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Nasa finds evidence of a vast ancient ocean on Mars

A massive ancient ocean once covered nearly half of the northern hemisphere of Mars making the planet a more promising place for alien life to have gained a foothold, Nasa scientists say.

The huge body of water spread over a fifth of the planet’s surface, as great a portion as the Atlantic covers the Earth, and was a mile deep in places. In total, the ocean held 20 million cubic kilometres of water, or more than is found in the Arctic Ocean, the researchers found.

Unveiled by Nasa on Thursday, the compelling evidence for the primitive ocean adds to an emerging picture of Mars as a warm and wet world in its youth, which trickled with streams, winding river deltas, and long-standing lakes, soon after it formed 4.5bn years ago.

The view of the planet’s ancient history radically re-writes what many scientists believed only a decade ago. Back then, flowing water was widely considered to have been a more erratic presence on Mars, gushing forth only rarely, and never forming long-standing seas and oceans.

“A major question has been how much water did Mars actually have when it was young and how did it lose that water?” said Michael Mumma, a senior scientist at Nasa Goddard Space Flight Center in Maryland.

Writing in the journal, Science, the Nasa team, and others at the European Southern Observatory (ESO) in Munich, provide an answer after studying Mars with three of the most powerful infra-red telescopes in the world.

The scientists used the Keck II telescope and Nasa’s Infrared Telescope Facility, both in Hawaii, and the ESO’s Very Large Telescope in Chile, to make maps of the Martian atmosphere over six years. They looked specifically at how different forms of water molecules in the Martian air varied from place to place over the changing seasons.

Martian water, like that on Earth, contains standard water molecules, made from two hydrogen atoms and one oxygen atom, and another form of water made with a heavy isotope of hydrogen called deuterium. On Mars, water containing normal hydrogen is lost to space over time, but the heavier form is left behind.

When normal water is lost on Mars, the concentration of deuterium in water left behind goes up. The process can be used to infer how much water there used to be on the planet. The higher the concentration of deuterium, the more water has been lost.

The infrared maps show that water near the Martian ice caps is enriched with deuterium. The high concentration means that Mars must have lost a vast amount of water in the past, equivalent to more than six times that now locked up in the planet’s frozen ice caps.

The scientists calculate that the amount of water was enough to create a global ocean that covered the entire surface of Mars to a depth of 137m. But Mars was probably never completely submerged. Based on the Martian terrain today, the scientists believe the water pooled into a much deeper ocean in the low-lying northern plains, creating an ocean that covered nearly a fifth of the planet’s surface. The Atlantic, by comparison, covers about 17% of Earth’s surface.

“Ultimately we can conclude this idea of an ocean covering 20% of the planet which opens the idea of habitability and the evolution of life on the planet,” said Geronimo Villanueva, the first author on the study.

The huge body of water lasted for millions of years. But over time, the Martian atmosphere thinned. The drop in pressure meant more ocean water wafted into space. The planet lost much of its insulation too. No longer warm enough to keep the water liquid, the ocean receded and eventually froze. Today, only 13% of the ocean remains, locked up the Martian polar caps.

“We now know Mars was wet for a much longer time than we thought before,” said Mumma. Nasa’s Curiosity rover has already shown that Mars had standing water for 1.5 billion years, longer than it took for life to emerge on Earth. “Now we see that Mars must have been wet for a period even longer,” Mumma added.

John Bridges, a planetary scientist at Leicester University, who works on Nasa’s Curiosity rover mission, said Mars was surely at least habitable in the distant past. “Ten years ago, the story of water on Mars was an occasional flood of rocky debris every 100m years that then switched off again. We now know it’s more continuous. There were long-standing bodies of water: lakes, deltas and perhaps even seas,” he said.

“It seems to me that we have excellent evidence that Mars was once habitable, though whether it was ever inhabited is not clear. But there’s a chance. A life-bearing meteorite might have been ejected from Earth and could have landed in the water on Mars,” he added.

The search for life on Mars will ramp up in 2018 when the European Space Agency sends its Exomars rover to the red planet. The rover will look for chemical signatures of life, perhaps emanating from microbes living deep beneath the Martian soil. Last year, Nasa’s Curiosity rover detected methane in the Martian atmosphere. The finding sparked intense speculation that the gas might be coming from living organisms. It might, but there is no evidence to suggest it is. Methane is regularly produced on planets through geological processes without any need for life.

Charles Cockell, professor of astrobiology at Edinburgh University, said: “The longer water persists on a planetary body in one location, particularly if there is geological turnover, the more likely it is that it would provide a habitable environment for a suitable duration for life to either originate or proliferate. An ocean would meet this need.” That life was possible does not make it inevitable though. “Of course, it could have been uninhabited,” he added.

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Voyager 2 has discovered something amazing: Denser space outside the solar system

In November 2018, after a 41-year voyage, Voyager 2 crossed the boundary beyond which the Sun’s influence ends, and entered interstellar space. But the mission of the little probe is not yet complete – it continues to make amazing discoveries

Perhaps the probes have found some kind of traffic jam at the edge of the solar system. The Voyager flight continues and we will soon find out what it was.

Voyager 2 discovered something amazing: as the distance from the Sun increases, the density of space increases.

Voyager 1, which entered interstellar space in 2012, transmitted similar indicators to Earth. New data have shown that the increase in density may be a feature of the interstellar medium.

The solar system has several boundaries, one of which, called the heliopause, is determined by the solar wind, or rather by its significant weakening. The space inside the heliopause is the heliosphere, and the space outside is the interstellar medium. But the heliosphere is not round. It looks more like an oval, in which the solar system is at the leading edge, and a kind of tail stretches behind it.

Both Voyagers crossed the heliopause at the leading edge, but within 67 degrees heliographic latitude and 43 degrees longitude apart.

Interstellar space is usually considered a vacuum, but this is not entirely true. The density of matter is extremely small, but it still exists. In the solar system, the solar wind has an average density of protons and electrons from 3 to 10 particles per cubic centimeter, but it is lower the further from the Sun.

The average concentration of electrons in the interstellar space of the Milky Way is estimated to be about 0.037 particles per cubic centimeter. And the plasma density in the outer heliosphere reaches approximately 0.002 electrons per cubic centimeter. When the Voyager probes crossed the heliopause, their instruments recorded the electron density of the plasma through plasma oscillations.

Voyager 1 crossed the heliopause on August 25, 2012 at a distance of 121.6 astronomical units from the Earth (121.6 times the distance from Earth to the Sun – about 18.1 billion km). When he first measured plasma oscillations after crossing the heliopause on October 23, 2013 at a distance of 122.6 astronomical units (18.3 billion km), he found a plasma density of 0.055 electrons per cubic centimeter.

After flying another 20 astronomical units (2.9 billion kilometers), Voyager 1 reported an increase in the density of interstellar space to 0.13 electrons per cubic centimeter.

Voyager 2 crossed the heliopause on November 5, 2018 at a distance of 119 astronomical units (17.8 billion kilometers. On January 30, 2019, it measured plasma oscillations at a distance of 119.7 astronomical units (17.9 billion kilometers), finding that the density plasma is 0.039 electrons per cubic centimeter.

In June 2019, Voyager 2’s Instruments showed a sharp increase in density to about 0.12 electrons per cubic centimeter at a distance of 124.2 astronomical units (18.5 billion kilometers).

What caused the increase in the density of space? One theory is that the lines of force of the interstellar magnetic field become stronger with distance from the heliopause. This can cause electromagnetic ion cyclotron instability. Voyager 2 did detect an increase in the magnetic field after crossing the heliopause.

Another theory is that the material carried away by the interstellar wind should slow down in the heliopause, forming a kind of plug, as evidenced by the weak ultraviolet glow detected by the New Horizons probe in 2018, caused by the accumulation of neutral hydrogen in the heliopause.

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NASA has banned fighting and littering on the moon

New details of the agreement signed by representatives of a number of countries on the development of the moon and the extraction of minerals within the framework of the Artemis program have appeared. Reported by the National Aeronautics and Space Administration (NASA).

So, astronauts involved in the mission are prohibited from littering and fighting on the territory of a natural satellite of the Earth.

So, we present to you the new rules for being on the Moon:

Everyone comes in peace;

Confidentiality is prohibited, all launched objects must be identified and registered;

All travel participants agree to help each other in case of emergencies;

All received data is transferred to the rest of the participants, and space systems must be universal;

Historic sites must be preserved and all rubbish must be disposed of;

Rovers and spacecraft should not interfere with other participants.

“”It is important not only to go to the moon with our astronauts, but also that we bring our values ​​with us,” said Mike Gold, acting head of NASA’s international and inter-agency relations.

According to him, violators of the above rules will be asked to “just leave” the territory of the moon.

The effect of these principles so far applies to eight signatory countries of the agreement: the USA, Australia, Canada, Italy, Japan, Luxembourg, the United Arab Emirates and the United Kingdom. Countries other than China can join if they wish.

 It should be noted that at the moment NASA is prohibited from signing any bilateral agreements with the PRC leadership.

The first NASA mission to the moon, known as “Artemis 1”, is scheduled for 2021 without astronauts, and “Artemis 2” will fly with a crew in 2023.

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Methane snow found on the tops of Pluto’s equatorial mountains

Scientists believe that it arose as a result of the accumulation of large amounts of methane at an altitude of several kilometers above the surface of the planet.

In the images of the Cthulhu region – a dark region in the equatorial regions of Pluto – planetary scientists have found large reserves of methane snow that covers the peaks of local mountains and hills. It formed quite differently from how snow forms on Earth, astronomers write in the scientific journal Nature Communications.

“The white caps on the tops of Pluto’s mountains did not arise from the cooling of air currents that rise along the slopes into the upper atmosphere, as it happens on Earth, but from the accumulation of large amounts of methane at an altitude of several kilometers above Pluto’s surface. This gas condensed on the mountain tops, “the scientists write.

We owe almost everything we know about Pluto to the New Horizons interplanetary station. It was launched in January 2006, and in mid-July 2015 the station reached the Pluto system. New Horizons flew just 13 thousand km from the dwarf planet, taking many photographs of its surface. 

New Horizons data indicated an interesting feature of Pluto – in its depths, a giant subglacial ocean of liquid water can be hidden. It can be a kind of engine of those geological processes, traces of which can be seen on the surface of a dwarf planet. Because of this discovery of New Horizons, many discussions began among planetary scientists. Scientists are trying to understand how such a structure could have arisen, as well as to find out the appearance of Pluto in the distant past.

Members of the New Horizons science team and their colleagues from France, led by planetary scientist from NASA’s Ames Research Center (USA) Tanguy Bertrand, have discovered another unusual feature of Pluto. They studied the relief of one of the regions of the dwarf planet – the Cthulhu region. This is what astronomers call a large dark region at Pluto’s equator, which is whale-like in shape and is covered in many craters, mountains and hills.

Snow in Pluto’s mountains

By analyzing images of these structures taken by the LORRI camera installed on board New Horizons, astronomers have noticed many blank spots on the slopes of the highest mountain peaks. Having studied their composition, scientists have found that they consist mainly of methane.

Initially, planetary scientists assumed that these are deposits of methane ice. However, Bertrand and his colleagues found that the slopes and even the tops of Pluto’s equatorial mountains are actually covered not only with ice, but also with exotic methane snow that forms right on their surface.

Planetary scientists came to this conclusion by calculating how methane behaves in Pluto’s atmosphere. In doing so, they took into account how the molecules of its gases interact with the sun’s rays and other heat sources. It turned out that at the equator of Pluto, at an altitude of 2-3 km from its surface, due to the special nature of the movement of winds, unique conditions have formed, due to which snow is formed from methane vapor.

Unlike Earth, where such deposits are formed as a result of the rise of warm air into the upper atmosphere, on Pluto this process goes in the opposite direction – as a result of contact of the cold surface of the peaks and slopes of mountains with warm air masses from the relatively high layers of the dwarf planet’s atmosphere.

Previously, as noted by Bertrand and his colleagues, scientists did not suspect that this was possible. The fact is that they did not take into account that due to the deposition of even a small amount of methane snow and ice, the reflectivity of the peaks and slopes of mountains in the Cthulhu region increases. As a result, their surface temperature drops sharply, and snow forms even faster.

Scientists suggest that another mysterious feature of Pluto’s relief could have arisen in a similar way – the so-called Tartarus Ridges, located east of the Sputnik plain. A distinctive feature of this mountainous region is strange peaks that are shaped like skyscrapers or blades. Bertrand and his colleagues suggest that these peaks are also methane ice deposits that grow “from top to bottom.”

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