#which of course had a lot of past and to some degree present volcanic activity

[rohirric-hunter]

Hey so why's there a cave full of columnar jointing in Outer Gondor. What's the implication here

[sciencespies]

Scientists say they've identified the best place for life to have existed on Mars

https://sciencespies.com/space/scientists-say-theyve-identified-the-best-place-for-life-to-have-existed-on-mars/

Scientists say they've identified the best place for life to have existed on Mars

The surface of Mars, by every measurement we’ve taken, is currently an inhospitable wasteland. Only dust devils roam its arid surface; the only water is permanent ice. Yet evidence that water once flowed and pooled on the planet’s surface keeps mounting.

The presence of this liquid water means that Mars could have supported life as we know it… but one burning question remains: how in the heck was Mars warm enough for it, in the early days of the Solar System, when the young Sun was cooler and fainter?

New research has found an answer: geothermal heat could have risen from deep inside the planet – in which case, the best place for life to thrive would have been deep underground.

“Even if greenhouse gases like carbon dioxide and water vapor are pumped into the early Martian atmosphere in computer simulations, climate models still struggle to support a long-term warm and wet Mars,” said planetary scientist Lujendra Ojha of Rutgers University-New Brunswick.

“I and my co-authors propose that the faint young Sun paradox may be reconciled, at least partly, if Mars had high geothermal heat in its past.”

The faint young Sun paradox is the contradiction between the presence of liquid water in the early Solar System, and the faintness of the Sun. According to our understanding of stellar evolution, in the billion or so years after its formation 4.6 billion years ago, the Sun’s heat and light would only have been about 70 percent of its current output.

Even today, Mars is a chilly place. It’s 1.5 times Earth’s distance from the Sun, and it only receives about 43 percent of the solar flux Earth does. Its average temperature is therefore much lower than Earth’s – -63 degrees Celsius (-81 degrees Fahrenheit). Of course, that’s just the average; the temperature does rise above the melting point of water, to about 30 degrees Celsius (although, because the atmospheric pressure on Mars is currently so low, ice sublimates rather than melting).

During the Noachian period on Mars, between around 4.1 and 3.7 billion years ago, water is thought to have been abundant on the planet’s surface – yet climate models struggle to reach temperatures above -0.15 degrees Celsius.

The possibility that the planet heated itself from within, maintaining liquid groundwater long-term, is not a new notion. Hydrothermal minerals excavated from deep underground from cometary impacts, Noachian era-clays and evidence of groundwater diagenesis at a number of sites support internal heating models.

Here on Earth, we see the effects of geothermal heating beneath the ice sheets at high latitudes. The radioactive decay of elements such as uranium, potassium and thorium in the planet’s crust generates heat that propagates through to the surface; not much, but when there’s a thick sheet of ice preventing that heat from escaping, enough heat can be trapped to melt some of that ice, creating subglacial lakes.

So, Ojha and his team investigated the possibility that this could have occurred on Mars during the Noachian. They modelled the thermophysical evolution of ice, and estimated how much heat would be required to produce meltwater and subglacial lakes on a cold and frozen Mars.

Then, they compared this to various Mars datasets to determine whether this would have been feasible on Mars 4 billion years ago. And they found that the conditions to melt subsurface water would have been ubiquitous at the time, with volcanism and meteorite impacts possibly providing additional heat.

It’s still possible that Mars’ surface was warm and wet for a time, but that climate would not, the researchers said, have been stable long-term. Mars lost its magnetic field pretty early on in its history – sometime around the Noachian – and once the magnetic field was gone, the thick, Earth-like atmosphere wouldn’t have lasted much longer.

Only at great depths, kept liquid by geothermal heating, could water have been stable long-term, the researcher said. If there was life at the surface, it could have followed the water inwards.

“At such depths, life could have been sustained by hydrothermal (heating) activity and rock-water reactions,” Ojha said. “So, the subsurface may represent the longest-lived habitable environment on Mars.”

Other research using sonar suggests that liquid water is still present underground on Mars today, although the reason it doesn’t melt could be quite different. Scientists believe that underground Mars lakes could be extremely salty, since salinity lowers the freezing point of water.

And scientists have found evidence of mud volcanism on Mars, where subsurface wet sediments are pushed up and out from pressure underground. The water, of course, would sublimate once it reached the surface. But each piece of evidence is pointing to a very different sort of Mars once you crack the crust.

Three new missions to Mars launched in July of this year, due to arrive in February 2021. Perhaps we’re very close to getting a lot more answers.

The research has been published in Science Advances.

#Space

[justforustravel-blog]

Spectacular Natural Wonders In Our World - #AmazonRainForest, #AngelFalls, #Argentina, #Arizona, #Aurora, #Australia, #BigReef, #Bolivia, #CanadaMoraineLake, #Cappadocia, #China, #Discovery, #GrandCanyon, #HaLongBay, #HimalayaMountain, #LauterbrunnenValley, #Maldives, #Mexico, #MountRoraima, #Norway, #Patagonia, #Philippin, #Sahara, #Switzerland, #TheCrystalCave, #TheFirstDiscovery, #TheLakeSalarDeUyuni, #TheMoneyCanyon, #ThePulpitRock, #TheStoneForest, #Tourism, #Usa, #Venezuela, #Vietnam, #VulcanIsland

New Post has been published on http://justforustravel.com/2017/10/05/spectacular-natural-wonders-in-our-world/

Spectacular Natural Wonders In Our World

political interests and conflicts are left behind when the boundaries disappear and our earth is how beautiful you are to understand what we are actually first. When you’re a citizen of the world, it’s a matter of time to realize that the world is a beautiful place. When we saw it for a minute you can prepare your bag and take on the road without thinking. Here’s our have listed for you the natural wonders of this spectacular earth. Hopefully we will all be able to at least get a chance to see most of them.

  Patagonia, Argentina

the amazing nature of Patagonia, one of the world’s largest glaciers. The first discovery, or more precisely the western world has made to promote the famous Explorer Magellan. Argentina’s is located in South. Generally this region is dominated by a cold climate. There are also geographic shapes and steep high mountains with unique views. The struggle for survival, the documentary hosts a lot of competition.

  Grand Canyon, USA

Grand Canyon, USA’s one of the oldest and largest canyons. Sun n according to the state of the cliffs of the canyon creates a nice looking place and undergoes the color change. Over millions of years the Colorado River has become today due to the canyon shape. This is also easily available with many fossils from millions of years in the canyon, about the past sheds light on the present. And even contributed to the growth of a new generation of scientists.

  Aurora

generally seen between 60 to 72 degrees north and South latitudes. A lot of call for it has been shown by the locals in the fields. Ancient times and has become a source of faith. Of course, today such a situation it is very unlikely. While the sun’s rays reaching the earth is a condition that occurs as a result of the changes they have suffered. The northern lights, the aurora borealis, the Aurora Australis lights of the South is called. I think especially a place where cold lovers want to see.

  Maldives

The Maldive islands consists of 1200 islands. There are approximately 281 living in this. In the majority maldivli lives, or some of the islands belonging to Parties with the hotel’s name as it is used. I personally as someone who doesn’t like hot you wouldn’t want to live here. I watched in a documentary as I can tell, the ones who enjoy this island community, only rich people who come at certain times. They didn’t seem too happy with the situation of the islanders. The general economy of the islands, fishing and, of course, on tourism.

  Amazon rain forest

First, if it is necessary to define the rain forest the rain forest is called the forest of 1750-2000 mm rainfall annual amounts. Are found in the tropical regions. The Amazon forest is one of the most beautiful examples of. 9 the forests of the Amazon is located within the border of the country. Sayid is home to various types of animals and plants is very high. And as the days passed, new species still exists. According to scientists, the Amazon is kind of thousands still waiting to be discovered. In this respect a very important place. Another important issue are a tribe without any connection with the world. Mankind’s most primitive tribes, still in the depths of the Amazon, these totally disengaged from the outside world and they live in their form. International institutions were taken under protection. Hopefully life can continue as they have.

Vulcan Island, Philippines

trying to write something about this name makes me laugh, I can’t keep myself. or to describe the location of the island because the island pushes the limits of human grammar and whether or not I felt I had to include this island in this list. Island, Philippines is situated. To me, the state of being so different and unique. Because Vulcan full definition of the island: in the island of Luzon Taal main crater lake, the volcanic island in the island in the lake. Here’s very difficult to tell the location of the island. Around the volcano there are plenty of geological movement exactly as expected and there is plenty of a continent is located at the point of collision.

  Sahara

well, the largest desert in the world. You can fit it almost one in the United States.Full 11 is included within the borders of the country. How it is that we can understand. Thousands of years ago, the Sahara rivers, there were forests. World’s the shift of the axis, since with the increase of temperature today reached into. And as you can imagine, the first thing that comes to our mind when we think of the desert, there are plenty of sand dunes here. It is a very hot place, near the sea, there are spots in more temperate areas. Personally I will not hazzetmey much. They will say to you this is Antarctica, Antarctica running’s either I would go.

  Angel falls, Venezuela

Venezuela’Angel falls in the world’s has the distinction of being the tallest waterfall. According to his measurement of the team National Geographic, has a height of 979 m. Almost 1 kilometer. Angel falls prior to 20. yy’s also have been discovered. The western world, but the recognition of the US’has been thanks to a pilot li. Seek out precious stones that saw the waterfall itself, and the world’s Reported here has the rest. Personally, the noise from where water falls from above without encountering any obstacle because I can’t imagine water falls 807 m along.

  Cappadocia

our country and internationally well-known natural wonder, the land of beautiful horses Cappadocia. A place which attracts tourists especially from Asian. Of Cappadocia, both natural and from a historical perspective is of great importance. The first Christian churches located in this region. Also wind, rain tuff chimneys formed by shaping factors such as their volcano is also located here. Has a very big importance for our country. Tourism also contributes to tourism balloon very effectively here. Area very suitable for Camping and caravan accommodation, there are also hostels.

The Stone forest, China

how like a tree from the trees of this forest occurs on the cliffs in whether or not you really. Stone forest, China’s is located in the Greek region of Shilin Yi province. Kunming, the capital’e 90 kilometers. According to geologists, the stone forest, a typical karst features, the face that hosts it. Paleozoic era, this area in the period it was a sea of carbon completely. The movement of the lithosphere has led to the withdrawal of water, and rocks have allowed it to get to that State.Forest reached its present form by exposure to external factors and constantly.

  the Pulpit Rock, Norway.

Norway’s nature indeed. In the country the area is very mountainous, a little warmer in the south side to the north grades are dropping steadily, and that reveals spectacular views of the snow. This is the Pulpit Rock( Preikestolen) is called. Imagine camping there, enjoy the view and water to pull a sleeping bag you sleep. Who knows, no stars, bright nights. This Southern Norway’te, Fjord a place in the High School of rock to a height of 600 m, look down, really required a lot of courage.

the lake salar de uyuni, Bolivia

Here’s one of the largest salt lakes and Bolivia’s southwest. Salt production, as well as in terms of tourism is a very important place. There are trains for nearly 100 years. Also found time during the war in a garrison here for a while. They built the hotel out of salt here people. That is covered with the cactus in it has a name and this name is a name. A 3000 year old mummy in a cave nearby.

  the crystal cave, Mexico

This is a very strange place for the first time, National Geographic’I heard watching a documentary about a documentary I watched and its immediate aftermath. It’s really a fascinating place and by coincidence, to find a place for the miners. But there can’t focus for more than 100 minutes. Extreme heat and extremely high humidity inside the tolerance of the human body is a thing of this. The temperature at 58 degrees and the humidity about 90%. This is Mexico’s also Chihuahua’s also a place in the area of naica mine 300 feet under was found. From this gypsum crystal shapes were understood to be mostly transparent. Approximately 500,000-year time slice, groundwater, temperature, and earth movements emerged as a result of this type of structures.

  the money Canyon, Arizona

if the landforms here are a painter, like something out of the hands of a sculptor. People really are amazed. The money Canyon, southern Utah’s and also Arizona’. Bryce National Park is within the boundaries of. Of the Colorado River is one of the places that shaped. What powerful rivers, the Colorado River Water. A fluctuation sandstone and has literally shaped and made with the most activity here, nature hikes, and of course the canyon transitions. Who would not want to walk in there.

  Big Reef, Australia

The Great Reef, the world’s largest coral reef ecosystem. Is a set of created by living organisms, and is greater at levels that can be detected from space. Northeastern Australia’, queEngland close the holes, in fact the Coral Sea. Was discovered in 1770 by British sailors, and a malfunction in the ship the sailors continued their journey and stay here a while. Taking as the last name of the person who discovered their place in time, Cooktown is named. Very high is a place where various types of creatures live together, but unfortunately human beings for drying where anything touches, this over-fishing and are threatened because of global warming.

  Ha Long Bay, Vietnam

Ha Long Bay is really a spectacle of a view from a high place. In the village there are many islands large and small. Verdant islets and clean water gives a refreshing look. Then you can capture some very good shots with the boat tours. The limestone islands are generally karstic features. Around 2000 is the name of various sizes. Of the islands about 20 million years in a period of intense owing to the rainy climate and external factors, it is believed that it came to this. There are 14 endemic plant species and 60 endemic animal species in Ha Long Bay.

  mount roraima, Venezuela

mount roraima Venezuela’. Highest point is Maverick rock, 2810 meters. What makes him special 400 feet high rock walls. Attracts rock climbers from around the world. Westerners, before it reaches the region from a spiritual perspective is an important place for the Indians. Piratebay is rented from the nearby village and a long walk on the mountain with a guide and Camping is possible at the summit can be accessed if desired. Is sure to be a completely different experience.

  Canada Moraine Lake

Canada’s North America’s all the natural beauty can be easily seen. Especially where indeed mountainous and is dominated by the Arctic climate. That houses are really appealing the fact that nature has all kinds of wild animals. Moraine Lake, Canada’s is within the boundaries of Banff National Park of Alberta in the city. In general, a glacier fed Lake. If I may say so hear the sound of water from the glacier at least once in your life. This Black Sea’I’ve been. People really are fascinated by the sound of the water rocks your multiplier. The water creates such a beautiful lake in this genre.

Lauterbrunnen Valley, Switzerland

Lauterbrunnen Valley, Switzerland, Bern’s a settlement is actually. Of course, from where he takes the name of the valley. And the date is a very old settlement. MS 1304’, as in the Roman Empire was called Lauterbrunnen. This magnificent mountain villages. By 2013, only 2439 there are people living here. The climate is generally cold and rainy days there are lots of snow, and ultimately a high mountainous area.

  Himalaya mountain range

The Temple of mountaineers and mountaineering in the Himalayas. People risk death trying to reach the summit and the Himalayas. The highest peak is the Mount Everest with 8848 m. Full 14 that has 8000 feet high mountain area. Himalaya’s The reason the continent is so high at this point of collision and the movement of the Himalayan mountain range over millions of years to create.This point is still years from 5 to 10 mm increases. Eurasian and Indo – Australian plates collide and the area is a very high pressure is applied. The Himalayas, the world’s terms as the roof has a very important place in mountaineering. Messenger Reinhold’s 14×8000 hazelnut Bronze from Turkey initiated the project of 2% of6#8217;s including a process has started. Climbers have been giving years to complete this project. And there are very few people who have achieved this. Hopefully, also the bronze Nut is one of them. Everest base camp trekking tours are also organized.

[pcmobilezone]

40 Years of Voyager: A Q&A With Dr. Ed Stone at NASA JPL

On August 20, 1977, at Cape Canaveral, Dr. Edward C. Stone, in his role as chief scientist on the NASA Voyager mission, carried out final checks on Voyager 2 before the Titan-Centaur rocket blast it into space. Days later, on Sept. 5, Voyager 1 joined its twin spacecraft and headed out into the dark beyond.

Almost 40 years later, after its flyby of Jupiter and Saturn, Voyager 1 is now in interstellar space, 20.6 billion kilometers, or 137 Astronomical Units (AU), from Earth. Some 17 billion kilometers from Earth, Voyager 2 took a slightly different route, going past Uranus and Neptune, and is currently in the heliosheath, the outermost layer of the heliosphere where solar wind is slowed by the pressure of interstellar gas. Simply put, both spacecraft have traveled further than any spacecraft has boldly gone before.

Remarkably, Dr. Stone is still in his role as chief scientist, despite having just celebrated his 81st birthday. He has been principal investigator on nine NASA spacecraft missions, co-investigator on five other NASA missions, director of NASA's Jet Propulsion Laboratory (JPL) itself from 1991 to 2001, and received many honors, including the NASA Distinguished Service Medal and National Medal of Science. He's also a full-time professor at the California Institute of Technology (Caltech), which manages JPL for NASA.

After a brief stop at NASA JPL Mission Control, where all signals from missions are monitored 24/7 by the Deep Space Network—a geek's thrill indeed—PCMag met up with Dr. Stone, who talked us through a full-size replica of Voyager 1.

Before sitting down to talk, he pointed out the instruments onboard, which include a Magnetic field instrument, Low energy charged particle instrument, Cosmic ray instrument, Plasma instrument, and Plasma wave instrument (Voyager 1 also has an Ultraviolet spectrometer subsystem). They directly support the five scientific investigation teams participating in the Interstellar Mission: Magnetic field investigation, Low energy charged particle investigation, Plasma Investigation (Voyager 2 only), Plasma wave investigation, and Cosmic ray investigation.

Can you take us back and describe the atmosphere at Cape Canaveral on August 20, 1977? It was a very intense period. Thousands of things have to happen at the right time. You've invested five years in the project, and now, on that day, it's all sitting on top of a large Titan-Centaur rocket. Both of the twin spacecraft were built here, at NASA JPL, then trucked to Florida, roughly three months before launch. That's when I went down there too, and where we put it all back together.

That's also where the team installed the radioisotope thermoelectric generators (RTGs) that convert the heat produced from the natural radioactive decay of plutonium into electricity to power the spacecraft, instruments, radio and on-board computers. The spacecraft fly too far from the sun to use solar panels. So, during that period, the entire team moved to Florida, some stayed here at JPL in Operations, but most of us were there in the summer of 1977. It was an amazing time.

What inspired you to study astrophysics and space science in the first place? I went to the University of Chicago in 1956, in the graduate program for physics. I wanted to study nuclear physics as that was the frontier back then. One year later, Sputnik was launched and heralded a new era of exploration—and the first major discovery of the Space Age—the Van Allen radiation belts around the Earth. It became apparent there was a lot to learn, if you could build the instruments and get them into space. As part of my work, I had the opportunity to launch scientific instruments looking at cosmic rays on a polar orbiting spacecraft.

So, after your Ph.D., you came to join Caltech in early 1960s, became chief scientist on the Voyager and then director. Did you always know you wanted to return to Voyager after finishing your time as director? I never left the Voyager mission, continued on right through, as chief scientist, while I was director. It was several years later that Voyager 1 reached the first milestone in the Voyager Interstellar Mission: the termination shock of the supersonic wind. Voyager 1 crossed the termination shock in December 2004 at about 94 AU from the Sun while Voyager 2 crossed it in August 2007 at about 84 AU. Then in August 2012, Voyager 1 finally entered Interstellar space.

And they're still out there. It's a long journey. Yes, they're still sending back signals. When Voyager launched, the Space Age was only 20 years old and there was no empirical evidence that spacecraft could last more than a few years. Voyager 1 and 2 have been up there for 40 years now, and we expect they'll deliver us valuable data until ~2030 when their nuclear power sources will no longer supply enough electrical energy to power critical subsystems.

What are the two main questions about the universe that the mission has answered thus far? Before Voyager, we thought the only active volcanoes were on Earth. Suddenly, on Jupiter's moon Io, we found 10 times more volcanic activity, and that's just on a moon. We're no longer as "terracentric" in our view of the bodies in the solar system. Time after time we were surprised by what we discovered. On Triton, a moon of Neptune, where the nitrogen is frozen, we found geysers erupting—at 40 degrees above absolute zero! We know that on Earth, water is present in three different states—frozen, liquid, and gas—and we've now found moons where other substances, like nitrogen and methane, possess similar states. Suddenly, because of Voyager, we realize how complex and interesting the planetary system is.

Is Voyager 2 still on course to go interstellar soon? We don't know exactly when, but the number I keep using is "a few years." But this is space exploration—it could be another surprise.

Talking of surprises, both Voyager spacecraft carry the 12-inch gold-plated copper disk which Carl Sagan and his committee put together as a greeting for other life forms. It was actually astrophysicist Frank Drake, on Carl Sagan's committee, that suggested the phonograph record for the Voyager mission, instead of a plaque which was onboard earlier missions: Pioneer 10 and 11.

Have you been disappointed that Voyager hasn't received a response from other interplanetary spacecraft? (Pauses) You mean Search for Extraterrestrial Intelligence?

Yes It will be 40,000 years before the Voyagers pass by other stars, so it was never expected there would be a response to the golden record during their operational lifetimes.

Perhaps we've been a bit dull as a prospect to anyone/thing out there? (Laughs) Maybe! [But] intelligent life is really very rare. There are now searches for microbial life, and that's to find the beginning of life. If a planet—or exoplanet—has the right thermal and geophysical conditions, with the development of scientific instruments it will be possible to study planets and exoplanets for evidence of microbial life, which is the initial step leading to intelligent life.

Back on firmer scientific footing for the final question: The Voyager spacecraft won't ever return to Earth, will they? No, in fact both spacecraft are escaping the solar system at a speed of about 3.6 AU per year. They'll continue communicating to Earth until the power runs out. The radioisotope thermoelectric generators (RTGs) have a radiation half-life of 88 years, and the spacecraft could keep going until ~2030.

What will happen then? Then Voyager 1 and 2 will both speed in their orbit around the center of the Milky Way Galaxy every 225 million years—until the Milky Way collides with another galaxy.

Source: www.zdnet.com

source Here: 40 Years of Voyager: A Q&A With Dr. Ed Stone at NASA JPL