Saturday, November 29, 2014

NASA Saucer Named 'Best of What's New'

NASA Saucer Named 'Best of What's New':

This artist's concept shows the test vehicle for NASA's Low-Density Supersonic Decelerator (LDSD)
This artist's concept shows the test vehicle for NASA's Low-Density Supersonic Decelerator (LDSD), designed to test landing technologies for future Mars missions. Image credit: NASA/JPL-Caltech

› Full image and caption
NASA's "flying saucer" (aka Low-Density Supersonic Decelerator project, or LDSD for short) has earned recognition from Popular Science magazine as an innovation worthy of the publication's "Best of What's New" Award in the aerospace category.

The LDSD project successfully flew a rocket-powered, saucer-shaped test vehicle into near-space in late June from the U.S. Navy's Pacific Missile Range Facility on Kauai, Hawaii. The goal of this experimental flight test, the first of three planned for the project, was to determine if the balloon-launched, rocket-powered, saucer-shaped design could reach the altitudes and airspeeds needed to test two new breakthrough technologies destined for future Mars missions.

More information on the award winners is online at:

http://bestofwhatsnew.popsci.com

NASA's Space Technology Mission Directorate funds the LDSD mission, a cooperative effort led by NASA's Jet Propulsion Laboratory in Pasadena, California. NASA's Technology Demonstration Mission program manages the mission at NASA's Marshall Space Flight Center in Huntsville, Alabama. NASA's Wallops Flight Facility in Wallops Island, Virginia, coordinated support with the Pacific Missile Range Facility, provided the core electrical systems for the test vehicle, and coordinated the balloon and recovery services for the LDSD test. The California Institute of Technology in Pasadena manages JPL for NASA.

For more information about the LDSD space technology demonstration mission:

http://go.usa.gov/N5zm

Media Contact

DC Agle

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

agle@jpl.nasa.gov

David Steitz
NASA Headquarters, Washington
202-358-1730
david.steitz@nasa.gov

2014-404

NASA Issues 'Remastered' View of Jupiter's Moon Europa

NASA Issues 'Remastered' View of Jupiter's Moon Europa:

Europa's Stunning Surface The puzzling, fascinating surface of Jupiter's icy moon Europa looms large in this newly-reprocessed color view, made from images taken by NASA's Galileo spacecraft in the late 1990s. Image credit: NASA/JPL-Caltech/SETI Institute

› Full image and caption
Scientists have produced a new version of what is perhaps NASA's best view of Jupiter's ice-covered moon, Europa. The mosaic of color images was obtained in the late 1990s by NASA's Galileo spacecraft. This is the first time that NASA is publishing a version of the scene produced using modern image processing techniques.

The image is available at:

http://go.nasa.gov/1u36gqQ

This view of Europa stands out as the color view that shows the largest portion of the moon's surface at the highest resolution.

An earlier, lower-resolution version of the view, published in 2001, featured colors that had been strongly enhanced. The new image more closely approximates what the human eye would see. Space imaging enthusiasts have produced their own versions of the view using the publicly available data, but NASA has not previously issued its own rendition using near-natural color.

The image features many long, curving and linear fractures in the moon's bright ice shell. Scientists are eager to learn if the reddish-brown fractures, and other markings spattered across the surface, contain clues about the geological history of Europa and the chemistry of the global ocean that is thought to exist beneath the ice.

In addition to the newly processed image, a new video details why this likely ocean world is a high priority for future exploration.

The video is available at:

http://youtu.be/kz9VhCQbPAk

Hidden beneath Europa's icy surface is perhaps the most promising place in our solar system beyond Earth to look for present-day environments that are suitable for life. The Galileo mission found strong evidence that a subsurface ocean of salty water is in contact with a rocky seafloor. The cycling of material between the ocean and ice shell could potentially provide sources of chemical energy that could sustain simple life forms.

The Galileo mission was managed by NASA's Jet Propulsion Laboratory in Pasadena, California, for the agency's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology, Pasadena.

More information about Europa is available at:

http://solarsystem.nasa.gov/europa

Media Contact

Preston Dyches

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-7013

preston.dyches@jpl.nasa.gov

2014-406

Wednesday, November 19, 2014

Supernova Shock Waves, Neutron Stars, and Lobsters

Supernova Shock Waves, Neutron Stars, and Lobsters:



MSH 11-62 and G327.1-1.1*


A supernova that signals the death of a massive star sends titanic shock waves rumbling through interstellar space. An ultra-dense neutron star is usually left behind, which is far from dead, as it spews out a blizzard of high-energy particles. Two new images from NASA's Chandra X-ray Observatory provide fascinating views - including an enigmatic lobster-like feature - of the complex aftermath of a supernova.

When a massive star runs out of fuel resulting in a supernova explosion, the central regions usually collapse to form a neutron star. The energy generated by the formation of the neutron star triggers a supernova. As the outward-moving shock wave sweeps up interstellar gas, a reverse shock wave is driven inward, heating the stellar ejecta.

Meanwhile, the rapid rotation and intense magnetic field of the neutron star, a.k.a. a pulsar, combine to generate a powerful wind of high-energy particles. This so-called pulsar wind nebula can glow brightly in X-rays and radio waves.

More information at http://chandra.harvard.edu/photo/2014/msh11g327/index.html

-Megan Watzke, CXC

How Do Planets Form? Semarkona Meteorite Shows Some Clues

How Do Planets Form? Semarkona Meteorite Shows Some Clues:



Artist’s impression of a baby star still surrounded by a protoplanetary disc in which planets are forming. Credit: ESO


Artist’s impression of a baby star still surrounded by a protoplanetary disc in which planets are forming. Credit: ESO
It may seem all but impossible to determine how the Solar System formed, given that it happened roughly 4.5 billion years ago. Luckily, much of the debris that was left over from the formation process is still available today for study, circling our Solar System in the form of rocks and debris that sometimes make their way to Earth.

Among the most useful pieces of debris are the oldest and least altered type of meteorites, which are known as chondrites. They are built mostly of small stony grains, called chondrules, that are barely a millimeter in diameter.

And now, scientists are being provided with important clues as to how the early Solar System evolved, thanks to new research based on the the most accurate laboratory measurements ever made of the magnetic fields trapped within these tiny grains.

To break it down, chondrite meteorites are pieces of asteroids — broken off by collisions — that have remained relatively unmodified since they formed during the birth of the Solar System. The chondrules they contain were formed when patches of solar nebula – dust clouds that surround young suns – was heated above the melting point of rock for hours or even days.

The dust caught in these “melting events” was melted down into droplets of molten rock, which then cooled and crystallized into chondrules. As chondrules cooled, iron-bearing minerals within them became magnetized by the local magnetic field in the gas cloud. These magnetic fields are preserved in the chondrules right on up to the present day.



A slice of the NWA 5205 meteorite from the Sahara Desert displays wall-to-wall chondrules. Credit: Bob King


A slice of the NWA 5205 meteorite from the Sahara Desert displays wall-to-wall chondrules. Credit: Bob King
The chondrule grains whose magnetic fields were mapped in the new study came from a meteorite named Semarkona – named after the town in India where it fell in 1940.

Roger Fu of MIT – working under Benjamin Weiss – was the chief author of the study; with Steve Desch of Arizona State University’s School of Earth and Space Exploration attached as co-author.

According to the study, which was published this week in Science, the measurements they collected point to shock waves traveling through the cloud of dusty gas around the newborn sun as a major factor in solar system formation.

“The measurements made by Fu and Weiss are astounding and unprecedented,” says Steve Desch. “Not only have they measured tiny magnetic fields thousands of times weaker than a compass feels, they have mapped the magnetic fields’ variation recorded by the meteorite, millimeter by millimeter.”

The scientists focused specifically on the embedded magnetic fields captured by “dusty” olivine grains that contain abundant iron-bearing minerals. These had a magnetic field of about 54 microtesla, similar to the magnetic field at Earth’s surface (which ranges from 25 to 65 microtesla).

Coincidentally, many previous measurements of meteorites also implied similar field strengths. But it is now understood that those measurements detected magnetic minerals that were contaminated by the Earth’s own magnetic field, or even from the hand magnets used by the meteorite collectors.



Artist depiction of a protoplanetary disk permeated by magnetic fields. Objects in the foregrounds are millimeter-sized rock pellets known as chondrules. Credit: Hernán Cañellas


Artist depiction of a protoplanetary disk permeated by magnetic fields. Objects in the foregrounds are millimeter-sized rock pellets known as chondrules.
Credit: Hernán Cañellas
“The new experiments,” Desch says, “probe magnetic minerals in chondrules never measured before. They also show that each chondrule is magnetized like a little bar magnet, but with ‘north’ pointing in random directions.”

This shows, he says, that they became magnetized before they were built into the meteorite, and not while sitting on Earth’s surface. This observation, combined with the presence of shock waves during early solar formation, paints an interesting picture of the early history of our Solar System.

“My modeling for the heating events shows that shock waves passing through the solar nebula is what melted most chondrules,” Desch explains. Depending on the strength and size of the shock wave, the background magnetic field could be amplified by up to 30 times. “Given the measured magnetic field strength of about 54 microtesla,” he added, “this shows the background field in the nebula was probably in the range of 5 to 50 microtesla.”

There are other ideas for how chondrules might have formed, some involving magnetic flares above the solar nebula, or passage through the sun’s magnetic field. But those mechanisms require stronger magnetic fields than what has been measured in the Semarkona samples.

This reinforces the idea that shocks melted the chondrules in the solar nebula at about the location of today’s asteroid belt, which lies some two to four times farther from the sun than the Earth’s orbits.

Desch says, “This is the first really accurate and reliable measurement of the magnetic field in the gas from which our planets formed.”

Further Reading: ASU



About 

Author, freelance writer, educator, Taekwon-Do instructor, and loving hubby, son and Island boy!

OSIRIS-REx: The Audacious Plan To Scoop An Asteroid And Fly Back To Earth

OSIRIS-REx: The Audacious Plan To Scoop An Asteroid And Fly Back To Earth:

by Elizabeth Howell on November 18, 2014


We’ve been super-excited about the Philae landing recently, the first soft landing on a comet. But imagine if the spacecraft was equipped to bring a sample of Comet 67P/Churyumov–Gerasimenko back to Earth. What sort of secrets could we learn from examining the materials of the comet up close?

That dream will remain a dream for 67P, but guess what — if all goes to plan, that idea will execute for asteroid Bennu. Check out the new video above for more details on the audacious mission; below the jump is a brief mission description.

There is a mission expected to launch in 2016 called OSIRIS-REx that will spend two years flying to the asteroid to nab a sample, then will come back to Earth in 2023 to deliver it to scientists. This is exciting because asteroids are a sort of time capsule showing how the Solar System used to be in the early days, before gravity pulled rocks and ice together to gradually form the planets and moons that we have today.

“Scientists tell us that asteroid Bennu has been a silent witness to titanic events in the solar system’s 4.6 billion year history,” NASA wrote on a website commemorating the new video. “When it returns in 2023 with its precious cargo, OSIRIS-REx will help to break that silence and retrace Bennu’s journey.”

For more information on OSIRIS-REx, check out the mission’s website.



Artist's conception of asteroid Bennu from the NASA film "Bennu's Journey." Credit: NASA/YouTube (screenshot)


Artist’s conception of asteroid Bennu from the film “Bennu’s Journey.” Credit: NASA/University of Arizona/YouTube (screenshot)


About 

Elizabeth Howell is the senior writer at Universe Today. She also works for Space.com, Space Exploration Network, the NASA Lunar Science Institute, NASA Astrobiology Magazine and LiveScience, among others. Career highlights include watching three shuttle launches, and going on a two-week simulated Mars expedition in rural Utah. You can follow her on Twitter @howellspace or contact her at her website.

The Origins of Life Could Indeed Be “Interstellar”

The Origins of Life Could Indeed Be “Interstellar”:



Star-forming region in interstellar space. Image credit: NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration


Star-forming region in interstellar space.
Image credit: NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration
Some of science’s most pressing questions involve the origins of life on Earth. How did the first lifeforms emerge from the seemingly hostile conditions that plagued our planet for much of its history? What enabled the leap from simple, unicellular organisms to more complex organisms consisting of many cells working together to metabolize, respire, and reproduce? In such an unfamiliar environment, how does one even separate “life” from non-life in the first place?

Now, scientists at the University of Hawaii at Manoa believe that they may have an answer to at least one of those questions. According to the team, a vital cellular building block called glycerol may have first originated via chemical reactions deep in interstellar space.


Glycerol is an organic molecule that is present in the cell membranes of all living things. In animal cells this membrane takes the form of a phospholipid bilayer, a dual-layer membrane that sandwiches water-repelling fatty acids between outer and inner sheets of water-soluble molecules. This type of membrane allows the cell’s inner aqueous environment to remain separate and protected from its external, similarly watery world. Glycerol is a vital component of each phospholipid because it forms the backbone between the molecule’s two characteristic parts: a polar, water-soluble head, and a non-polar, fatty tail.

Many scientists believe that cell membranes such as these were a necessary prerequisite to the evolution of multicellular life on Earth; however, their complex structure requires a very specific environment – namely, one low in calcium and magnesium salts with a fairly neutral pH and stable temperature. These carefully balanced conditions would have been hard to come by on the prehistoric Earth.

Icy bodies born in interstellar space offer an alternative scenario. Scientists have already discovered organic molecules such as amino acids and lipid precursors in the Murchison meteorite that landed in Australia in 1969. Although the idea remains controversial, it is possible that glycerol could have been brought to Earth in a similar manner.



The Murchison Meteorite. Image credit: James St. John


The Murchison Meteorite.
Image credit: James St. John
Meteors typically form from tiny crumbs of material in cold molecular clouds, regions of gaseous hydrogen and interstellar dust that serve as the birthplace of stars and planetary systems. As they move through the cloud, these grains accumulate layers of frozen water, methanol, carbon dioxide, and carbon monoxide. Over time, high-energy ultraviolet radiation and cosmic rays bombard the icy fragments and cause chemical reactions that enrich their frozen cores with organic compounds. Later, as stars form and ambient material falls into orbit around them, the ices and the organic molecules they contain are incorporated into larger rocky bodies such as meteors. The meteors can then crash into planets like ours, potentially seeding them with building blocks of life.

In order to test whether or not glycerol could be created by the high-energy radiation that typically bombards interstellar ice grains, the team at the University of Hawaii designed their own meteorites: small bits of icy methanol cooled to 5 degrees Kelvin. After blasting their model ices with energetic electrons meant to mimic the effects of cosmic rays, the scientists found that some molecules of methanol within the ices did, in fact, transform into glycerol.

While this experiment appears to be a success, scientists realize that their laboratory models do not exactly replicate conditions in interstellar space. For instance, methanol traditionally makes up only about 30% of the ice in space rocks. Future work will investigate the effects of high-energy radiation on model ices made primarily of water. High-energy electrons fired in a lab are also not a perfect substitute for true cosmic rays and do not represent effects on ice that may result from ultraviolet radiation in interstellar space.

More research is necessary before scientists can draw any global conclusions; however, this study and its predecessors do provide compelling evidence that life as we know it truly could have come from above.



About 

Vanessa earned her bachelor's degree in Astronomy and Physics in 2009 from Wheaton College in Massachusetts. Her credits in astronomy include observing and analyzing eclipsing binary star systems and taking a walk on the theory side as a NSF REU intern, investigating the impact of type 1a supernovae on the expansion of the Universe. In her spare time she enjoys writing about astrophysics and cosmology, making delicious vegetarian meals, taking adventures with her husband and/or Nikon D50, and saving the world.

Shortly After Mars Comet, NASA’s New Red Planet Spacecraft Officially Starts Mission

Shortly After Mars Comet, NASA’s New Red Planet Spacecraft Officially Starts Mission:



MAVEN's Ultraviolet Imaging Spectrograph (IUVS) uses limb scans to map the chemical makeup and vertical structure across Mars' upper atmosphere. It detected strong enhancements of magnesium and iron from ablating incandescing dust from Comet Siding Spring. Credit: NASA


MAVEN’s Ultraviolet Imaging Spectrograph (IUVS) uses limb scans to map the chemical makeup and vertical structure across Mars’ upper atmosphere. It detected strong enhancements of magnesium and iron from ablating incandescing dust from Comet Siding Spring. Credit: NASA
NASA’s newest Mars spacecraft is “go” for at least a year — and potentially longer. After taking a time-out from commissioning to observe Comet Siding Spring whizz by the Red Planet in October, the Mars Atmosphere and Volatile Evolution (MAVEN) officially began its science mission Monday (Nov. 17). And so far things are going well.

“From the observations made both during the cruise to Mars and during the transition phase, we know that our instruments are working well,” stated principal investigator Bruce Jakosky, who is with NASA’s Goddard Space Flight Center in Maryland. “The spacecraft also is operating smoothly, with very few ‘hiccups’ so far. The science team is ready to go.”

MAVEN arrived in orbit Sept. 16 after facing down and overcoming a potential long delay for its mission. NASA and other federal government departments were in shutdown while MAVEN was in final launch preparations, but the mission received a special waiver because it is capable of communicating with the rovers on Mars. Given the current relay spacecraft are aging, MAVEN could serve as the next-generation spacecraft if those ones fail.



Three views of an escaping atmosphere, obtained by MAVEN’s Imaging Ultraviolet Spectrograph. By observing all of the products of water and carbon dioxide breakdown, MAVEN's remote sensing team can characterize the processes that drive atmospheric loss on Mars. Image Credit: University of Colorado/NASA


Three views of an escaping atmosphere, obtained by MAVEN’s Imaging Ultraviolet Spectrograph. By observing all of the products of water and carbon dioxide breakdown, MAVEN’s remote sensing team can characterize the processes that drive atmospheric loss on Mars.
Image Credit:
University of Colorado/NASA
But that’s providing that MAVEN can last past the next year in terms of hardware and funding. Meanwhile, its primary science mission is better understanding how the atmosphere of Mars behaves today and how it has changed since the Red Planet was formed.

“The nine science instruments will observe the energy from the Sun that hits Mars, the response of the upper atmosphere and ionosphere, and the way that the interactions lead to loss of gas from the top of the atmosphere to space,” Jakosky added.

“Our goal is to understand the processes by which escape to space occurs, and to learn enough to be able to extrapolate backwards in time and determine the total amount of gas lost to space over time. This will help us understand why the Martian climate changed over time, from an early warmer and wetter environment to the cold, dry planet we see today.”

Source: NASA



About 

Elizabeth Howell is the senior writer at Universe Today. She also works for Space.com, Space Exploration Network, the NASA Lunar Science Institute, NASA Astrobiology Magazine and LiveScience, among others. Career highlights include watching three shuttle launches, and going on a two-week simulated Mars expedition in rural Utah. You can follow her on Twitter @howellspace or contact her at her website.

Warm, Flowing Water on Mars Was Episodic, Study Suggests

Warm, Flowing Water on Mars Was Episodic, Study Suggests:



Credit: NASA/MRO/Rendering: James Dickson, Brown University


New research suggests that warmer temperatures and water flow on ancient Mars were likely related to periodic volcanism early in the planet’s history. Credit: NASA/MRO/Rendering: James Dickson, Brown University
Though the surface of Mars is a dry, dessicated and bitterly cold place today, it is strongly believed that the planet once had rivers, streams, lakes, and flowing water on its surface. Thanks to a combination of spacecraft imagery, remote sensing techniques and surface investigations from landers and rovers, ample evidence has been assembled to support this theory.

However, it is hard to reconcile this view with the latest climate models of Mars which suggest that it should have been a perennially cold and icy place. But according to a new study, the presence of warm, flowing water may have been an episodic occurrence, something that happened for decades or centuries when the planet was warmed sufficiently by volcanic eruptions and greenhouse gases.

The study, which was conducted by scientists from Brown University and Israel’s Weizmann Institute of Science, suggests that warmth and water flow on ancient Mars were probably episodic, related to brief periods of volcanic activity that spewed tons of greenhouse-inducing sulfur dioxide gas into the atmosphere.

The work combines the effect of volcanism with the latest climate models of early Mars and suggests that periods of temperatures warm enough for water to flow likely lasted for only tens or hundreds of years at a time.

The notion that Mars had surface water predates the space age by centuries. Long before Percival Lowell’s observed what he thought were “canals” on the Martian surface in 1877, the polar ice caps and dark spots on the surface were being observed by astronomers who thought that they were indications of liquid water.



Curiosity found evidence of an ancient, flowing stream on Mars at a few sites, including the "Hottah" rock outcrop pictured here. Credit: NASA/JPL


Curiosity found evidence of an ancient, flowing stream on Mars at a few sites, including the “Hottah” rock outcrop pictured here. Credit: NASA/JPL
But with all that’s been learned about Mars in recent years, the mystery of the planet’s ancient water has only deepened. The latest generation of climate models for early Mars suggests that the atmosphere was too thin to heat the planet enough for water to flow. Billions of years ago, the sun was also much dimmer than it is today, which further complicates this picture of a warmer early Mars.

“These new climate models that predict a cold and ice-covered world have been difficult to reconcile with the abundant evidence that water flowed across the surface to form streams and lakes,” said James W. Head, professor of earth, environmental and planetary sciences at Brown University and co-author of the new paper with Weizmann’s Itay Halevy. “This new analysis provides a mechanism for episodic periods of heating and melting of snow and ice that could have each lasted decades to centuries.”

Halevy and Head explored the idea that heating may have been linked to periodic volcanism. Many of the geological features that suggest water was flowing on the Martian surface have been dated to 3.7 billion years ago, a time when massive volcanoes are thought to have been active.

And whereas on Earth, widespread volcanism has often led to global dimming rather than warming – on a count of sulfuric acid particles reflecting the sun’s rays – Head and Halevy think the effects may have been different in Mars’ dusty atmosphere.

To test this theory, they created a model of how sulfuric acid might react with the widespread dust in the Martian atmosphere. The work suggests that those sulfuric acid particles would have glommed onto dust particles and reduced their ability to reflect the sun’s rays. Meanwhile, sulfur dioxide gas would produced enough of greenhouse effect to warm the Martian equatorial region so that water could flow.



Image of the McMurdo Dry Valleys, Antarctica, acquired by Landsat 7’s Enhanced Thematic Mapper plus (ETM+) instrument. Credit: NASA/EO


Image of the McMurdo Dry Valleys, Antarctica, acquired by Landsat 7’s Enhanced Thematic Mapper plus (ETM+) instrument. Credit: NASA/EO
Head has been doing fieldwork for years in Antarctica and thinks the climate on early Mars may have been very similar to what he has observed in the cold, desert-like.

“The average yearly temperature in the Antarctic Dry Valleys is way below freezing, but peak summer daytime temperatures can exceed the melting point of water, forming transient streams, which then refreeze,” Head said. “In a similar manner, we find that volcanism can bring the temperature on early Mars above the melting point for decades to centuries, causing episodic periods of stream and lake formation.”

As that early active volcanism on Mars ceased, so did the possibility of warmer temperatures and flowing water.

According to Head, this theory might also help in the ongoing search for signs that Mars once hosted life. If it ever did exist, this new research may offer clues as to where the fossilized remnants ended up.

“Life in Antarctica, in the form of algal mats, is very resistant to extremely cold and dry conditions and simply waits for the episodic infusion of water to ‘bloom’ and develop,” he said. “Thus, the ancient and currently dry and barren river and lake floors on Mars may harbor the remnants of similar primitive life, if it ever occurred on Mars.”

The research was published in Nature Geoscience.

Further Reading: Brown University



About 

Author, freelance writer, educator, Taekwon-Do instructor, and loving hubby, son and Island boy!

Amazingly Detailed New Maps of Asteroid Vesta

Amazingly Detailed New Maps of Asteroid Vesta:



Artist's concept of the Dawn spacecraft arriving at Vesta. Image credit: NASA/JPL-Caltech


Artist’s concept of the Dawn spacecraft arriving at Vesta. Credit: NASA/JPL-Caltech
Vesta is one of the largest asteroids in the Solar System. Comprising 9% of the mass in the Asteroid Belt, it is second in size only to the dwarf-planet Ceres. And now, thanks to data obtained by NASA’s Dawn spacecraft, Vesta’s surface has been mapped out in unprecedented detail.
These high-resolution geological maps reveal the variety of Vesta’s surface features and provide a window into the asteroid’s history.

“The geologic mapping campaign at Vesta took about two-and-a-half years to complete, and the resulting maps enabled us to recognize a geologic timescale of Vesta for comparison to other planets,” said David Williams of Arizona State University.


Geological mapping is a technique used to derive the geologic history of a planetary object from detailed analysis of surface morphology, topography, color and brightness information. The team found that Vesta’s geological history is characterized by a sequence of large impact events, primarily by the Veneneia and Rheasilvia impacts in Vesta’s early history and the Marcia impact in its late history.

The geologic mapping of Vesta was made possible by the Dawn spacecraft’s framing camera, which was provided by the Max Planck Institute for Solar System Research of the German Max Planck Society and the German Aerospace Center.  This camera takes panchromatic images and seven bands of color-filtered images, which are used to create topographic models of the surface that aid in the geologic interpretation.

A team of 14 scientists mapped the surface of Vesta using Dawn data. The study was led by three NASA-funded participating scientists: Williams; R. Aileen Yingst of the Planetary Science Institute; and W. Brent Garry of the NASA Goddard Spaceflight Center.



This high-res geological map of Vesta is derived from Dawn spacecraft data. Brown colors represent the oldest, most heavily cratered surface. Credit: NASA/JPL-Caltech/ASU


This high-res geological map of Vesta is derived from Dawn spacecraft data. Credit: NASA/JPL-Caltech/ASU
The brown colored sections of the map represent the oldest, most heavily cratered surface. Purple colors in the north and light blue represent terrains modified by the Veneneia and Rheasilvia impacts, respectively. Light purples and dark blue colors below the equator represent the interior of the Rheasilvia and Veneneia basins. Greens and yellows represent relatively young landslides or other downhill movement and crater impact materials, respectively.

The map indicates the prominence of impact events – such as the Veneneia, Rheasilvia and Marcia impacts, respectively – in shaping the asteroid’s surface. It also indicates that the oldest crust on Vesta pre-dates the earliest Veneneia impact. The relative timescale is supplemented by model-based absolute ages from two different approaches that apply crater statistics to date the surface.

“This mapping was crucial for getting a better understanding of Vesta’s geological history, as well as providing context for the compositional information that we received from other instruments on the spacecraft: the visible and infrared (VIR) mapping spectrometer and the gamma-ray and neutron detector (GRaND),” said Carol Raymond, Dawn’s deputy principal investigator at NASA’s Jet Propulsion Laboratory in Pasadena, California.

The objective of NASA’s Dawn mission is to characterize the two most massive objects in the main asteroid belt between Mars and Jupiter – Vesta and the dwarf planet Ceres.



These Hubble Space Telescope images of Vesta and Ceres show two of the most massive asteroids in the asteroid belt, a region between Mars and Jupiter. Credit: NASA/European Space Agency


These Hubble Space Telescope images of Vesta and Ceres show two of the most massive asteroids in the asteroid belt. Credit: NASA/European Space Agency
Asteroids like Vesta are remnants of the formation of the solar system, giving scientists a peek at its early history. They can also harbor molecules that are the building blocks of life and reveal clues about the origins of life on Earth. Hence why scientists are eager to learn more about its secrets.

The Dawn spacecraft was launched in September of 2007 and orbited Vesta between July 2011 and September 2012. Using ion propulsion in spiraling trajectories to travel from Earth to Vesta, Dawn will orbit Vesta and then continue on to orbit the dwarf planet Ceres by April 2015.

The high resolution maps were included with a series of 11 scientific papers published this week in a special issue of the journal Icarus. The Dawn spacecraft is currently on its way to Ceres, the largest object in the asteroid belt, and will arrive at Ceres in March 2015.

Further Reading: NASA



About 

Author, freelance writer, educator, Taekwon-Do instructor, and loving hubby, son and Island boy!

Lunar Mission One Wants To Crowdfound A Robotic Moon Lander

Lunar Mission One Wants To Crowdfound A Robotic Moon Lander:

Just hours after announcing that it plans to put a robotic lander on the moon in the next decade, the British-led group Lunar Mission One is already a sixth of a way to its £600,000 (US$940,000) initial crowdfunding goal.

The money is intended to jumpstart the project and move it into more concrete stages after seven years of quiet, weekend work, the group said on its Kickstarter page.

“We’ve reached the limit of what we can do part-time. The next three years are going to be hard, full-time work to set the project up. We need to confirm and agree the lunar science and develop the instrument package,” the page read.



Artist's conception of Lunar Mission One's robotic lander touching down on the surface. Credit: Lunar Missions Ltd.


Artist’s conception of Lunar Mission One’s robotic lander touching down on the surface. Credit: Lunar Missions Ltd.
“We need to plan and research the online public archive. We need to get commercial partners on board to design and develop the lunar landing module and the drilling mechanism. We need to pilot the education programme. We need to prepare the sales and marketing campaign for our memory boxes. And we need to do all of this globally.”

Among the rewards is something called a “digital memory box”, where you can upload your favorite sounds to be placed on the spacecraft. The group also plans to offer a little bit of physical space to put a strand of your hair along with the small digital archive.

And what does the group want to do there? Drill. It would place the lander at the Moon’s south pole and push down at least 20 meters (65 feet), potentially as far as 100 meters (328 feet), to learn more about the Moon’s history.



Artist's conception of a moon drill that could potentially be used by Lunar Mission One's lunar lander. Credit: Lunar Missions Ltd.


Artist’s conception of a moon drill that could potentially be used by Lunar Mission One’s lunar lander. Credit: Lunar Missions Ltd.
“By doing this, we will access lunar rock dating back up to 4.5 billion years to discover the geological composition of the Moon, the ancient relationship it shares with our planet and the effects of asteroid bombardment,” the group wrote. “Ultimately, the project will improve scientific understanding of the early Solar System, the formation of our planet and the Moon, and the conditions that initiated life on Earth.”

Private ideas for bold missions is something we’ve heard about repeatedly in the last few years, with initiatives ranging from the Mars One mission to send people on a one-way mission to the Red Planet, to the potential asteroid-mining ventures Planetary Resources and Deep Space Initiatives. As with these other ventures, the nitty gritty in terms of costs, systems and mission plans is still being worked out. This coupled with the long timelines to get these ventures off the ground means that success is not necessarily a guarantee.

Lunar Mission One, however, does have an experienced space hand helping it out: RAL Space, who the Kickstarter campaign page says has helped out with 200 missions. That’s including the high-profile Philae lander that just landed on Comet 67P/Churyumov–Gerasimenko last week and did a brief surge of science before going into hibernation.

For more information on the mission, check out their leading team here and the official website here.



About 

Elizabeth Howell is the senior writer at Universe Today. She also works for Space.com, Space Exploration Network, the NASA Lunar Science Institute, NASA Astrobiology Magazine and LiveScience, among others. Career highlights include watching three shuttle launches, and going on a two-week simulated Mars expedition in rural Utah. You can follow her on Twitter @howellspace or contact her at her website.

Observing Challenge: Watch Asteroid 3 Juno Occult a +7th Magnitude Star Tonight

Observing Challenge: Watch Asteroid 3 Juno Occult a +7th Magnitude Star Tonight:



Stellarium


The position of 3 Juno on the morning of November 20th during the occultation as seen from Portland, Maine. Credit: Stellarium.
One of the better asteroid occultations of 2014 is coming right up tonight, and Canadian and U.S. observers in the northeast have a front row seat.

The event occurs in the early morning hours of Thursday, November 20th, when the asteroid 3 Juno occults the 7.4 magnitude star SAO 117176. The occultation kicks off in the wee hours as the 310 kilometre wide “shadow” of 3 Juno touches down and crosses North America from 6:54 to 6:57 Universal Time (UT), which is 12:54 to 12:57 AM Central, or 1:54 to 1:57 AM Eastern Standard Time.



Steve Preston


The path of tomorrow’s occultation along with the circumstances. Credit: Steve Preston’s Asteroid Occultation website.
The maximum predicted length of the occultation for observers based along the centerline is just over 27 seconds. Note that 3 Juno also shines at magnitude +8.5, so both it and the star are binocular objects. The event will sweep across Winnipeg and Lake of the Woods straddling the U.S. Canadian border, just missing Duluth Minnesota before crossing Lake Superior and over Ottawa and Montreal and passing into northern Vermont and New Hampshire. Finally, the path crosses over Portland Maine, and heads out to sea over the Atlantic Ocean.

Don’t live along the path? Observers worldwide will still see a close pass of 3 Juno and the +7th magnitude star as both do their best to impersonate a close binary pair. If you’ve never crossed spotting 3 Juno off of your astro-“life list,” now is a good time to try.

The position of the target star HIP43357/SAO 117176 is:

Right Ascension: 8 Hours 49’ 54”

Declination: +2° 21’ 44”



Starry Night


A finder chart for 3 Juno and HIP43357. Stars are noted down to +10th magnitude. Created using Starry Night Education software.
Generally, the farther east you are along the track, the higher the pair will be above the horizon when the event occurs, and the better your observing prospects will be in terms of altitude or elevation. From Portland Maine — the last port of call for the shadow of 3 Juno on dry land — the pair will be 35 degrees above the horizon in the constellation of Hydra.



NOAA


The projected sky cover at the time of the occultation. Credit: NWS/NOAA.
As always, the success in observing any astronomical event is at the whim of the weather, which can be fickle in North America in November. As of 48 hours out from the occultation, weather prospects look dicey, with 70%-90% cloud cover along the track. But remember, you don’t necessarily need a fully clear sky to make a successful observation… just a clear view near the head of Hydra asterism. Remember the much anticipated occultation of Regulus by the asteroid 163 Erigone earlier this year? Alas, it went unrecorded due to pesky but pervasive cloud cover. Perhaps this week’s occultation will fall prey to the same, but it’s always worth a try. In asteroid occultations as in free throws, you miss 100% of the shots that you don’t take!



IOTA


The path of the occcultation across eastern North America. Credit: Google Earth/BREIT IDEAS observatory.
Why study asteroid occultations? Sure, it’s cool to see a star wink out as an asteroid passes in front of it, but there’s real science to be done as well. Expect the star involved in Thursday’s occultation to dip down about two magnitudes (six times) in brightness. The International Occultation Timing Association (IOTA) is always seeking careful measurements of asteroid occultations of bright stars. If enough observations are made along the track, a shape profile of the target asteroid emerges. And the possible discovery of an “asteroid moon” is not unheard of using this method, as the background star winks out multiple times.



UT-Juno Occultation


3 Juno as imaged by the 100″ Hooker telescope at the Mt. Wilson observatory at different wavelengths using adaptive optics. Credit: NASA/JPL/The Harvard Smithsonian Center for Astrophysics.
3 Juno was discovered crossing Cetus by astronomer Karl Harding on September 1st, 1804 from the Lilienthal Observatory in Germany. The 3rd asteroid discovered after 1 Ceres and 2 Pallas, 3 Juno ranks 5th in size at an estimated 290 kilometres in diameter. In the early 19th century, 3 Juno was also considered a planet along with these other early discoveries, until the ranks swelled to a point where the category of asteroid was introduced. A denizen of the asteroid belt, 3 Juno roams from 2 A.U.s from the Sun at perigee to 3.4 A.U.s at apogee, and can reach a maximum brightness of +7.4th magnitude as seen from the Earth. No space mission has ever been dispatched to study 3 Juno, although we will get a good look at its cousin 1 Ceres next April when NASA’s Dawn spacecraft enters orbit around the king of the asteroids.

3 Juno reaches opposition and its best observing position on January 29th, 2015.

3 Juno also has an interesting place in the history of asteroid occultations. The first ever predicted and successfully observed occultation of a star by an asteroid involved 3 Juno on February 19th, 1958. Another occultation involving the asteroid on December 11th, 1979 was even more widely observed. Only a handful of such events were caught prior to the 1990s, as it required ultra-precise computation and knowledge of positions and orbits. Today, dozens of asteroid occultations are predicted each month worldwide.

Observing an asteroid occultation can be challenging but rewarding. You can watch Thursday’s event with binoculars, but you’ll want to use a telescope to make a careful analysis. You can either run video during the event, or simply watch and call out when the star dims and brightens as you record audio. Precise timing and pinpointing your observing location via GPS is key, and human reaction time plays a factor as well. Be sure to locate the target star well beforehand. For precise time, you can run WWV radio in the background.

And finally, you also might see… nothing. Asteroid paths have a small amount of uncertainty to them, and although these negative observations aren’t as thrilling to watch, they’re important to the overall scientific effort.

Good luck, and let us know of your observational tales of anguish and achievement!



About 

David Dickinson is an Earth science teacher, freelance science writer, retired USAF veteran & backyard astronomer. He currently writes and ponders the universe from Tampa Bay, Florida.

“Spotters Guide” for Detecting Black Hole Collisions

“Spotters Guide” for Detecting Black Hole Collisions:



This artist's concept illustrates a supermassive black hole with millions to billions times the mass of our sun. Supermassive black holes are enormously dense objects buried at the hearts of galaxies. Image credit: NASA/JPL-Caltech


Black holes are a region in spacetime where intense gravity prevents anything, even light, from escaping. Credit: NASA/JPL-Caltech
When it comes to the many mysteries of the Universe, a special category is reserved for black holes. Since they are invisible to the naked eye, they remain visibly undetected, and scientists are forced to rely on “seeing” the effects their intense gravity has on nearby stars and gas clouds in order to study them.

That may be about to change, thanks to a team from Cardiff University. Here, researchers have achieved a breakthrough that could help scientists discover hundreds of black holes throughout the Universe.



Led by Dr. Mark Hannam from the School of Physics and Astronomy, the researchers have built a theoretical model which aims to predict all potential gravitational-wave signals that might be found by scientists working with the Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors.

These detectors, which act like microphones, are designed to search out remnants of black hole collisions. When they are switched on, the Cardiff team hope their research will act as a sort of “spotters guide” and help scientists pick up the faint ripples of collisions – known as gravitational waves – that took place millions of years ago.



X-ray/radio composite image of two supermassive black holes spiral towards each other near the center of a galaxy cluster named Abell 400. Credit: X-ray: NASA/CXC/AIfA/D.Hudson & T.Reiprich et al.; Radio: NRAO/VLA/NRL


X-ray/radio composite image of two supermassive black holes spiraling towards each other near the center of Abell 400 galaxy cluster. Credit: X-ray: NASA/CXC/AIfA/D.Hudson & T.Reiprich et al.; Radio: NRAO/VLA/NRL
Made up of postdoctoral researchers, PhD students, and collaborators from universities in Europe and the United States, the Cardiff team will work with scientists across the world as they attempt to unravel the origins of the Universe.

“The rapid spinning of black holes will cause the orbits to wobble, just like the last wobbles of a spinning top before it falls over,” Hannam said. “These wobbles can make the black holes trace out wild paths around each other, leading to extremely complicated gravitational-wave signals. Our model aims to predict this behavior and help scientists find the signals in the detector data.”

Already, the new model has been programmed into the computer codes that LIGO scientists all over the world are preparing to use to search for black-hole mergers when the detectors switch on.

Dr Hannam added: “Sometimes the orbits of these spinning black holes look completely tangled up, like a ball of string. But if you imagine whirling around with the black holes, then it all looks much clearer, and we can write down equations to describe what is happening. It’s like watching a kid on a high-speed spinning amusement park ride, apparently waving their hands around. From the side lines, it’s impossible to tell what they’re doing. But if you sit next to them, they might be sitting perfectly still, just giving you the thumbs up.”



Researchers crunched Einstein's theory of general relativity on the Columbia supercomputer at the NASA Ames Research Center to create a three-dimensional simulation of merging black holes. Image Credit: Henze, NASA


Researchers crunched Einstein’s theory of general relativity on the Columbia supercomputer at the NASA Ames Research Center to create a three-dimensional simulation of merging black holes. Credit: Henze, NASA
But of course, there’s still work to do: “So far we’ve only included these precession effects while the black holes spiral towards each other,” said Dr. Hannam. “We still need to work our exactly what the spins do when the black holes collide.”

For that they need to perform large computer simulations to solve Einstein’s equations for the moments before and after the collision. They’ll also need to produce many simulations to capture enough combinations of black-hole masses and spin directions to understand the overall behavior of these complicated systems.

In addition, time is somewhat limited for the Cardiff team. Once the detectors are switched on, it will only be a matter of time before the first gravitational wave-detections are made. The calculations that Dr. Hannam and his colleagues are producing will have to ready in time if they hope to make the most of them.

But Dr. Hannam is optimistic. “For years we were stumped on how to untangle the black-hole motion,” he said. “Now that we’ve solved that, we know what to do next.”

Further Reading: News Center – Cardiff U



About 

Author, freelance writer, educator, Taekwon-Do instructor, and loving hubby, son and Island boy!

Tuesday, November 18, 2014

Macro View Makes Dark Matter Look Even Stranger

Macro View Makes Dark Matter Look Even Stranger:



New research suggests that Dark Matter may exist in clumps distributed throughout our universe. Credit: Max-Planck Institute for Astrophysics


New research suggests that Dark Matter may exist in clumps distributed throughout our universe. Credit: Max-Planck Institute for Astrophysics
We know dark matter exists. We know this because without it and dark energy, our Universe would be missing 95.4% of its mass. What’s more, scientists would be hard pressed to explain what accounts for the gravitational effects they routinely see at work in the cosmos.

For decades, scientists have sought to prove its existence by smashing protons together in the Large Hadron Collider. Unfortunately, these efforts have not provided any concrete evidence.

Hence, it might be time to rethink dark matter. And physicists David M. Jacobs, Glenn D. Starkman, and Bryan Lynn of Case Western Reserve University have a theory that does just that, even if it does sound a bit strange.

In their new study, they argue that instead of dark matter consisting of elementary particles that are invisible and do not emit or absorb light and electromagnetic radiation, it takes the form of chunks of matter that vary widely in terms of mass and size.

As it stands, there are many leading candidates for what dark matter could be, which range from Weakly-Interacting Massive Particles (aka WIMPs) to axions. These candidates are attractive, particularly WIMPs, because the existence of such particles might help confirm supersymmetry theory – which in turn could help lead to a working Theory of Everything (ToE).



According to supersymmetry, dark-matter particles known as neutralinos (which are often called WIMPs) annihilate each other, creating a cascade of particles and radiation that includes medium-energy gamma rays. If neutralinos exist, the LAT might see the gamma rays associated with their demise. Credit: Sky & Telescope / Gregg Dinderman.


According to supersymmetry, dark-matter particles known as neutralinos (aka WIMPs) annihilate each other, creating a cascade of particles and radiation. Credit: Sky & Telescope / Gregg Dinderman.
But so far, no evidence has been obtained that definitively proves the existence of either. Beyond being necessary in order for General Relativity to work, this invisible mass seems content to remain invisible to detection.

According to Jacobs, Starkman, and Lynn, this could indicate that dark matter exists within the realm of normal matter. In particular, they consider the possibility that dark matter consists of macroscopic objects – which they dub “Macros” – that can be characterized in units of grams and square centimeters respectively.

Macros are not only significantly larger than WIMPS and axions, but could potentially be assembled out of particles in the Standard Model of particle physics – such as quarks and leptons from the early universe – instead of requiring new physics to explain their existence. WIMPS and axions remain possible candidates for dark matter, but Jacobs and Starkman argue that there’s a reason to search elsewhere.

“The possibility that dark matter could be macroscopic and even emerge from the Standard Model is an old but exciting one,” Starkman told Universe Today, via email. “It is the most economical possibility, and in the face of our failure so far to find dark matter candidates in our dark matter detectors, or to make them in our accelerators, it is one that deserves our renewed attention.”

After eliminating most ordinary matter – including failed Jupiters, white dwarfs, neutron stars, stellar black holes, the black holes in centers of galaxies, and neutrinos with a lot of mass – as possible candidates, physicists turned their focus on the exotics.



Particle Collider


Ongoing experiments at the Large Hadron Collider have so far failed to produce evidence of WIMPs. Credit: CERN/LHC/GridPP
Nevertheless, matter that was somewhere in between ordinary and exotic – relatives of neutron stars or large nuclei – was left on the table, Starkman said. “We say relatives because they probably have a considerable admixture of strange quarks, which are made in accelerators and ordinarily have extremely short lives,” he said.

Although strange quarks are highly unstable, Starkman points out that neutrons are also highly unstable. But in helium, bound with stable protons, neutrons remain stable.

“That opens the possibility that stable strange nuclear matter was made in the early Universe and dark matter is nothing more than chunks of strange nuclear matter or other bound states of quarks, or of baryons, which are themselves made of quarks,” said Starkman.

Such dark matter would fit the Standard Model.

This is perhaps the most appealing aspect of the Macros theory: the notion that dark matter, which our cosmological model of the Universe depends upon, can be proven without the need for additional particles.

Still, the idea that the universe is filled with a chunky, invisible mass rather than countless invisible particles does make the universe seem a bit stranger, doesn’t it?

Further Reading: Case Western



About 

Author, freelance writer, educator, Taekwon-Do instructor, and loving hubby, son and Island boy!