace employee
  • prosperity: 51 years old Dr. Cyan Proctor – Entrepreneurs, educators, trained pilots, and the active voice of the space exploration community

SpaceX trained all four crew members as commercial astronauts on Falcon 9 and Dragon spacecraft. The crew was trained in orbital mechanics, microgravity, weightlessness, other stress tests, emergency preparedness, and spacesuit training.

The mission was funded by Isaacman in a private transaction with SpaceX. Isaacman has also invested $ 100 million towards a funding target for the St. Jude mission.

Inspiration4 Lift Off: SpaceX Launches World’s First All-Citizen Mission in Earth’s Orbit

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'Flying' microchips could ride the wind to track air pollution – Yahoo Movies Canada

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Researchers have created a winged microchip around the size of a sand grain that may be the smallest flying device yet made, Vice has reported. They’re designed to be carried around by the wind and could be used in numerous applications including disease and air pollution tracking, according to a paper published by Nature. At the same time, they could be made from biodegradable materials to prevent environmental contamination. 

The design of the flyers was inspired by spinning seeds from cottonwood and other trees. Those fall slowly by spinning like helicopters so they can be picked up by the wind and spread a long distance from the tree, increasing the range of the species. 

The team from Northwest University ran with that idea but made it better, and smaller. “We think we’ve beaten biology… we’ve been able to build structures that fall in a more stable trajectory at slower terminal velocities than equivalent seeds,” said lead Professor John A. Rogers. “The other thing… was that we were able to make these helicopter flyer structures that are much smaller than seeds you would see in the natural world.”  

They’re not so small that the aerodynamics starts to break down, though. “All of the advantages of the helicopter design begin to disappear below a certain length scale, so we pushed it all the way, as far as you can go or as physics would allow,” Rogers told Vice. “Below that size scale, everything looks and falls like a sphere.”

The devices are also large enough to carry electronics, sensors and power sources. The team tested multiple versions that could carry payloads like antenna so that they could wireless communicate with a smartphone or each other. Other sensors could monitor things like air acidity, water quality and solar radiation. 

The flyers are still concepts right now and not ready to deploy into the atmosphere, but the team plans to expand their findings with different designs. Key to that is the use of biodegradable materials so they wouldn’t persist in the environment. 

“We don’t think about these devices… as a permanent monitoring componentry but rather temporary ones that are addressing a particular need that’s of finite time duration,” Rogers said. “That’s the way that we’re envisioning things currently: you monitor for a month and then the devices die out, dissolve, and disappear, and maybe you have to redeploy them.”

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