MARS - Ancient Volcanoes on Mars Could Have Been the Place for Life

Ancient Volcanoes on Mars Could Have Been the Place for Life:



For decades, Mars has been the focal point of intense research. Beginning in the 1960s, literally dozens of robotic spacecraft, orbiters and rovers have explored Mars’ atmosphere and surface, looking for clues to the planet’s past. From this, scientists now know that billions of years ago, Mars was a warmer, wetter place. Not only did liquid water exist on its surface, but it is possible life existed there in some form as well.

Granted, some recent findings have cast some doubt in this, indicating that Mars’ surface may have been hostile to microbes. But a new study from an international team of scientists indicates that evidence life could be found in volcanic deposits. Specifically, they argue that within the massive geological structure known as Valles Marineris, there may be ancient volcanoes that have preserved ancient microbes.

The study, titled “Amazonian Volcanism Inside Valles Marineris on Mars“, recently appeared in the journal Earth and Planetary Science Letters. Led by Petr Brož of the Institute of Geophysics at the Czech Academy of Sciences (AVCR), the team examined Mars’ famous Valles Marineris region – a canyon system stretching for 4000 km (2485.5 mi) – for signs of recent geological activity, which opens up the possibility of there also being fossilized life there.

Valles Marineris, part of NASA World Wind map of Mars. Credit: NASA

The team began by examining the Coprates Chasma canyon, one of the lowest points in Valles Marineris, which is home to over 130 volcanoes and solidified lava flows. This consisted of analyzing high-resolution images of the region that were taken by NASA’s Mars Reconnaissance Orbiter (MRO), which revealed cones of basaltic lava (aka. scoria) and ash that measured around 400-meters (1300 ft) high.

After examining the cones’ surface patterns and morphological details, they confirmed that these were indeed the remains of lava volcanoes (and not mud volcanoes, which was another possibility). In addition, they also noted similarities between these cone and others on Mars where mud volcanism is not possible – as well as similarities with volcanic cones here on Earth.

As Ernst Hauber, a researcher from the Institute of Planetary Research at the German Aerospace Center (DLR) and a co-author on the study, explained in a AVCR press release:

“The spatial distribution of the cones also suggests their volcanic origin. They appear to occur more frequently along tectonic fractures that formed the trough in the surface and whose fracture interfaces continue into the subsurface, creating pathways for the magma to ascend.”

Even more surprising was the apparent age of the volcanoes, which was very young. On Mars, the main period of volcanic activity ended during Mars’ Hesperian Period – which ran from 3.7 to approximately 3.0 billion years ago. And while images acquired by the Mars Express mission have shown indications of younger volcanoes (occurring 500 million years ago), these tend to be located in volcanic provinces.

A colorized image of the surface of Mars taken by the Mars Reconnaissance Orbiter. The line of three volcanoes is the Tharsis Montes, with Olympus Mons to the northwest. Valles Marineris is to the east. Image: NASA/JPL-Caltech/ Arizona State University

A good example of this is the Tharsis Bulge, which is located several thousand km from the Coprates Chasma canyon. It is here that the Tharses Montes mountain chain is located, which consists of the shield volcanoes of Ascraeus Mons, Pavonis Mons and Arsia Mons. Olympus Mons, the tallest mountain in the Solar System (with an elevation of 22 km or 13.6 mi), is located at the edge of this region.

In contrast, the volcanic cones spotted in the Coprates Chasma canyon were estimates to be between 200 and 400 million years of age, placing them in the most recent geological period known as the Amazonian (3.0 billion years ago to the present day). This effectively demonstrates that these volcanoes formed late in Mars’ history and far away from volcanic areas like Tharsis and Elysium.

It also demonstrates that these volcanoes were not part of the original formation of Valles Marineris, which is believed to be related to the formation of the Tharsis Bulge. This all took place between the Noachian to Late Hesperian periods of Mars (ca. 3.5 billion years ago), which was the last time Mars experienced widespread geological activity.

Last, but not least, the team used the Compact Reconnaissance Imaging Spectrometer (CRISM) aboard the MRO to learn more about the mineral compositions of the region’s lava and volcanic cones. Once again, their findings proved to be surprising, and could indicate that the Coprates Chasma region is a suitable location to search for evidence of ancient life on Mars.

Image of young volcanoes at the base of Coprates Chasma on Mars, obtained by the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona

Essentially, the CRISM data indicated the presence of high-silica content minerals in the volcanic rock, which included opaline-like substances at one of the peaks. Opaline silicates, it should be noted, are water-bearing materials that are often produced by hydrothermal processes – where silicate structures form from supersaturated, hot solutions of minerals that cool to become solid.

On Earth, microorganisms are often found within opal deposits since they form in energy and mineral-rich environments, where microbial lifeforms thrive. The presence of these minerals in the Coprates Chasma region could therefore mean that ancient microorganisms once thrived there. Moreover, such organisms could also be fossilized within the mineral-rich lava rock, making it a tempting target for future research.

As Hauber indicated, the appeal of Coprates Chasma doesn’t end there, and future mission will surely want to make exploring this region a priority:

“Coprates Chasma is not just interesting with regard to the question of previous life on Mars. The region would also be an excellent landing site for future Mars Rovers. Here we could investigate many scientifically important and interesting topics. Analyzing samples for their elemental isotopic fractions would allow us to determine with far greater precision when the volcanoes were actually active.

“On the towering, steep walls, the geologic evolution of the Valles Marineris is presented to us almost like a history book – gypsum strata and layers of old, crustal rocks can be observed, as well as indications for liquid water trickling down the slopes even today during the warm season. That is as much Mars geology as you can get!”

Scientists were able to gauge the rate of water loss on Mars by measuring the ratio of water and HDO from today and 4.3 billion years ago. Credit: Kevin Gill

In other words, this low-lying region could be central to future studies that attempt to unlock the history and geological evolution of the Red Planet. The payoffs of studying this region not only include determining if Mars had life in the past, but when and how it went from being a warmer, wetter environment to the cold, dessicated landscape we know today.

In the future, NASA, the ESA, the China National Space Agency (CNSA) and Roscosmos all hope to mount additional robotic missions to Mars. In addition, NASA and even SpaceX hope to send crewed missions to the planet in the hopes of learning more about its past – and possibly future – habitability. Between its geological history, greater atmospheric pressure, and the possibility of fossilized life, one or more of these missions may be headed to Valles Marineris to have a look around.

Further Reading: The Czech Academy of Science, Earth and Planetary Science Letters

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MINI-SHUTTLE Dream Chaser Mini-Shuttle to Fly ISS Resupply Missions on ULA Atlas V

Dream Chaser Mini-Shuttle to Fly ISS Resupply Missions on ULA Atlas V:

Artist’s concept of the Sierra Nevada Corporation Dream Chaser spacecraft launching atop the United Launch Alliance Atlas V rocket in the 552 configuration on cargo missions to the International Space Station. Credit: ULA

The first two missions of the unmanned Dream Chaser mini-shuttle carrying critical cargo to the International Space Station (ISS) for NASA will fly on the most powerful version of the Atlas V rocket and start as soon as 2020, announced Sierra Nevada Corporation (SNC) and United Launch Alliance (ULA).

“We have selected United Launch Alliance’s Atlas V rocket to launch our first two Dream Chaser® spacecraft cargo missions,” said SNC of Sparks, Nevada.

Dream Chaser will launch atop the commercial Atlas V in its most powerful configuration, dubbed Atlas V 552, with five strap on solid rocket motors and a dual engine Centaur upper stage while protectively tucked inside a five meter diameter payload fairing – with wings folded.

Blast off of Dream Chaser loaded with over 5500 kilograms of cargo mass for the space station crews will take place from ULA’s seaside Space Launch Complex-41 on Cape Canaveral Air Force Station in Florida.

Sierra Nevada Corporation’s Dream Chaser spacecraft docks at the International Space Station.
Credits: Sierra Nevada Corporation

The unique lifting body design enables runway landings for Dream Chaser, similar to the NASA’s Space Shuttle at the Shuttle Landing Facility runway at NASA’s Kennedy Space Center in Florida.

The ULA Atlas V enjoys a 100% success rate. It has also been chosen by Boeing to ferry crews on piloted missions of their CST-100 Starliner astronaut space taxi to the ISS and back. The Centaur upper stage will be equipped with two RL-10 engines for both Dream Chaser and Starliner flights.

“SNC recognizes the proven reliability of the Atlas V rocket and its availability and schedule performance makes it the right choice for the first two flights of the Dream Chaser,” said Mark Sirangelo, corporate vice president of SNC’s Space Systems business area, in a statement.

“Humbled and honored by your trust in us,” tweeted ULA CEO Tory Bruno following the announcement.

Liftoff of the maiden pair of Dream Chaser cargo missions to the ISS are expected in 2020 and 2021 under the Commercial Resupply Services 2 (CRS2) contract with NASA.

Rendering of Launch of SNC’s Dream Chaser Cargo System Aboard an Atlas V Rocket. Credit: SNC

“ULA is pleased to partner with Sierra Nevada Corporation to launch its Dream Chaser cargo system to the International Space Station in less than three years,” said Gary Wentz, ULA vice president of Human and Commercial Systems.

“We recognize the importance of on time and reliable transportation of crew and cargo to Station and are honored the Atlas V was selected to continue to launch cargo resupply missions for NASA.”

By utilizing the most powerful variant of ULA’s Atlas V, Dream Chaser will be capable of transporting over 5,500 kilograms (12,000 pounds) of pressurized and unpressurized cargo mass – including science experiments, research gear, spare part, crew supplies, food, water, clothing and more per ISS mission.

“In addition, a significant amount of cargo, almost 2,000 kilograms is directly returned from the ISS to a gentle runway landing at a pinpoint location,” according to SNC.

“Dream Chaser’s all non-toxic systems design allows personnel to simply walk up to the vehicle after landing, providing immediate access to time-critical science as soon as the wheels stop.”

“ULA is an important player in the market and we appreciate their history and continued contributions to space flights and are pleased to support the aerospace community in Colorado and Alabama,” added Sirangelo.

Under the NASA CRS-2 contract awarded in 2016, Dream Chaser becomes the third ISS resupply provider, joining the current ISS commercial cargo vehicle providers, namely the Cygnus from Orbital ATK of Dulles, Virginia and the cargo Dragon from SpaceX of Hawthorne, California.

NASA decided to plus up the number of ISS commercial cargo providers from two to three for the critical task of ensuring the regular delivery of critical science, crew supplies, provisions, spare parts and assorted gear to the multinational crews living and working aboard the massive orbiting outpost.

NASA’s CRS-2 contracts run from 2019 through 2024 and specify six cargo missions for each of the three commercial providers.

By adding a new third provider, NASA simultaneously gains the benefit of additional capability and flexibility and also spreads out the risk.

Both SpaceX and Orbital ATK suffered catastrophic launch failures during ISS resupply missions, in June 2015 and October 2014 respectively, from which both firms have recovered.

Orbital ATK and SpaceX both successfully launched ISS cargo missions this year. Indeed a trio of Orbital ATK Cygnus spacecraft have already launched on the Atlas V, including the OA-7 resupply mission in March 2017.

Orbital ATK’s seventh cargo delivery flight to the International Space Station -in tribute to John Glenn- launched at 11:11 a.m. EDT April 18, 2017, on a United Launch Alliance Atlas V rocket from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida. Credit: Ken Kremer/kenkremer.com

Unlike the Cygnus which burns up on reentry and Dragon which lands via parachutes, the reusable Dream Chaser is capable of low-g reentry and runway landings. This is very beneficial for sensitive scientific experiments and allows much quicker access by researchers to time critical cargo.

1st Reused SpaceX Dragon cargo craft lifts off from Launch Complex 39A at NASA’s Kennedy Space Center in Florida at 5:07 p.m. June 3, 2017 on CRS-11 mission carrying 3 tons of research equipment, cargo and supplies to the International Space Station. Credit: Ken Kremer/kenkremer.com

Dream Chaser has been under development for more than 10 years. It was originally developed as a manned vehicle and a contender for NASA’s commercial crew vehicles. When SNC lost the bid to Boeing and SpaceX in 2014, the company opted to develop this unmanned variant instead.

A full scale test version of the original Dream Chaser is currently undergoing ground tests at NASA’s Armstrong Flight Research Center in California. Approach and landing tests are planned for this fall.

Other current cargo providers to the ISS include the Russian Progress and Japanese HTV vessels.

Watch for Ken’s onsite space mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Scale models of NASA’s Commercial Crew program vehicles and launchers; Boeing CST-100, Sierra Nevada Dream Chaser, SpaceX Dragon. Credit: Ken Kremer/kenkremer.com

Sierra Nevada Dream Chaser engineering test article in flight during prior captive-carry tests. Credit: NASA

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EARTH ORBIT - Ready to Leave Low Earth Orbit? Prototype Construction Begins for a Deep Space Habitat

Ready to Leave Low Earth Orbit? Prototype Construction Begins for a Deep Space Habitat:



In 2010, NASA accounted its commitment to mount a crewed mission to Mars by the third decade of the 21st century. Towards this end, they have working hard to create the necessary technologies – such as the Space Launch System (SLS) rocket and the Orion spacecraft. At the same time, they have partnered with the private sector to develop the necessary components and expertise needed to get crews beyond Earth and the Moon.

To this end, NASA recently awarded a Phase II contract to Lockheed Martin to create a new space habitat that will build on the lessons learned from the International Space Station (ISS). Known as the Deep Space Gateway, this habitat will serve as a spaceport in lunar orbit that will facilitate exploration near the Moon and assist in longer-duration missions that take us far from Earth.

The contract was awarded as part of the Next Space Technologies for Exploration Partnership (NextSTEP) program, which NASA launched in 2014. In April of 2016, as part of the second NextSTEP Broad Agency Announcement (NextSTEP-2) NASA selected six U.S. companies to begin building full-sized ground prototypes and concepts for this deep space habitat.

Artist’s impression of the Deep Space Gateway, currently under development by Lockheed Martin. Credit: NASA

Alongside such well-known companies like Bigelow Aerospace, Orbital ATK and Sierra Nevada, Lockheed Martin was charged with investigating habitat designs that would enhance missions in space near the Moon, and also serve as a proving ground for missions to Mars. Intrinsic to this is the creation of something that can take effectively integrate with SLS and the Orion capsule.

In accordance with NASA’s specifications on what constitutes an effective habitat, the design of the Deep Space Gateway must include a pressurized crew module, docking capability, environmental control and life support systems (ECLSS), logistics management, radiation mitigation and monitoring, fire safety technologies, and crew health capabilities.

The design specifications for the Deep Space Gateway also include a power bus, a small habitat to extend crew time, and logistics modules that would be intended for scientific research. The propulsion system on the gateway would rely on high-power electric propulsion to maintain its orbit, and to transfer the station to different orbits in the vicinity of the Moon when required.

With a Phase II contract now in hand, Lockheed Martin will be refining the design concept they developed for Phase I. This will include building a full-scale prototype at the Space Station Processing Facility at NASA’s Kennedy Space Center at Cape Canaveral, Florida, as well as the creation of a next-generation Deep Space Avionics Integration Lab near the Johnson Space Center in Houston.

Artist’s concept of space habitat operating beyond Earth and the Moon. Credit: NASA

As Bill Pratt, Lockheed Martin’s NextSTEP program manager, said in a recent press statement:

“It is easy to take things for granted when you are living at home, but the recently selected astronauts will face unique challenges. Something as simple as calling your family is completely different when you are outside of low Earth orbit. While building this habitat, we have to operate in a different mindset that’s more akin to long trips to Mars to ensure we keep them safe, healthy and productive.”

The full-scale prototype will essentially be a refurbished Donatello Multi-Purpose Logistics Module (MPLM), which was one of three large modules that was flown in the Space Shuttle payload bay and used to transfer cargo to the ISS. The team will also be relying on “mixed-reality prototyping”, a process where virtual and augmented reality are used to solve engineering issues in the early design phase.

“We are excited to work with NASA to repurpose a historic piece of flight hardware, originally designed for low Earth orbit exploration, to play a role in humanity’s push into deep space,” said Pratt. “Making use of existing capabilities will be a guiding philosophy for Lockheed Martin to minimize development time and meet NASA’s affordability goals.”

The Deep Space Gateway will also rely on the Orion crew capsule’s advanced capabilities while crews are docked with the habitat. Basically, this will consist of the crew using the Orion as their command deck until a more permanent command module can be built and incorporated into the habitat. This process will allow for an incremental build-up of the habitat and the deep space exploration capabilities of its crews.

Credit: NASA

As Pratt indicated, when uncrewed, the habitat will rely on systems that Lockheed Martin has incorporated into their Juno and MAVEN spacecraft in the past:

“Because the Deep Space Gateway would be uninhabited for several months at a time, it has to be rugged, reliable and have the robotic capabilities to operate autonomously. Essentially it is a robotic spacecraft that is well-suited for humans when Orion is present. Lockheed Martin’s experience building autonomous planetary spacecraft plays a large role in making that possible.”

The Phase II work will take place over the next 18 months and the results (provided by NASA) are expected to improve our understanding of what is needed to make long-term living in deep space possible. As noted, Lockheed Martin will also be using this time to build their Deep Space Avionics Integration Laboratory, which will serve as an astronaut training module and assist with command and control between the Gateway and the Orion capsule.

Beyond the development of the Deep Space Gateway, NASA is also committed to the creation of a Deep Space Transport – both of which are crucial for NASA’s proposed “Journey to Mars”. Whereas the Gateway is part of the first phase of this plan – the “Earth Reliant” phase, which involves exploration near the Moon using current technologies – the second phase will be focused on developing long-duration capabilities beyond the Moon.

NASA’s Journey to Mars. NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s. Credit: NASA/JPL

For this purpose, NASA is seeking to create a reusable vehicle specifically designed for crewed missions to Mars and deeper into the Solar System. The Deep Space Transport would rely on a combination of Solar Electric Propulsion (SEP) and chemical propulsion to transport crews to and from the Gateway – which would also serve as a servicing and refueling station for the spacecraft.

This second phase (the “Proving Ground” phase) is expected to culminate at the end of the 2020s, at which time a one-year crewed mission will take place. This mission will consist of a crew being flown to the Deep Space Gateway and back to Earth for the purpose of validating the readiness of the system and its ability to conduct long-duration missions independent of Earth.

This will open the door to Phase Three of the proposed Journey, the so-called “Earth Indepedent” phase. At this juncture, the habitation module and all other necessary mission components (like a Mars Cargo Vehicle) will be transferred to an orbit around Mars. This is expected to take place by the early 2030s, and will be followed (if all goes well) by missions to the Martian surface.

While the proposed crewed mission to Mars is still a ways off, the architecture is gradually taking shape. Between the development of spacecraft that will get the mission components and crew to cislunar space – the SLS and Orion – and the development of space habitats that will house them, we are getting closer to the day when astronauts finally set foot on the Red Planet!

Further Reading: NASA, Lockheed Martin

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DARK MATTER - Cosmologists Produce New Maps of Dark Matter Dynamics

Cosmologists Produce New Maps of Dark Matter Dynamics:

New maps of dark matter dynamics in the Universe have been produced by a team of international cosmologists. Using advanced computer modelling techniques, the research team has translated the distribution of galaxies into detailed maps of matter streams and velocities for the first time. The research was carried out by leading cosmologists from the UK, France and Germany.

Dr Florent Leclercq from the University of Portsmouth’s Institute of Cosmology and Gravitation said: “Dark matter is a substance of yet unknown nature that scientists believe makes up more than 80 per cent of the total mass of the Universe. As it does not emit or react to light, its distribution and evolution are not directly observable and have to be inferred.”

The researchers used legacy survey data obtained during 2000 – 2008 from the Sloan Digital Sky Survey (SDSS), a major three-dimensional survey of the Universe. The survey has deep multi-color images of one fifth of the sky and spectra for more than 900,000 galaxies.

The new dark matter maps cover the Northern Sky up to a distance of 600 megaparsecs, which is the equivalent of looking back about two billion years.

The researchers used a set of phase-space analysis tools and built on research from 2015, which reconstructed the initial conditions of the nearby Universe.

Dr Leclercq said: “Adopting a phase-space approach discloses a wealth of information, which was previously only analysed in simulations and thought to be inaccessible using observations.

“Accessing this information in galaxy surveys opens up new ways of assessing the validity of theoretical models in light of observations.”

The research is published in the Journal of Cosmology and Astroparticle Physics.

Credit: port.ac.uk

GALAXIES - Astronomers Find Young Galaxies that Appeared Soon After the Big Bang

Astronomers Find Young Galaxies that Appeared Soon After the Big Bang:

ASU astronomers Sangeeta Malhotra and James Rhoads, working with international teams in Chile and China, have discovered 23 young galaxies, seen as they were 800 million years after the Big Bang. The results from this sample have been recently published in the Astrophysical Journal.

Long ago, about 300,000 years after the beginning of the universe (the Big Bang), the universe was dark. There were no stars or galaxies, and the universe was filled with neutral hydrogen gas. In the next half-billion years or so, the first galaxies and stars appeared. Their energetic radiation ionized their surroundings, illuminating and transforming the universe.

This dramatic transformation, known as re-ionization, occurred sometime in the interval between 300 million years and 1 billion years after the Big Bang. Astronomers are trying to pinpoint this milestone more precisely, and the galaxies found in this study help in this determination.

“Before re-ionization, these galaxies were very hard to see, because their light is scattered by gas between galaxies, like a car’s headlights in fog,” Malhotra said. “As enough galaxies turn on and ‘burn off the fog’ they become easier to see. By doing so, they help provide a diagnostic to see how much of the ‘fog’ remains at any time in the early universe.”

To detect these galaxies, Malhotra and Rhoads have been using the Dark Energy Camera (DECam), one of the new powerful instruments in the astronomy field. DECam is installed at the National Optical Astronomy Observatory (NOAO)’s 4-meter Blanco Telescope, located at the Cerro Tololo Inter-American Observatory (CTIO), in northern Chile, at an altitude of 7,200 feet.

“Several years ago, we carried out a similar study using a 64-megapixel camera that covers the same amount of sky as the full moon,” Rhoads said. “DECam, by comparison, is a 570-megapixel camera and covers 15 times the area of the full moon in a single image.”

DECam was recently made even more powerful when it was equipped with a special narrowband filter, designed at ASU’s School of Earth and Space Exploration (SESE), primarily by Rhoads and Zhenya Zheng (who was a SESE postdoctoral fellow and is currently at the Shanghai Astronomical Observatory in China), with assistance from Alistair Walker of NOAO.

“We spent several months refining the design of the filter profile, optimizing the design to get maximum sensitivity in our search,” said Zheng, the lead author of this study.

The galaxy search using the ASU-designed filter and DECam is part of the ongoing “Lyman Alpha Galaxies in the Epoch of Reionization” project (LAGER). It is the largest uniformly selected sample that goes far enough back in the history of the universe to reach cosmic dawn.

“The combination of large survey size and sensitivity of this survey enables us to study galaxies that are common but faint, as well as those that are bright but rare, at this early stage in the universe,” said Malhotra.

Junxian Wang, a co-author on this study and the lead of the Chinese LAGER team, adds that “our findings in this survey imply that a large fraction of the first galaxies that ionized and illuminated the universe formed early, less than 800 million years after the Big Bang.”

The next steps for the team will be to build on these results. They plan to continue to search for distant star-forming galaxies over a larger volume of the universe and to further investigate the nature of some of the first galaxies in the universe. 

Credit: asu.edu

ASTRONOMY - Large, Distant Comets More Common Than Previously Thought

Large, Distant Comets More Common Than Previously Thought:

Comets that take more than 200 years to make one revolution around the sun are notoriously difficult to study. Because they spend most of their time far from our area of the solar system, many "long-period comets" will never approach the sun in a person's lifetime. In fact, those that travel inward from the Oort Cloud—a group of icy bodies beginning roughly 300 billion kilometers away from the sun—can have periods of thousands or even millions of years.

NASA's Wide-field Infrared Survey Explorer (WISE) spacecraft has delivered new insights about these distant wanderers. A team of astronomers led by James Bauer, a research professor of astronomy at the University of Maryland, found that there are about seven times more long-period comets measuring at least 1 kilometer across than previously predicted.

The researchers also found that long-period comets are, on average, nearly twice as large as "Jupiter family” comets, whose orbits are shaped by Jupiter’s gravity and have periods of less than 20 years. The findings were published July 14, 2017, in The Astronomical Journal.

"The number of comets speaks to the amount of material left over from the solar system's formation," Bauer said. "We now know that there are more relatively large chunks of ancient material coming from the Oort Cloud than we thought."

The Oort Cloud is too distant to be seen by current telescopes, but is thought to be a spherical distribution of small icy bodies at the outermost edge of the solar system. The density of comets within it is low, so the odds of comets colliding within it are low. Long-period comets that WISE observed probably got kicked out of the Oort Cloud millions of years ago. The observations were carried out in 2010 during the spacecraft's primary mission, before it was renamed NEOWISE and reactivated to target near-Earth objects (NEOs) in 2013.

"Our study is a rare look at objects perturbed out of the Oort Cloud," said Amy Mainzer, a co-author of the study based at NASA's Jet Propulsion Laboratory in Pasadena, California and principal investigator of the NEOWISE mission. "They are the most pristine examples of what the solar system was like when it formed."

Astronomers already had broader estimates of how many long-period and Jupiter family comets are in our solar system, but had no good way of measuring the sizes of long-period comets. This is because the cloud of gas and dust that surrounds each comet—known as a coma—appears hazy in images and obscures the comet’s nucleus.

By using WISE data that shows the infrared glow of the coma, the scientists were able to "subtract" the coma from each comet and estimate the size of the nucleus. The data came from WISE observations of 164 cometary bodies—including 95 Jupiter family comets and 56 long-period comets.

The results reinforce the idea that comets that pass by the sun more frequently tend to be smaller than those spending much more time away from the sun. That is because Jupiter family comets get more heat exposure, which causes volatile substances like water to sublimate and drag away other material from the comet’s surface as well.

"Our results mean there's an evolutionary difference between Jupiter family and long-period comets," Bauer said.

The existence of so many more long-period comets than predicted suggests that more of them have likely impacted planets, delivering icy materials from the outer reaches of the solar system.

Researchers also found clustered orbits among the long-period comets they studied, suggesting there could have been larger bodies that broke apart to form these groups.

The results will be important for assessing the likelihood of comets impacting our solar system's planets, including Earth.

"Comets travel much faster than asteroids, and some of them are very big," Mainzer said. "Studies like this will help us define what kind of hazard long-period comets may pose." 

NASA's Jet Propulsion Laboratory in Pasadena, California, managed and operated WISE for NASA's Science Mission Directorate in Washington, D.C. The NEOWISE project is funded by the Near-Earth Object Observation Program, now part of NASA’s Planetary Defense Coordination Office. The spacecraft was put into hibernation mode in 2011 after twice scanning the entire sky, thereby completing its main objectives. In September 2013, WISE was reactivated, renamed NEOWISE and assigned a new mission to assist NASA's efforts to identify potentially hazardous near-Earth objects.

Credit: umd.edu

THE UNIVERSE - International Research Team Sheds Light on the Earth’s ‘Twin Planet’

International Research Team Sheds Light on the Earth’s ‘Twin Planet’:

A research paper published by Nature Astronomy sheds light on the so far unexplored nightside circulation at the upper cloud level of Venus. Researchers from the Rhenish Institute for Environmental Research at the University of Cologne are part of an international research project which has now presented its preliminary findings. They discovered unexpected patterns of slow motion and abundant stationary waves in Venus’s nighttime sky.

Venus is often referred to as Earth's twin because both planets share a similar size and surface composition. Also, they both have atmospheres with complex weather systems. But that is about where the similarities end: Venus is one the most hostile places in our solar system. Its atmosphere consists of 96.5 percent carbon dioxide, with surface temperatures of constantly about 500 degrees Celsius. Venus is a slowly rotating planet – it needs about 243 terrestrial days to complete one rotation. We would expect its atmosphere to rotate with the same rhythm, but in fact it takes only four days. This phenomenon is called superrotation, and it causes substantial turbulences in the planet’s atmosphere. The scientists do not yet fully understand its origin and motor, but are working on an answer to this puzzle. The many waves in the planet's atmosphere may play an important role.

The preliminary research results were generated by an international collaboration headed by the Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA). Experts in space and astronautical science and astrophysics from universities and institutions in Japan, Spain, Italy, and Germany are cooperating in the project. From Germany, the Rhenish Institute for Environmental Research at the University of Cologne and the Center for Astronomy and Astrophysics at the Technical University of Berlin are involved.

The research team analysed data generated by the spacecraft Venus Express to investigate components of Venus’s complex atmosphere, including thermal measurements with regard to horizontal and vertical wave patterns. The data also included first global measurements from the tracking of individual features in thermal emission images at 3.8 and 5.0 µm (micrometer) during 2006–2008 and 2015.

Vertical information in unison with horizontal data help to understand the nature of the observed wave patterns. The vertical information from the VeRa instrument (an atmosphere experiment in Venus Express emits radio waves which the scientists then interpret) could help to identify the observed waves as buoyancy waves. This, in turn, is crucial for the analysis of atmospheric processes. 

Dr. Silvia Tellmann is Vice-Director of the Department of Planetary Research at the Rhenish Institute for Environmental Research at the University of Cologne. She is an expert on the structure, dynamics, and circulation of planetary atmospheres and a co-author of the study. ‘We were able to relate the stationary gravity waves found at higher altitudes with the surface elevations of Venus’, she says. ‘Hence, the waves can be explained with wind currents caused by topographical obstacles. We assume that these stationary waves are substantial for the continuity of the superrotation in the atmosphere of Venus.’

Credit: uni-koeln.de

Researchers Show How to Make Your Own Supernova

Researchers Show How to Make Your Own Supernova:

One of the most extreme astrophysical events, supernova explosions are the violent deaths of certain stars that scatter elements heavier than hydrogen and helium into surrounding space. Our own solar system is thought to have formed when a nearby supernova exploded distributing these elements into a cloud of hydrogen that then condensed to form our sun and the planets. In fact, the very atoms that make up our bodies were formed in the remnants of such an explosion.

Working in collaboration with Imperial College, London, and AWE Aldermaston the team, led in Oxford by Professor Gianluca Gregori of the Department of Physics, are currently demonstrating their research at the Royal Society Summer Science Exhibition, a week-long showcase of cutting-edge science from across the UK.

Witnessing and getting to grips with these experiments can help people to understand the inner workings of the Universe. Their ‘How to make a supernova’ exhibit will highlight how lasers like Orion can help us understand and appreciate the origins of the universe.

The team were able to mimic some the properties of these supernovae in the laboratory by using the most powerful lasers on earth, such as the ORION laser at AWE. Each output pulse from the laser only lasts for a few billionths of a second, but, in that time, the power it generates is equivalent to the output of the electricity grid of the whole planet. 

The extremes of density and temperature produced by the lasers allow scientists to study how the supernova acts when it expands into space, and can also provide insight into how high energy particles from space are produced, how the magnetic field in the galaxy formed, and what the interior of a giant planet might look like.

Dr Jena Meinecke, Junior Research Fellow at the University Oxford, said: ‘Lasers are so powerful today that we can actually recreate aspects of tiny supernovae that could fit in the palm of your hand! This allows us to answer fundamental questions such as 'What is the origin of magnetic fields in the universe?' Imagine the possibilities.

‘Our research is helping us better understand some of the most powerful natural processes known to humankind, and more importantly, the origins of our universe.’

Professor Justin Wark, Director of the Oxford Centre for High Energy Density Science (OxCHEDS), said: ‘The Royal Society Exhibition provides an excellent platform to tell the public about the exciting research that is going on in the field of laboratory astrophysics - in particular it is a great opportunity to enthuse young people, who will be the next generation of scientists.’

The ‘How to make a supernova’ research is on display at the Royal Society’s free annual Summer Science Exhibition until 9 July.

Surface of Mars Poses Danger to Life, Tests Show

Surface of Mars Poses Danger to Life, Tests Show:

The environment on Mars may be more harmful to Earth-based life forms than previously thought, experiments by Edinburgh scientists have shown. Researchers investigated the behavior of chemical compounds, called perchlorates, which are found on the surface of the red planet.

They found that, when exposed to UV light whilst in environmental conditions mimicking those on Mars, the chemicals can kill bacteria commonly carried by spacecraft.

Their findings could have implications for potential contamination from robotic and human exploration of Mars.

The study also suggested that the effect of perchlorates can be compounded by two other types of chemicals found on Mars’ surface, iron oxides and hydrogen peroxide.

In experiments in which all three were present, the combination led to a more than 10-fold increase in death of bacterial cells compared with perchlorates alone.

Scientists have speculated on the influence that perchlorates may have on the habitability of the planet, since their discovery there several years ago.

Researchers in the UK Centre for Astrobiology and School of Physics and Astronomy investigated the potential reactivity of perchlorates and their effect on Bacillus subtilis, a bacterium found on spacecraft and common in soils and rocks.

Their experiments showed that when magnesium perchlorate was exposed to UV radiation similar to that on Mars, it became capable of killing bacteria much more effectively than UV light alone.

At concentrations of perchlorate similar to those found on the Martian surface, cells of B. subtilis quickly died.

Although the Martian surface has been suspected for some time to have toxic effects, the latest study suggests that it may be highly damaging to living cells.

This is owing to a toxic mix of oxidants, iron oxides, perchlorates, and UV energy.

"Our findings have important implications for the possible contamination of Mars with bacteria and other materials from space missions. This should be taken into account in designing missions to Mars," said Jennifer Wadsworth of the UK Centre for Astrobiology and School of Physics and Astronomy.

Their study, funded by the Science and Technology Facilities Council, was published in Scientific Reports.

Credit: ed.ac.uk

Understanding Electron Transport in Solar Wind

Understanding Electron Transport in Solar Wind:

The sun constantly emits a flux of electrically charged particles into space, mostly protons and electrons, known as solar wind. This plasma affects the entire solar system, including Earth’s magnetic field and is therefore crucial to our understanding of space weather. Now, a University of Alabama in Huntsville (UAH) student is conducting a research into the transport of electrons and electron heat flux in the solar wind, which could provide new insights about this stream of energized particles emitted by the sun.

Bofeng Tang is a Ph.D. candidate in the Department of Space Science at UAH. He holds a master’s degree in physics and works under the supervision of National Academy of Sciences member Dr. Gary Zank, who serves as both chair of the department and director of UAH’s Center for Space Plasma and Aeronomic Research (CSPAR).

“I am hoping that Bofeng's research will clarify some aspects of the collisionless heat flux associated with the various solar wind electron populations, which will guide us then towards a better description of electron transport throughout the solar wind,” Zank told Astrowatch.net.

Tang has recently received a 2017/2018 NASA Earth and Space Science Fellowship (NESSF). The fellowship includes a $30,000 award and can be renewed for a total of three years.

NASA’s Heliophysics Division, which helps further the space agency’s research objective of investigating the sun and its interactions with the solar system, chose Tang’s study as one of only nine NESSF applications. The fellowship secures funding for Tang’s research and lets him concentrate on in-depth study of the transport of electrons in solar wind.

“The NASA NESSF is important to students, both in terms of the prestige that it typically carries (there are few awarded annually so it is a reflection on the student's potential and also the proposed problem), and in terms of guaranteed support for up to three years. This guarantee of support allows a student to attack a good problem in some depth,” Zank noted.

Backed by NESSF, Tang will focus on solving the problem of how solar wind electrons are transported in the solar wind. This question perplexes researchers and it is still far from being solved, in part because the electrons are quite collisional in the solar corona and below but tend to be collisionless further out from the sun, experiencing scattering primarily due to waves and turbulence.

“Understanding what waves and turbulence is responsible for the scattering of the various electron components (core, strahl, halo, energetic electrons) is still rather unclear. At this point, we cannot even accurately write down the correct set of equations that adequately describes how electrons are transported from one part of the solar wind to another,” Zank said.

Currently, the scientists do not have a fundamentally sound description of electrons in the solar wind. Tang’s research is expected to establish a better framework for understanding the solar wind dynamics implicitly advancing our understanding of space weather.

According to Zank, Tang’s study could also help improve the reputation of CSPAR when it comes to research in the field of physics.

“My Department of Space Science and the Center for Space Plasma and Aeronomic Research at UAH regard our students research as vitally important to making progress in the physics of the space environment and in space weather. This research helps build our growing reputation and the value and importance of it relates both to the fundamental science we explore and also the increased reputation of our students,” Zank concluded.

Supernova Forges Billowing, Tangled Knots of New Molecules

Supernova Forges Billowing, Tangled Knots of New Molecules:

Supernovas — the violent endings of the brief yet brilliant lives of massive stars — are among the most cataclysmic events in the cosmos. Though supernovas mark the death of stars, they also trigger the birth of new elements and the formation of new molecules. In February of 1987, astronomers witnessed one of these events unfold inside the Large Magellanic Cloud, a tiny dwarf galaxy located approximately 163,000 light-years from Earth.

Over the next 30 years, observations of the remnant of that explosion revealed never-before-seen details about the death of stars and how atoms created in those stars — like carbon, oxygen, and nitrogen — spill out into space and combine to form new molecules and dust. These microscopic particles may eventually find their way into future generations of stars and planets.

Recently, astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) to probe the heart of this supernova, named SN 1987A. ALMA’s ability to see remarkably fine details allowed the researchers to produce an intricate 3-D rendering of newly formed molecules inside the supernova remnant. These results are published in the Astrophysical Journal Letters.

The researchers also discovered a variety of previously undetected molecules in the remnant. These results appear in the Monthly Notices of the Royal Astronomical Society.

“When this supernova exploded, now more than 30 years ago, astronomers knew much less about the way these events reshape interstellar space and how the hot, glowing debris from an exploded star eventually cools and produces new molecules,” said Rémy Indebetouw, an astronomer at the University of Virginia and the National Radio Astronomy Observatory (NRAO) in Charlottesville. “Thanks to ALMA we can finally see cold ‘star dust’ as it forms, revealing important insights into the original star itself and the way supernovas create the basic building blocks of planets.”

Prior to ongoing investigations of SN 1987A, there was only so much astronomers could say about the impact of supernovas on their interstellar neighborhoods.

It was well understood that massive stars, those approximately 10 times the mass of our sun or more, ended their lives in spectacular fashion.

When these stars run out of fuel, there is no longer enough heat and energy to fight back against the force of gravity. The outer reaches of the star, once held up by the power of fusion, then come crashing down on the core with tremendous force. The rebound of this collapse triggers a powerful explosion that blasts material into space.

As the endpoint of massive stars, scientists have learned that supernovas have far-reaching effects on their home galaxies. To get a better understanding of these effects, Indebetouw helps break down the impact of these star-shattering events. “The reason some galaxies have the appearance that they do today is in large part because of the supernovas that have occurred in them,” he said. “Though less than ten percent of stars become supernovas, they nonetheless are key to the evolution of galaxies.”

Throughout the observable universe, supernovas are quite common, but since they appear – on average – about once every 50 years in a galaxy the size of the Milky Way, astronomers have precious few opportunities to study one from its first detonation to the point where it cools enough to form new molecules. Though SN 1987A is not in our home galaxy, it is still close enough for ALMA and other telescopes to study in fine detail.

This artist's illustration of Supernova 1987A reveals the cold, inner regions of the exploded star's remnants (red) where tremendous amounts of dust were detected and imaged by ALMA. This inner region is contrasted with the outer shell (blue), where the energy from the supernova is colliding (green) with the envelope of gas ejected from the star prior to its powerful detonation. Credit: A. Angelich; NRAO/AUI/NSF

For decades, radio, optical, and even X-ray observatories have studied SN 1987A, but obscuring dust in the remnant made it difficult to analyze the supernova’s innermost core. ALMA’s ability to observe at millimeter wavelengths – a region of the electromagnetic spectrum between infrared and radio light – make it possible to see through the intervening dust and gas. The researchers were then able to study the abundance and location of newly formed molecules – especially silicon monoxide (SiO) and carbon monoxide (CO), which shine brightly at the short submillimeter wavelengths that ALMA can perceive.

The new ALMA image and animation show vast new stores of SiO and CO in discrete, tangled clumps within the core of SN 1987A. Scientists previously modeled how and where these molecules would appear. With ALMA, the researchers finally were able to capture images with high enough resolution to confirm the structure inside the remnant and test those models.

Aside from obtaining this 3-D image of SN 1987A, the ALMA data also reveal compelling details about how its physical conditions have changed and continue to change over time. These observations also provide insights into the physical instabilities inside a supernova.

Earlier observations with ALMA verified that SN 1987A produced a massive amount of dust. The new observations provide even more details on how the supernova made the dust as well as the type of molecules found in the remnant.

“One of our goals was to observe SN 1987A in a blind search for other molecules,” said Indebetouw. “We expected to find carbon monoxide and silicon monoxide, since we had previously detected these molecules.” The astronomers, however, were excited to find the previously undetected molecules formyl cation (HCO+) and sulfur monoxide (SO).

“These molecules had never been detected in a young supernova remnant before,” noted Indebetouw. “HCO+ is especially interesting because its formation requires particularly vigorous mixing during the explosion.” Stars forge elements in discrete onion-like layers. As a star goes supernova, these once well-defined bands undergo violent mixing, helping to create the environment necessary for molecule and dust formation.

The astronomers estimate that about 1 in 1000 silicon atoms from the exploded star is now found in free-floating SiO molecules. The overwhelming majority of the silicon has already been incorporated into dust grains. Even the small amount of SiO that is present is 100 times greater than predicted by dust-formation models. These new observations will aid astronomers in refining their models.

These observations also find that ten percent or more of the carbon inside the remnant is currently in CO molecules. Only a few out of every million carbon atoms are in HCO+ molecules.

Even though the new ALMA observations shed important light on SN 1987A, there are still several questions that remain. Exactly how abundant are the molecules of HCO+ and SO? Are there other molecules that have yet to be detected? How will the 3-D structure of SN 1987A continue to change over time?

Future ALMA observations at different wavelengths may also help determine what sort of compact object — a pulsar or neutron star — resides at the center of the remnant. The supernova likely created one of these dense stellar objects, but as yet none has been detected.

Credit: nrao.edu