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What is Mars Made Of? | Composition of Planet Mars

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Mars is the “Red Planet” for a very good reason: its surface is made of a thick layer of oxidized iron dust and rocks of the same color. Maybe another name for Mars could be “Rusty.” But the ruddy surface does not tell the whole story of the composition of this world.

The dust that covers the surface of Mars is fine like talcum powder. Beneath the layer of dust, the Martian crust consists mostly of volcanic basalt rock. The soil of Mars also holds nutrients such as sodium, potassium, chloride and magnesium. The crust is about 30 miles (50 kilometers) thick.

Mars’ crust is thought to be one piece. Unlike Earth, the red planet has no tectonic plates that ride on the mantle to reshape the terrain. Since there is little to no movement in the crust, molten rock flowed to the surface at the same point for successive eruptions, building up into the huge volcanoes that dot the Martian surface.

Dusty, glass-rich sand dunes like these found just south of the north polar ice cap could cover much of Mars. (False color image)

Credit: NASA/JPL/University of Arizona

That doesn’t mean the crust sits quietly. New research has found that powerful landslides may speed down Martian slopes at up to 450 mph (725 km/h).

“The calculated velocity of landslides (often well in excess of 100 m/s and up to 200 m/s at peak) compares well with velocity estimates based on the run-up of the landslides on mounds,” researchers wrote in a study published in The European Physical Journal Plus.

“We conclude that ice may have been an important medium of lubrication of landslides on Mars, even in equatorial areas like Valles Marineris” (the Grand Canyon of Mars).

Any life that ever existed on Mars would have had to cope with the radiation, perhaps by thriving underground. While astronomers continue to search for past or present signs of biology on Mars, no convincing evidence has yet been found.

Evidence suggests there have been no volcanic eruptions for millions of years, however. The mantle that lies beneath the crust is largely dormant. It is made up primarily of silicon, oxygen, iron, and magnesium and probably has the consistency of soft rocky paste. It is probably about 900 to 1,200 miles (5,400 to 7,200 kilometers) thick, scientists say.

The center of Mars likely has a solid core composed of iron, nickel and sulfur. It is estimated to be between 1,800 and 2,400 miles (3,000 and 4,000 kilometers) in diameter. The core does not move, and therefore Mars lacks a planet-wide magnetic field. Instead, it has sporadic field lines that scientists have nicknamed “Christmas Lights.” Without a global magnetic field, radiation bombards the planet making it relatively inhospitable compared to Earth. [Infographic: Inside Planet Mars]

Mars is too cold for liquid water to exist for any length of time, but features on the surface suggest that water once flowed on Mars. Today, water exists in the form of ice in the soil, and in sheets of ice in the polar ice caps. The average temperature is about minus 80 degrees Fahrenheit (minus 60 degrees Celsius), although they can vary from minus 195 degrees F (minus 125 degrees C) near the poles during the winter to as much as 70 degrees F (20 degrees C) at midday near the equator.

NASA's Mars Reconnaissance Orbiter snapped this photo of a dust devil on the Red Planet on Feb. 16, 2012.

NASA’s Mars Reconnaissance Orbiter snapped this photo of a dust devil on the Red Planet on Feb. 16, 2012.

Credit: NASA/JPL-Caltech/Univ. of Arizona

The atmosphere of Mars is too thin to easily support life as we know it. It is about 95 percent carbon dioxide. The extremely thin air on Mars can also become very dusty. Dust from the planet’s surface is routinely kicked up into the atmosphere by giant dust devils— not unlike tornadoes on Earth. At times, the red planet can be partly or wholly consumed by dust storms.

At times, it even snows on Mars. The Martian snowflakes, made of carbon dioxide rather than water, are thought to be about the size of red blood cells. Flakes in the north measure between 8 to 22 microns and those in the south are just 4 to 13 microns.

Although the surface of Mars today is inhospitable for life as we know it, planetary scientists are finding signs that suggest the world may have been hospitable in the past. For instance, NASA’s Curiosity rover discovered the element boron, which plays a role in stabilizing sugars needed to make RNA, a key for life.

“Because borates may play an important role in making RNA — one of the building blocks of life — finding boron on Mars further opens the possibility that life could have once arisen on the planet,” Patrick Gasda, a postdoctoral researcher at Los Alamos National Laboratory in Los Alamos, New Mexico and lead author of the study, said in a statement.

“Essentially, this tells us that the conditions from which life could have potentially grown may have existed on ancient Mars, independent from Earth.”

Additional reporting by Nola Taylor Redd, Space.com contributor

Space.com is the premier source of space exploration, innovation and astronomy news, chronicling (and celebrating) humanity's ongoing expansion across the final frontier. We transport our visitors across the solar system and beyond through accessible, comprehensive coverage of the latest news and discoveries. For us, exploring space is as much about the journey as it is the destination. So from skywatching guides and stunning photos of the night sky to rocket launches and breaking news of robotic probes visiting other planets, at Space.com you’ll find something amazing every day.

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Astronomical Odds: Becoming an Astrophysicist Keeps Getting Tougher

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The dazzling star TYC 3203-450-1, in the constellation Lacerta, shines much closer to Earth than the distant galaxy NGC 7250, also visible in this Hubble Space Telescope image.

Paul Sutter is an astrophysicist at The Ohio State University and the chief scientist at COSI science center. Sutter is also host of “Ask a Spaceman” and “Space Radio,” and leads AstroTours around the world. Sutter contributed this article to Space.com’s Expert Voices: Op-Ed & Insights.

Ah, the life of an astrophysicist. The money. The parties. The paparazzi. No wonder so many young people flock to their nearest large research universities with stars in their eyes and dreams of Nobels in their hearts, buoyed by fantasies of solving the mystery of dark energy or cracking the enigma of quantum gravity. 

It’s true, sitting at the forefront of academic research is a unique, and sometimes thrilling, position. You are pushing the boundaries of human knowledge, and every experimental result, theoretical insight or recorded observation brings us closer to working out nature’s secrets. And for a moment, scientific discovery is a very private experience. Until you share your results with your colleagues in the community and the public in the wider world, you are the only human on the planet to know that fact, that insight, that datum. [8 Baffling Astronomy Mysteries]

And once you release that information, the volume of humanity’s understanding grows, most times by just a little, but sometimes by quite a lot. And at the end of your career, whether you end your journey as a young, freshly minted Ph.D. setting out into industry or a weathered and wizened emeritus professor, you can rest easy, knowing that academics and non-academics around the world are better off for your work.

Except, there are no jobs. At least, there are very few open faculty or research-lab positions for the people who want them (i.e., young Ph.D. holders). This isn’t new; academic jobs have always been on the rare side. But with the growth of university populations in the past decades, there is a glut of bachelors from all majors, including astronomy and physics. For example, there were roughly twice as many physics bachelor degrees awarded in 2015 than in 1995. And the increased undergraduate population has opened up funds for departments to host more graduate students, who do the majority of the teaching assistantship work. 

So, there are more Ph.D. grads created than ever before, but the same amount of — or fewer — long-term research jobs. Adding to the mix is the postdoctoral research position (often abbreviated as “postdoc”), a temporary job lasting two to five years in which you work to prove yourself as an independent researcher worthy of a faculty position.

The concept of a postdoc isn’t a bad one: How far can you fly without your advisor as the wind beneath your wings? A postdoc also gives you some experience working with a different group other than your graduate institution, so the interconnected web of worldwide researchers grows more tightly knit.

You would think that with a lot of Ph.D. holders and not a lot of long-term jobs, there wouldn’t be a lot of short-term postdoc positions. And that used to be the case; it was generally very tough and very competitive to get a postdoc, but if you did, you would most likely end up in a faculty position somewhere.

But in recent decades, with physical science research funding generally stalling or falling, it’s easier for a department, lab, or center to make a case for a term-limited grant with a small set of objectives than ask for the big bucks necessary for a lifetime, open-ended faculty position. The result: more postdoc positions. So now the field is in a state where about half the newly-minted Ph.D.’s slide right into a postdoc position.

Which is good! If you’re really into short-term positions. But now there are still a lot of faculty-wannabes in the system, and still not enough positions for them. There’s money for continued postdoc positions, creating a dangerous trend: Instead of the old “Ph.D. -> small chance of a postdoc -> faculty” pipeline, we have a “Ph.D. -> postdoc -> second postdoc -> maybe another postdoc -> small chance of a faculty job” system.

The result is the same: Most people with a Ph.D. in physics or astronomy won’t end up in a job in that field. This isn’t necessarily a bad thing, except that the harsh cutoff no longer comes when you’re a fresh-faced, probably single 20-something, able to easily and nimbly pivot to another career. Now, the people getting nudged out of the system are in their 30s, haven’t had a stable job for a decade, might be married, might want to start raising a family, and are generally making far less money than peers in their age and skill group.

And if you do get a faculty position, it’s another five years before your tenure review finally cements your career. Some unscrupulous universities even intentionally hire two junior faculty on a track for the same long-term professorship, taking a “two scientists enter, one scientist leaves” approach to fostering top talent.

For a graduate student or postdoc, this career path is not that rewarding. You get built up assuming you’re training for a career in academia, get a degree, then continue to be shunted from position to position. You get to do what you love, true, but with a clock always ticking in the background, reminding you that your time at the scientific forefront is probably nearing an end.

If that’s the system we have, then that’s the system we have, whether I think it’s fair or not. Some people think that a brief time as an active researcher is enough, and more power to them. And a bachelor’s or Ph.D. in physics or astronomy is a major asset for many kinds of jobs in industry, from finance to writing to consulting to Silicon Valley. Many science trainees are able to smoothly transition to a new life, making rewarding (both financially and mentally) lives for themselves. They also tend to make more money, which is nice.

Promising young students are more than welcome to take a chance at the academic wheel of fortune — assuming they know how the game is played. But we’re doing a very bad job at educating undergraduate and graduate students about the prospects of an academic career and what they might have to sacrifice (stability, money, relationships) in order to attain a professorship, and what other noble (rather than Nobel) options might await them with their degrees.

If we want the astrophysics community to thrive and attract new generations of scientists with new insights and new abilities — and especially if we want to encourage youngsters to explore STEM careers — then we first have to be honest about the state of our field.

Learn more by listening to the episode “Why can’t I be an astrophysicist?” on the “Ask a Spaceman” podcast, available on iTunes and on the web at http://www.askaspaceman.com. Thanks to @92Rufino and Vicki K. for the questions that led to this piece! Ask your own question on Twitter using #AskASpaceman or by following Paul @PaulMattSutter and facebook.com/PaulMattSutter.

Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com

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Enormous 'El Gordo' Galaxy Cluster Captured in Hubble Image

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The enormous “El Gordo” galaxy cluster, officially called ACT-CLJ0102-4915, has the mass of 3 million billion suns.

An incredible photo from the Hubble Space Telescope showcases an enormous galaxy cluster that weighs in at a whopping 3 million billion suns.

Due to its massive size, the galaxy cluster has been nicknamed “El Gordo” (Spanish for “the fat one”). Research suggests the cluster is the largest, hottest and brightest X-ray galaxy cluster ever discovered in the distant universe, NASA officials said in a statement

Galaxy clusters, groups of galaxies held together by gravity, are the biggest objects in the distant universe. These clusters take billions of years to form, as smaller groups of galaxies slowly move closer to each other, NASA officials said in the statement. 

The El Gordo galaxy cluster — officially known as ACT-CL J0102-4915 — is located more than 7 billion light-years from Earth. The cluster was first discovered in 2012 by a trio of telescopes, the European Southern Observatory’s Very Large Telescope, NASA’s Chandra X-ray Observatory and the Atacama Cosmology Telescope in Chile. These observations showed that El Gordo is actually the product of two galaxy clusters, which are in the process of colliding at a speed of millions of kilometers per hour, according to the statement. 

Dark matter and dark energy are believed to heavily influence the formation and evolution of galaxy clusters. Therefore, studying these clusters can help astronomers learn more about the elusive phenomenon, NASA officials said in the statement.

In fact, observations made by Hubble in 2014 showed that most of El Gordo’s mass is concealed in the form of dark matter, according to the statement. 

“Evidence suggests that El Gordo’s ‘normal’ matter — largely composed of hot gas that is bright in the X-ray wavelength domain — is being torn from the dark matter in the collision,” NASA officials said in the statement. “The hot gas is slowing down, while the dark matter is not.” 

The recent image, released by NASA on Jan. 16, was captured using Hubble’s Advanced Camera for Surveys and Wide-Field Camera 3. El Gordo is one of 41 giant galaxy clusters surveyed as part of the Reionization Lensing Cluster Survey (RELICS), which is a joint observing program led by the Hubble and Spitzer space telescopes, according to the NASA statement.

RELICS is designed to search for the brightest distant galaxies in the universe. This data will be used to identify faraway clusters of interest for further study by the James Webb Space Telescope, which is scheduled to launch sometime in the spring of 2019. 

Follow Samantha Mathewson @Sam_Ashley13. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

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New National Defense Strategy to Shed Light on Pentagon's Thinking About War in Space

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Defense Secretary Jim Mattis at U.S. Northern Command headquarters in Colorado Springs, Colorado.

WASHINGTON — Space and cyber warfare moved up the national security priority list during the Obama administration, and are expected to rank even higher under the Trump presidency.

Details on how the military views outer space and cyberspace as battlefronts in future wars should emerge in the national defense strategy that Defense Secretary Jim Mattis is expected to unveil Friday.

The national defense strategy — a forward-looking take on the challenges facing the U.S. military and how it is posturing itself to tackle those threats — is what used to be known as the QDR, or Quadrennial Defense Review. Congress last year determined that the QDR had no real value and asked the Pentagon to provide instead a more candid picture of its global commitments and requirements. The thinking is that lawmakers need to better understand what resources are needed for the military to fulfill those responsibilities. [The Most Powerful Space Weapons Concepts]

Andrew Philip Hunter, director of the Defense-Industrial Initiatives Group at the Center for Strategic and International Studies, said space and cyber are likely to feature prominently in Secretary Mattis’ first national defense strategy.

In the first year of the Trump administration, space, cyber and missile defense have “really risen on the scope as modernization priorities,” Hunter said Wednesday at a CSIS news conference. Although it is still not clear that the rhetoric about the importance of space and cyber will be matched by policy and funding.

The next Pentagon’s budget could be a show-me moment.

Space and cyber are “new investment categories that are trying to displace, to some extent, existing force structure,” he said. Defense leaders and strategists have said the military needs to invest in modern technology to improve data analysis, intelligence, surveillance and other information-centric capabilities. But most of the Pentagon’s budget today is spent on old-school weapons. This creates a dilemma for the administration as it tries to position the military to win in the so-called “great power competition” against Russia and China.

“In order to dramatically increase investment in space, the Air Force will probably be required to reduce the size of its tactical fighter fleet in order to be able to afford that kind of investment,” Hunter said. “All of the services are being forced to reallocate force structure into the cyber mission in a pretty major way. That’s hard to do.”

Shifting resources away from traditional military systems to emerging areas of warfare like space and cyber will require some heavy political muscle, Hunter said. “That means it has to come from the secretary,” he added. “Left to their own devices, it’s very hard for the services to make that tradeoff. And that’s why, if it’s not articulated in the strategy, if it’s not coming from the secretary, it’s probably not going to happen.”

The new strategy also may begin to answer questions that the space and arms-control communities have been asking for a long time, such as how the military plans to deter attacks as space becomes more militarized,

That is the “big, burning issue that has not been resolved,” said Todd Harrison, director of the Aerospace Security Project and senior fellow at CSIS.

“What are we going to do in space to reestablish or improve a stable deterrent posture?” Harrison asked. “We do not want to fight a war in space. That’s a war that’s not going to go well for anyone,” he insisted. “If you know anything about orbital mechanics and orbital debris, we don’t want it to go there.” Military leaders have made this point as well.

How the Pentagon would deter future enemies from launching attacks in space in unclear, said Harrison. “And we’re at a point now where deterrence is not as clear that it will work in space,” he said. “We’re worried about that. The Department of Defense is worried about that.” He wonders whether this strategy will help reestablish a stable “deterrence posture” in space.

In a leaked draft copy of the soon-to-be-released Nuclear Posture Review, the administration highlights the risks that, if a nuclear crisis erupted, U.S. adversaries would immediately target key strategic space assets such as missile-warning and command-and-control satellites.

“In the nuclear realm, it’s long been understood that if you’re actually getting into a nuclear conflict, that of course both sides are going to try to take out the space assets of the other,” Harrison said. “If you’re at that point, the gloves are off.”

That concern is not new, he noted. But deterrence in space has become more challenging for the United States because the same satellites are used for strategic and tactical missions. Classified communications and intelligence gathering satellites that were created to support a nuclear war routinely are employed in conventional missions.

What the Trump administration has to address, Harrison said, is “how do we architect these systems to do what we need them to do in a nuclear crisis, but also to be resilient to attack in a nonnuclear crisis?”

During the Cold War, only the Soviets posed a credible threat to U.S. space systems. “And we basically had an understanding between the two countries: ‘If you attack our space systems, we’re going to regard that as a prelude of a full-scale nuclear war.” The world today is different, and the U.S. military has become hugely dependent on space, even for low-intensity counterinsurgency operations.

“So why wouldn’t an adversary, even a non-state actor, try to disrupt these systems?” Harrison asked. “And we’ve seen evidence of that, things like jamming our satellite-communications signals in Iraq and Afghanistan,” he said. “It is a much more complicated deterrence problem that we have today. We can’t simply assume that the threat of nuclear retaliation is going to deter someone from interfering with our space systems.”

Deterrence is even more difficult as anonymous cyber attacks can disrupt satellites signals. “You can’t prove it,” said Harrison. “There’s not something blowing up. It’s photons interfering with one another,” he said. “Can we really deter those types of attacks anymore?” And when deterrence fails, “we need architectures in space that can withstand attacks, that are resilient.” Further, “we need a posture that makes us more credible that we can deter these types of actions.”

This story was provided by SpaceNews, dedicated to covering all aspects of the space industry.

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US Air Force's New Missile-Warning Satellite Launching Tonight: Watch It Live

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A United Launch Alliance Atlas V rocket carrying the new SBIRS GEO Fight 4 missile- warning satellite stands atop Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida ahead of a scheduled Jan. 18, 2018, launch.

The U.S. Air Force’s newest early-warning satellite for missile defense will launch into space from Florida tonight (Jan. 18), and you can watch the action live online.

A United Launch Alliance Atlas V rocket will launch the new military satellite, called the Space Based Infrared System (SBIRS) GEO Flight 4, from Space Launch Complex 41 at the Cape Canaveral Air Force Station. Liftoff is scheduled for 7:52 p.m. EST (0052 GMT on Jan. 19).

ULA will provide a live launch webcast beginning at 7:32 p.m. EST (0032 GMT). You can watch it live on Space.com here, or directly from ULA’s YouTube channel.

Built by Lockheed Martin, SBIRS GEO Flight 4 is the fourth member of a growing constellation of early-warning satellites designed to detect the launch of ballistic missiles from space. The satellites fly in geostationary orbits, and carry powerful scanning and infrared surveillance gear to track missile launches from orbit. 

The first two satellites, SBIRS GEO Flights 1 and 2, have been operational since 2013. SBIRS GEO Flight 3 launched in January 2017. Two other satellites, SBIRS GEO Flights 5 and 6, are expected to follow.

The Space Based Infrared System GEO Flight 4 missile-warning satellite is seen during assembly and test at Lockheed Martin’s satellite manufacturing facility in Sunnyvale, California.

Credit: Lockheed Martin

“SBIRS provides our military with timely, reliable and accurate missile warning and infrared surveillance information,” Tom McCormick, vice president of Lockheed Martin’s Overhead Persistent Infrared systems mission area, said in a Nov. 28 statement when SBIRS GEO Flight 4 was shipped to its Florida launch site. “We look forward to adding GEO Flight 4’s capabilities to the first line of defense in our nation’s missile defense strategy.”

Email Tariq Malik at tmalik@space.com or follow him @tariqjmalik and Google+. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

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