Posted on by Ken Kremer

Dawn Closing in on Asteroid Vesta as Views Exceed Hubble

Hubble and Dawn Views of Vesta. These views of the protoplanet Vesta were obtained by NASA's Dawn spacecraft and NASA's Hubble Space Telescope. The image from Dawn, on the left, is a little more than twice as sharp as the image from Hubble, on the right. The image from Hubble, which is in orbit around the Earth, was obtained on May 14, 2007, when Vesta was 109 million miles (176 million kilometers) away from Earth. Dawn's image was taken on June 20, 2011, when Dawn was about 117,000 miles (189,000 kilometers) away from Vesta. The framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI and NASA/ESA/STScI/UMd

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A new world in our Solar System is about to be unveiled for the first time – the mysterious protoplanet Vesta, which is the second most massive object in the main Asteroid Belt between Mars and Jupiter.

NASA’s Dawn Asteroid orbiter has entered its final approach phase to Vesta and for the first time is snapping images that finally exceed those taken several years ago by the iconic Hubble Space Telescope.

“The Dawn science campaign at Vesta will unveil a mysterious world, an object that can tell us much about the earliest formation of the planets and the solar system,” said Jim Adams, Deputy Director, Planetary Science Directorate at NASA HQ at a briefing for reporters.

Vesta holds a record of the earliest history of the solar system. The protoplanet failed to form into a full planet due to its close proximity to Jupiter.

Check out this amazing NASA approach video showing Vesta growing in Dawn’s eyes. The compilation of navigation images from Dawn’s framing camera spans about seven weeks from May 3 to June 20 was released at the NASA press briefing by the Dawn science team.

Dawn’s Approach to Vesta – Video

Best View from Hubble – Video

Be sure to notice that Vesta’s south pole is missing due to a cataclysmic event eons ago that created a massive impact crater – soon to be unveiled in astounding clarity. Some of that colossal debris sped toward Earth and survived the terror of atmospheric entry. Planetary Scientists believe that about 5% of all known meteorites originated from Vesta, based on spectral evidence.

After a journey of four years and 1.7 billion miles, NASA’s revolutionary Dawn spacecraft thrusting via exotic ion propulsion is now less than 95,000 miles distant from Vesta, shaping its path through space to match the asteroid.

The internationally funded probe should be captured into orbit on July 16 at an initial altitude of 9,900 miles when Vesta is some 117 million miles from Earth.

After adjustments to lower Dawn to an initial reconnaissance orbit of approximately 1,700 miles, the science campaign is set to kick off in August with the collection of global color images and spectral data including compositional data in different wavelengths of reflected light.

Dawn Approaching Vesta
Dawn obtained this image on June 20, 2011. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI and NASA/ESA/STScI/UMd

Dawn will spend a year investigating Vesta. It will probe the protoplanet using its three onboard science instruments – provided by Germany, Italy and the US – and provide researchers with the first bird’s eye images, global maps and detailed scientific measurements to elucidate the chemical composition and internal structure of a giant asteroid.

“Navigation images from Dawn’s framing camera have given us intriguing hints of Vesta, but we’re looking forward to the heart of Vesta operations, when we begin officially collecting science data,” said Christopher Russell, Dawn principal investigator, at the University of California, Los Angeles (UCLA). “We can’t wait for Dawn to peel back the layers of time and reveal the early history of our solar system.”

Because Dawn is now so close to Vesta, the frequency of imaging will be increased to twice a week to achieve the required navigational accuracy to successfully enter orbit., according to Marc Rayman, Dawn Chief Engineer at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

“By the beginning of August, it will see Vesta with more than 100 times the clarity that Hubble could ever obtain,” says Rayman.

Vesta in Spectrometer View
On June 8, 2011, the visible and infrared mapping spectrometer aboard NASA's Dawn spacecraft captured the instrument's first images of Vesta that are larger than a few pixels, from a distance of about 218,000 miles (351,000 kilometers). The image was taken for calibration purposes. An image obtained in the visible part of the light spectrum appears on the left. An image obtained in the infrared spectrum, at around 3 microns in wavelength, appears on the right. The spatial resolution of this image is about 60 miles (90 kilometers) per pixel. Credit: NASA/JPL-Caltech/UCLA/ASI/INAF

Dawn will gradually edge down closer to altitudes of 420 miles and 120 miles to obtain ever higher resolution orbital images and spectal data before spiraling back out and eventually setting sail for Ceres, the largest asteroid of them all.

Dawn will be the first spacecraft to orbit two celestial bodies, only made possible via the ion propulsion system. With a wingspan of 65 feet, it’s the largest planetary mission NASA has ever launched.

“We’ve packed our year at Vesta chock-full of science observations to help us unravel the mysteries of Vesta,” said Carol Raymond, Dawn’s deputy principal investigator at JPL.

“This is an unprecedented opportunity to spend a year at a body that we know almost nothing about,” added Raymond. “We are very interested in the south pole because the impact exposed the deep interior of Vesta. We’ll be able to look at features down to tens of meters so we can decipher the geologic history of Vesta.”

Possible Piece of Vesta
Scientists believe a large number of the meteorites that are found on Earth originate from the protoplanet Vesta. A cataclysmic impact at the south pole of Vesta, the second most massive object in the main asteroid belt, created an enormous crater and excavated a great deal of debris. Some of that debris ended up as other asteroids and some of it likely ended up on Earth. Image Credit: NASA/JPL-Caltech
Dawn Trajectory and Current Location on June 29, 2011. Credt: NASA/JPL
Dawn launch on September 27, 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer

Read my prior feature about Dawn here

Posted on by Ken Kremer

NASA Sets July 8 for Mandatory Space Shuttle Grand Finale

NASA officially set July 8 to launch Space Shuttle Atlantis on the Grand Finale of the shuttle program. This photo shows Atlantis at Launch Pad 39A prior to installation of the cargo into the payload bay. Blastoff of the STS-135 mission is scheduled for 11:26 a.m. EDT from the Kennedy Space Center in Florida. Credit: Ken Kremer

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NASA Shuttle managers met today (28 June) and officially set July 8 as the launch date for the Grand Finale of the shuttle program by Space Shuttle Atlantis. And the NASA officials also emphasized that the STS-135 mission is absolutely crucial to the future well being and functioning of the International Space Station (ISS).

“This flight is incredibly important,” said Bill Gerstenmaier, NASA associate administrator for space operations. “The cargo that is coming up on this flight is really mandatory for space station. This mission is critical from a resupply standpoint. We will stay on orbit in case of some small orbiter failures.”

Atlantis’ primary goal is to dock with the million pound orbiting outpost and deliver the “Raffaello” logistics module. Raffaello is packed to the gills with some 5 tons of critical spare parts, food, water, provisions and science equipment that will keep the station stocked and the crew fed for a year. About one third of the cargo is food.

The STS 135 mission will buy invaluable time to keep the station running and science experiments continuing full tilt after the shuttles are retired and until replacement cargo vehicles are brought online.

STS-135 crew meets with journalists at base of Launch Pad 39A, Kennedy Space Center. From left; Mission Specialists Rex Walheim and Sandy Magnus; Pilot Doug Hurley and Commander Chris Ferguson. Credit: Ken Kremer

NASA hopes that commercial providers – SpaceX and Orbital Sciences – will soon pick up the slack and fill the supply void created by prematurely shutting down the shuttles now, before the replacement vehicles are functioning and proven. If the private company’s spacecraft are further delayed, then the ISS crew size may have to be reduced from 6 to 3 and station science operations could be significantly curtailed.

NASA announced the unanimous “GO” for the July 8 liftoff following a day long Flight Readiness Review at the Kennedy Space Center involving senior shuttle managers from the NASA and contractor teams.

NASA managers announced “GO” for launch of Atlantis on July 8 at a briefing for reporters at KSC. From left: Bill Gerstenmaier, NASA associate administrator for space operations, Mike Moses, Space Shuttle Program launch integration manager, Mike Leinbach, shuttle launch director. Credit: Chase Clark

“We had a very thorough review,” said Gerstenmaier. Shuttle managers reviewed the shuttle and launch pad systems, the risks associated with the flight as well as the payloads tucked inside the orbiter and an assortment of technical issues and problems that cropped up during the pre-launch processing.

The STS-135 crew comprises of just four astronauts, all veterans, led by Shuttle Commander Ferguson who is joined by Pilot Doug Hurley, and Mission Specialists Sandy Magnus and Rex Walheim. They are scheduled to fly back to Kennedy on Independence Day, Monday, July 4, for the final days of launch preparations.

Since there is no back up rescue shuttle, the shuttle astronauts would have to return to Earth aboard Russian Soyuz capsules in the event of an on orbit emergency.

“We’re really looking forward to achieving this mission, putting station where it needs to be and finishing strong with the shuttle program here with STS-135,” said Mike Moses, Space Shuttle Program launch integration manager.

Moses added that NASA very much wants to extend the planned 12 day flight by one more day to give the crew more time to transfer cargo back and forth between Raffaello and the station.

NASA especially wants to fully load Raffaello for the return trip with experiment samples and voluminous no longer needed items of trash to give the station crew additional work and storage space. The extension depends on consumables use and will be decided once on orbit. Without the shuttle, down mass capability will be severely limited until the private providers are ready.

Technicians at the pad worked successfully to swap out a faulty shuttle engine valve and take X-rays of reinforcing joints on the External Tank after the recent tanking test, thus enabling NASA to approve the July 8 launch date.

“Atlantis is in great shape out at the pad,” said Mike Leinbach, shuttle launch director. “Team Atlantis is feeling good about the flow and the launch countdown and hope we’ll be able to get her off the ground on Friday the 8th as scheduled.”

“We expect between 500,000 and 750,000 visitors for the launch,” added Leinbach. “We have three launch attempts available on July 8, 9 and 10.”

The countdown clocks will start ticking backwards at 1 p.m. on July 5. STS-135 is the 135th and last shuttle mission.

This will be Atlantis’ 33rd flight and the 37th overall to the station.

Atlantis will be the last of NASA’s three shuttle orbiters to be retired.

Side view of Atlantis at Launch Pad 39A during pre-launch processing on June 28. Credit: Chase Clark

Read my prior features about the Final Shuttle mission, STS-135, here:
Final Shuttle Voyagers Conduct Countdown Practice at Florida Launch Pad
Final Payload for Final Shuttle Flight Delivered to the Launch Pad
Last Ever Shuttle Journeys out to the Launch Pad; Photo Gallery
Atlantis Goes Vertical for the Last Time
Atlantis Rolls to Vehicle Assembly Building with Final Space Shuttle Crew for July 8 Blastoff

Posted on by Ken Kremer

Final Shuttle Voyagers Conduct Countdown Practice at Florida Launch Pad

STS-135 crew at TCDT Q&A session with journalists at base of Launch Pad 39A, Kennedy Space Center. From left; Mission Specialists Rex Walheim and Sandy Magnus; Pilot Doug Hurley and Commander Chris Ferguson

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KENNEDY SPACE CENTER – The “Final Four” shuttle astronauts who will ever voyage to Earth orbit aboard a NASA Space Shuttle Orbiter jetted into the Kennedy Space Center (KSC) this week for their final simulated countdown training at the seaside Florida Launch Pad.

The all veteran crew for the STS-135 mission arrived at Kennedy’s Shuttle Landing Facility (SLF) on twin T-38 jets for four days of comprehensive flight training for what’s known as the Terminal Countdown Demonstration Test (TCDT). Along with all other shuttle flight related activities, it’s the very last time this training will ever occur.

The TCDT is part of the ritual of training for all shuttle crews that takes place in the last few weeks preceding a liftoff and that concludes with a full countdown dress rehearsal from inside Atlantis at the launch pad.

The last ever shuttle crew jets into KSC for TCDT training at KSC aboard T-38 jets. From left; Sandy Magnus, Doug Hurley, Commander Chris Ferguson and Rex Walheim. Credit: Ken Kremer

Chris Ferguson is leading the STS-135 mission and he will be recorded in history as the final Space Shuttle Commander. This will be Ferguson’s third shuttle flight and second one as Commander. Also aboard are Pilot Doug Hurley and Mission Specialists Sandy Magnus and Rex Walheim.

The quartet of space flyers are due to blast off aboard Space Shuttle Atlantis on July 8 at 11:26 a.m. EDT for the “Grand Finale” of NASA’s thirty year old Space Shuttle Program. If all goes according to plan the end of the Shuttle Era is less than 1 month away.

It’s a bittersweet moment for everyone working on the shuttle program. Proud to be part of a magnificent adventure with the most complicated machine ever built by humans, but simultaneously sad that the program is ending well before its true flight time is up and with no concrete timetable to replace the trio of majestic spaceships.

“We are incredibly proud to represent this, the final flight,” said STS-135 Commander Chris Ferguson after touchdown to dozens and dozens of journalists gathered at the shuttle landing strip to greet the astronauts.

“I speak on behalf of the crew, everyone in the astronaut office, and I’m sure everybody here at KSC in saying that we are just trying to savor the moment,” Ferguson added. “As our children and our children’s children ask us, we want to be able to say, ‘We remember when there was a space shuttle.”

The first order of business for Ferguson and Hurley was to practice shuttle landings in the Shuttle Training Aircraft (STA), which is a modified Gulfstream II jet.

During the TCDT period, the crew engaged in mission briefings at the Launch Control Center which is the brain of shuttle launch operations, payload familiarization and training at the Space Station Processing Facility, fire suppression training, range safety and security briefings and emergency escape training in an M113 armored personnel carrier near Launch Pad 39A. Read more in my upcoming features.

On the last day of TCDT, the astronauts donned their orange launch and entry suits, journeyed to the pad in the Astrovan and were strapped to their assigned seated inside the orbiter exactly as will occur on launch day for a full dress rehearsal of the launch countdown.

STS-135 Crew at TCDT pad emengency training at Pad 39A. From left are Commander Chris Ferguson, Pilot Doug Hurley, Mission Specialists Sandy Magnus and Rex Walheim. Credit: NASA/Kim Shiflett

The crew also met with over 100 reporters for a Q & A session at the base of Launch Pad 39A which was back dropped by a thrilling view of Shuttle Atlantis atop the Mobile Launch Platform and the gigantic Flame Duct which directs the rocket exhaust way from the shuttle stack during launch.

“We’re very honored to be in this position,” Ferguson said to reporters at the foot of the pad. “There are many people who could be here. When the dice fell our names were facing up. We consider ourselves fortunate and lucky.”

“I think each of us feels a little extra burden to make sure we put on the best possible face forward for the last go around of this. The crew’s very prepared and we’re going to do a fantastic job.”

“I don’t think that the full magnitude of the moment will really hit us until the wheels have stopped on the runway,” said Ferguson, reflecting on the significance of the grand finale of all shuttle missions. “I’m not sure words will really be able to capture for the crew and for the entire shuttle workforce just how much the shuttle program has meant to us for the last 30 years.”

“TDCT is very comprehensive, hands on and invaluable training at the place you’re going to do it,” said Hurley. “Everything is a just a little bit different when you are in the real vehicle so this is a great way to get you ready for launch day – when it counts!”

Tucked inside Atlantis cargo bay is the Italian- built “Raffaello” logistics module, the primary payload. Raffaello is loaded full with some five tons of critical spare parts, crew supplies and science experiments that will be delivered to the International Space Station (ISS) during the 12 day flight.

The secondary payload is the Robotic Refueling Mission (RRM) which will demonstrate tools and techniques to refuel satellites in orbit.

The STS-135 crew arrive at KSC aboard a wave of T-38 jets for countdown, payload and emergency training. Credit: Ken Kremer

“Sandy Magnus is our ‘transfer czar’ in charge of emptying and filling Raffaello,” said Ferguson. Magnus is an ideal choice for the mission since she lived for months aboard the orbiting outpost and is familiar with its nook and crannies.

“We feel very honored to be on this flight and are very focused to perform it well,” said Magnus. “We are just the tip of the iceberg of a huge group of people who plan and get the hardware ready and prepare all our procedures.”

“I often think about how we will launch from the exact same launch pad that Apollo 11 launched at to go to the moon. It gives you goose bumps,” said Walheim.

Media with STS-135 astronuats at TCDT Q&A session at Launch Pad 39A. Credit: Ken Kremer

Watch the TDCT Launch Pad press conference here:

Read my prior features about the Final Shuttle mission, STS-135, here:
Final Payload for Final Shuttle Flight Delivered to the Launch Pad
Last Ever Shuttle Journeys out to the Launch Pad; Photo Gallery
Atlantis Goes Vertical for the Last Time
Atlantis Rolls to Vehicle Assembly Building with Final Space Shuttle Crew for July 8 Blastoff

Posted on by Ken Kremer

Dramatic New NASA Animation Depicts Next Mars Rover in Action

NASA's Mars Science Laboratory Curiosity rover. Curiosity is a mobile robot for investigating Mars' past or present ability to sustain microbial life. Curiosity is being tested in preparation for launch in the fall of 2011. The mast, or rover's "head," rises to about 2.1 meters (6.9 feet) above ground level, about as tall as a basketball player. This mast supports two remote-sensing instruments: the Mast Camera, or "eyes," for stereo color viewing of surrounding terrain and material collected by the arm; and, the ChemCam instrument, which is a laser that vaporizes material from rocks up to about 9 meters (30 feet) away and determines what elements the rocks are made of. Credit: NASA/JPL-Caltech. New NASA High Resolution Curiosity Animations below

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NASA’s next Mars rover, the Curiosity Mars Science Laboratory, will soon embark on a quantum leap in humankind’s scientific exploration of the Martian surface -the most Earthlike planet in our Solar System.

To get a birds eye understanding of Curiosity’s magnificent capabilities, check out the dramatic new high resolution animation below which depicts NASA’s next Mars rover traversing tantalizing terrain for clues to whether Martian microbial life may have existed, evolved and been sustained in past or present times.


The new action packed animation is 11 minutes in length. It depicts sequences starting with Earth departure, smashing through the Martian atmosphere, the nail biting terror of the never before used rocket-backpack sky crane landing system and then progressing through the assorted science instrument capabilities that Curiosity will bring to bear during its minimum two year expedition across hitherto unseen and unexplored Martian landscapes, mountains and craters.

Curiosity is equipped with 10 science instruments. The three meter long robot is five times the weight of any previous Mars rover.

Those who closely follow the adventures of NASA’s Spirit and Opportunity rovers, like myself, will quickly recognize several of the panoramic scenes which have been included to give a realistic feeling of vistas to expect from the car sized Curiosity rover.

Here is a shorter 4 minute animation with expert narration


Along the way you’ll experience Curiosity zapping rocks with a laser, deftly maneuvering her robotic arm and camera mast and retrieving and analyzing Martian soil samples.

“It is a treat for the 2,000 or more people who have worked on the Mars Science Laboratory during the past eight years to watch these action scenes of the hardware the project has developed and assembled,” said Mars Science Laboratory Project Manager Pete Theisinger at NASA’s Jet Propulsion Laboratory, Pasadena, Calif, in a NASA statement. “The animation also provides an exciting view of this mission for any fan of adventure and exploration.”

Curiosity - The Next Mars Rover analyzes Martian rocks
Curiosity rover examines a rock on Mars with a set of tools at the end of the rover's arm, which extends about 2 meters (7 feet). Two instruments on the arm can study rocks up close. Also, a drill can collect sample material from inside of rocks and a scoop can pick up samples of soil. The arm can sieve the samples and deliver fine powder to instruments inside the rover for thorough analysis. Credit: NASA/JPL-Caltech

Curiosity was flown this week from her birthplace at NASA’s Jet Propulsion Laboratory in California to her future launch site in Florida aboard a C-17 military cargo transport aircraft.

She arrived at the Shuttle Landing Facility (SLF) at the Kennedy Space Center on June 22. The SLF is the same landing strip where I watched the STS-135 crew arrive for NASA’s final shuttle mission just days earlier days for their final launch countdown training.

NASA has scheduled Curiosity to blast off for the red planet on Nov. 25, 2011 from Cape Canaveral Air Force Station aboard an Atlas V rocket. Curiosity will touchdown in August 2012 at a landing site that will be announced soon by Ed Weiler, NASA Associate Administrator for the Science Mission Directorate in Washington, D.C.

Curiosity rover traverses new Martian terrain in search of habitats for microbial life. Credit: NASA/JPL-Caltech

Read my prior features about Curiosity
Packing a Mars Rover for the Trip to Florida; Time Lapse Video
Test Roving NASA’s Curiosity on Earth
Curiosity Mars Rover Almost Complete
Curiosity Rover Testing in Harsh Mars-like Environment

Posted on by Tammy Plotner

Genesis Sheds Light On Sun And Solar System Formation

Artist Concept of Genesis Courtesy of JPL/NASA

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For 886 days between 2001 and 2004, a tiny spacecraft named Genesis sat parked at Lagrange Point L1 quietly collecting solar wind samples. On Sept. 8, 2004, the spacecraft released a sample return capsule which bashed its way onto the Utah desert carrying its little payload. Despite the disastrous crash, solar-wind ions were found buried beneath the surface of the collectors and what they have to tell us about the possible formation of our solar system is pretty amazing.

In March 2005 the international scientific community was given the collectors to study – and one of their prime targets was the evolution of our solar system. How could these tiny particles give us clues as to our origin? According the bulk of evidence, it is surmised the outer layer of the Sun hasn’t changed in several billion years. If we are to agree this is a good basis for modeling our solar nebula, we could begin to understand the chemical processes which formed our solar system. For most rock-forming elements, there appears to be little fractionation of either elements or isotopes between the sun and the solar wind. Or is there?

“The implication is that we did not form out of the same solar nebula materials that created the sun — just how and why remains to be discovered,” said Kevin McKeegan, a Genesis co-investigator from the University of California, Los Angeles and the lead author of one of two Science papers published this week.

Using the deposits found on the collector plates, scientists found a higher rate of common oxygen isotopes and a lowered rate of rare ones – different from Earth’s ratios. The same held true of nitrogen composition.

“These findings show that all solar system objects, including the terrestrial planets, meteorites and comets, are anomalous compared to the initial composition of the nebula from which the solar system formed,” said Bernard Marty, a Genesis co-investigator from Centre de Recherches Petrographiques et Geochimiques in Nancy, France and the lead author of the second new Science paper. “Understanding the cause of such a heterogeneity will impact our view on the formation of the solar system.”

While more studies are in the making, this new evidence provides vital information which may correct how we initially perceived our beginnings. While these elements are the most copious of all, even slight differences make them as distinctive as salt and pepper.

“The sun houses more than 99 percent of the material currently in our solar system so it’s a good idea to get to know it better,” said Genesis principal investigator Don Burnett of the California Institute of Technology in Pasadena, Calif. “While it was more challenging than expected we have answered some important questions, and like all successful missions, generated plenty more.”

Original Story Source: JPL Genesis Mission News.

Posted on by Ken Kremer

Packing a Mars Rover for the Trip to Florida

Check out this way cool time-lapse movie of NASA’s Curiosity Mars rover as its being packed up for her trip to Florida.

The video covers a 4 day period from June 13 to 17 and is condensed to just 1 minute. Watch the JPL engineers and technicians prepare Curiosity and the descent stage for shipping to the Kennedy Space Center in Florida and place it inside a large protective shipping container. Continue reading “Packing a Mars Rover for the Trip to Florida”

Posted on by Tammy Plotner

White Dwarf Stars Predict Our Solar System’s Demise

A Hubble Space Telescope color image of a small portion of the cluster only 0.63 light-years across reveals eight white dwarf stars (inside blue circles) among the cluster's much brighter population of yellow sun-like stars and cooler red dwarf stars. (Credit: Harvey Richer (University of British Columbia, Vancouver, Canada) and NASA)

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With no more volume than could be contained within a teaspoon, the material that makes up a white dwarf star weighs tons. Smaller than the diameter of Earth, and a direct family member of stars like our own Sol, these stellar gnomes could predict our eventual fate.

Using data from the Hubble Space Telescope, Nathan Dickinson, a postgraduate student in the University’s Department of Physics and Astronomy, is hard at work analyzing chemical compositions of white dwarf stars for his PhD. Unlike many students interested in “heavy metal”, Dickinson is more interested in “heavy elements”. The older, more cool models could contain elements such as oxygen, nitrogen, silicon… while the hot youngsters show heavy elements like calcium and magnesium. These weighty basics occur at extreme heat and sometimes, even to excess. The cremation generation?

“Understanding whether the extra material in hot white dwarfs comes from torn up planets is important,” emphasizes Dickinson. “It can give us an idea of how these ancient planetary systems evolve as the star ages, so we get a fuller picture of how solar systems die. However, they sometimes exhibit more of this material than is expected, which raises the question of whether this extra material also came from planets or whether it originated elsewhere, perhaps in clouds around the star.”

Past research has shown that anywhere from 1 to 3% of white dwarf stars can be contaminated by an influx of materials from closely orbiting dust clouds. What makes up these clouds? It could be rocky debris like asteroids. Held within the Roche Limit, these planetoids are mulched by gravitational tides – just like Saturn’s ring system.

“Working at the forefront of this scientific area is extremely exciting,” says Dickinson. “I find being one of a relatively small community of people in the world to work on this particular area amazing. This work is helping to shape our understanding of how most stars end their lives, how solar systems die, how the environment around these ancient stars behaves and what will ultimately happen to the vast majority of stars in the galaxy.”

And really close to home…

Original Story Source: Science Daily.

Posted on by Ken Kremer

MESSENGER Unveiling Mercurys Hidden Secrets

Spectacular view of the Degas crater from MESSENGER in Mercury orbit. This high-resolution view of Degas crater was obtained as a targeted observation (90 m/pixel). Impact melt coats its floor, and as the melt cooled and shrank, it formed the cracks observed across the crater. For context, Mariner 10’s view of Degas is shown at left. Degas is 52 km in diameter and is centered at 37.1° N, 232.8° E. Credit: NASA/The Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

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NASA’s MESSENGER probe to Mercury, the scorched, innermost planet of our solar system, is sending back so much startling and revolutionary data and crystal clear images that the results are forcing scientists to toss out previously cherished theories and formulate new ones even as the results continues to pour in. And the mission has barely begun to explore Mercury’s inner secrets, exterior surface and atmospheric environment.

MESSENGER became the first spacecraft ever to orbit planet Mercury on March 18, 2011 and has just completed the first quarter of its planned one year long mission – that’s the equivalent of one Mercury year.

MESSENGER has collected a treasure trove of new data from the seven instruments onboard yielding a scientific bonanza; these include extensive global imagery, measurements of the planet’s surface chemical composition, topographic evidence for significant amounts of water ice, magnetic field and interactions with the solar wind, reported the science team at a press conference at NASA Headquarters.

Schematic illustration of the operation of MESSENGER's X-ray Spectrometer (XRS). When X-rays emitted from the Sun’s corona strike the planet, they can induce X-ray fluorescence from atoms at the surface. Detection of these fluorescent X-rays by the XRS allows determination of the surface chemical composition. Credit: NASA/The Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

“We are delighted to share the findings of the first 25% of our year long mission,” said MESSENGER principal investigator Sean Solomon of the Carnegie Institution of Washington at a press briefing for reporters. “We receive new data back almost every day.”

“MESSENGER has snapped over 20,000 images to date,” said Solomon, at up to 10 meters per pixel. The probe has also taken over two million laser-ranging topographic observations, discovered vast volcanic plains, measured the abundances of many key elements and confirmed that bursts of energetic particles in Mercury’s magnetosphere result from the interaction of the planets magnetic field with the solar wind.

“We are assembling a global overview of the nature and workings of Mercury for the first time.”

“We had many ideas about Mercury that were incomplete or ill-formed, from earlier flyby data,” explained Solomon. “Many of our older theories are being cast aside into the dust bin as new observations from new orbital data lead to new insights. Our primary mission has another three Mercury years to run, and we can expect more surprises as our solar system’s innermost planet reveals its long-held secrets.”

Magnetic field lines differ at Mercury's north and south poles As a result of the north-south asymmetry in Mercury's internal magnetic field, the geometry of magnetic field lines is different in Mercury's north and south polar regions. In particular, the magnetic "polar cap" where field lines are open to the interplanetary medium is much larger near the south pole. This geometry implies that the south polar region is much more exposed than in the north to charged particles heated and accelerated by solar wind–magnetosphere interactions. The impact of those charged particles onto Mercury's surface contributes both to the generation of the planet's tenuous atmosphere and to the "space weathering" of surface materials, both of which should have a north-south asymmetry given the different magnetic field configurations at the two poles. Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

NASA’s Mariner 10 was the only previous robotic probe to explore Mercury, during three flyby’s back in the mid-1970’s early in the space age.

MESSENGER was launched in 2004 and the mission goal is to produce the first global scientific observations of Mercury and piece together the puzzle of how Mercury fits in with the origin and evolution of our solar system.

There was very little prior imaging coverage of Mercury’s northern polar region.

“We’ve now filled in many of the gaps,” said Messenger scientist Brett Denevi of Johns Hopkins University’s Applied Physics Laboratory (APL). “We now see large smooth plains that are thought to be volcanic in origin.”

“Now we’re seeing for the first time their full extent, which is around 4 million square kilometers (1.54 million square miles). That’s about half the size of the continental United States.”

MESSENGER is currently filling in coverage of Mercury’s north polar region, which was seen only partially during the Mariner 10 and MESSENGER flybys. Flyby images indicated that smooth plains were likely important in Mercury’s northernmost regions. MESSENGER's orbital images show that the plains are among the largest expanses of volcanic deposits on Mercury, with thicknesses of several kilometers in many places. The estimated extent of these plains is outlined in yellow. This mosaic is a combination of flyby and orbital coverage in a polar stereographic projection showing latitudes from 50° to 90° N. The longitude at the 6 o'clock position is 0°. Credit: NASA/The Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

“We see all kinds of evidence for volcanism and tectonic deformation of the plains from orbit where we can look straight down,” added Denevi. “In the new images we see ghost craters from pre-existing impact craters that were later covered over by lava.’

Color images of the whole planet – with a resolution of about 1 kilometer per pixel – tell the researchers about the chemical composition and rock types on Mercury’s surface.

“We don’t know the composition yet.”

“We are very excited to study these huge volcanic deposits near the north pole with the implications for the evolution of Mercury’s crust and how it formed,” said Denevi.

“Targeted new high resolution imaging is helping us see landforms unlike anything we’ve seen before on Mercury or the moon.”

MESSENGER’s orbital images have been overlaid on an image from the second flyby shown in Image 1.2a. Even for previously imaged portions of the surface, orbital observations reveal a new level of detail. This region is part of the extensive northern plains, and evidence for a volcanic origin can now be seen. Several examples of “ghost” craters, preexisting craters that were buried by the emplacement of the plains, are seen near the center of the mosaic. Credit: NASA/The Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Determining whether Mercury harbors caches of polar water ice is another one of the many questions the MESSENGER science team hopes to answer.

Two decades ago, Earth-based radar images showed deposits thought to consist of water ice near Mercury’s north and south poles. Researchers postulated a theory that these icy deposits are preserved on the cold, permanently shadowed floors of high-latitude impact craters, similar to those on Earth’s moon.

Early results from topographic measurements are promising.

“The very first scientific test of that hypothesis using Messenger data from orbit has passed with flying colors.”

“The area of possible polar water ice is quite a bit larger than on the moon,” said Solomon. “Its probably meters or more in depth based on radar measurements.”

“And we may have the irony that the planet closest to the sun may have more water ice at its poles than even our own moon.”

“Stay tuned. As this mission evolves, we will be relying on the geochemical and remote sensing instruments which take time to collect observations. The neutron and gamma ray spectrometers have the ability to tell us the identity of these icy materials,” said Solomon.

The same scene as that in Image 1.3a is shown after the application of a statistical method that highlights differences among the eight color filters, making variations in color and composition easier to discern. Credit: NASA/The Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
This topographic contour map was constructed from the several MLA profiles (lines of white circles) that pass through and near the crater circled in Image 3.4. The color scale at right is in km, and north is at the 4 o’clock position. Calculations show that the topography of the crater is consistent with the prediction that the southernmost portion of the crater floor is in permanent shadow. Credit: NASA/The Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
A cross-section of Mercury’s magnetosphere (in the noon-midnight plane, i.e., the plane containing the planet-Sun line and Mercury’s spin axis) provides context for the energetic electron events observed to date with the MESSENGER XRS and GRS high-purity germanium (HpGe) detectors. The Sun is toward the right; dark yellow lines indicate representative magnetic field lines. Blue and green lines trace the regions along MESSENGER's orbit from April 2 to April 10 during which energetic electrons were detected and MESSENGER's orbit was within ± 5° of the noon-midnight plane. The presence of events on the dayside, their lack in the southern hemisphere, and their frequency of occurrence at middle northern latitudes over all longitudes point to a more complex picture of magnetospheric activity than found at Earth. Credit: NASA/The Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Posted on by Ken Kremer

Final Payload for Final Shuttle Flight Delivered to the Launch Pad

Space Shuttle Atlantis and cargo canister at Launch Pad 39A for Final Shuttle Flight. This view shows the delivery of the cargo canister – white rectangular box - with the payloads for the last shuttle mission; STS-135. The canister has been hoisted up the Rotating Service Structure, at right, for installation into the orbiters payload bay. Credit: Ken Kremer

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KENNEDY SPACE CENTER – The cargo canister for NASA’s final space shuttle mission was delivered to the sea-side launch pad at the Kennedy Space Center (KSC) in Florida and hoisted up the pads massive launch pad gantry early Friday (June 17).

NASA is targeting a July 8 blastoff of the STS-135 mission with Space Shuttle Atlantis and the last cargo a shuttle will ever haul to space. The 60 foot long cargo canister is the size of a shuttle payload bay.

The STS-135 mission is the very final flight of the three decade long Space Shuttle Era and is slated for liftoff at 11:26 a.m. EDT from Launch Pad 39A. The flight is scheduled to last 12 days and will be NASA’s 36th and last shuttle mission bound for the International Space Station (ISS).

Atlantis will deliver the Italian- built “Raffaello” logistics module to the orbiting outpost.

Raffaello is loaded full with about 5 tons of critical space parts, crew supplies and experiments to sustain space station operations once the shuttles are retired at the conclusion of the STS-135 mission, according to Joe Delai, NASA’s Payload Processing Manager for the STS-135 mission.

Close up of top of shuttle Atlantis stack at Launch Pad 39 A
Astronauts will walk through the White Room at left to enter Atlantis crew cabin. Credit: Ken Kremer

NASA technicians at the launch pad have closed the cocoon-like Rotating Service Structure (RSS) back around the orbiter to gain access to the vehicles payload bay. Atlantis’ payload bay doors will be opened Saturday night and the cargo will be installed into the shuttle’s cargo bay on Monday (June 20).

The secondary payload is dubbed the Robotic Refueling Mission (RRM) – a sort of “gas station in space” said Delai, who spoke to me at Pad 39A.

Joe Delai, NASA STS-135 Payload Processing manager, answers media queries at Launch Pad 39A. Credit: Ken Kremer

Pad workers were also busy on Saturday (June 18) with work to begin the collection of high resolution X-ray scans of Atlantis External Tank at certain support ribs on the shuttle facing side, according to Allard Beutel, a NASA KSC shuttle spokesman.

“The technicians will scan the tops and bottoms of 50 support beams, called stringers, to confirm that there are no issues following the tanking test conducted by NASA this week at the launch pad”, Beutel said.

The reinforcing stringers were installed after minute cracks were discovered during the propellant loading of 535,000 gallons of super cold liquid oxygen and hydrogen into the fuel tank during the initial launch attempt of the STS-133 mission in November 2010. “No problems are expected and this work is just being done as a precautionary measure.”

Space Shuttle Atlantis sits atop Launch Complex 39 A at Sunrise at the Kennedy Space Center
The last ever shuttle flight will blast off on July 8. Credit: Ken Kremer

During the tanking test, a potential fuel leak was discovered in a hydrogen fuel valve in Space Shuttle Main Engine No. 3, the right most engine.

“Technicians will spend the next week swapping out the engine valve with a new one and conduct tests to verify the fix solved the problem,” Buetel told me. “NASA expects the work can be completed with no delay to the July 8 launch.”

Space Shuttle Atlantis is set to blastoff on July 8 on NASA’s Final Shuttle Mission; STS-135. Credit: Ken Kremer

The engine leak would have been a show stopper and scrubbed the launch if this had been the real countdown on July 8, said Beutel – to the huge disappointment of the 500,000 to 750,000 folks expected to pack the Florida Space Coast.

The hydrogen valve replacement and X-Ray scans are being completed in parallel out at the pad.

The STS-135 crew of four veteran shuttle astronauts is led by Shuttle Commander Christopher Ferguson. Also aboard are Pilot Doug Hurley and Mission Specialists Sandy Magnus and Rex Walheim.

The crew will fly to into the Kennedy Space Center from Houston aboard their T-38 jets on Monday for several days of pre-launch training.

I will be covering the STS-135 launch for Universe Today on site at the KSC Press site, location of the world famous countdown clock.

Ken Kremer and Space Shuttle Atlantis on top of Launch Pad 39A. Credit: Ken Kremer

Read my prior features about the Final Shuttle mission, STS-135, here:
Last Ever Shuttle Journeys out to the Launch Pad; Photo Gallery
Atlantis Goes Vertical for the Last Time
Atlantis Rolls to Vehicle Assembly Building with Final Space Shuttle Crew for July 8 Blastoff

Posted on by Ken Kremer

Test Roving NASA’s Curiosity on Earth

Mars Rover Curiosity, Front View during mobility testing on June 3, 2011. Credit: NASA/JPL-Caltech

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Just over a year from now, NASA’s Curiosity rover should be driving across fascinating new landscapes on the surface of Mars if all goes well. Curiosity is NASA next Mars rover – the Mars Science Laboratory – and is targeted to launch during a three week window that extends from Nov. 25 to Dec. 18, 2011 from Cape Canaveral Air Force Station, Fla..

At NASA’s Jet Propulsion Laboratory (JPL), Pasadena, Calif., engineering specialists have been putting Curiosity through the final phase of mobility tests to check out the driving capability, robotic arm movements and sample collection maneuvers that the robot will carry out while traversing the landing site after plummeting through the Martian atmosphere in August 2012.

Take a good look at this album of newly released images from JPL showing Curiosity from the front and sides, maneuvering all six wheels, climbing obstacles and flexing the robotic arm and turret for science sample collection activities as it will do while exploring the red planet’s surface.

Mars Rover Curiosity's Arm Held High

Curiosity is following in the footsteps of the legendary Spirit and Opportunity rovers which landed on opposite side of Mars in 2004.

“The rover and descent stage will be delivered to the Payload Hazardous Servicing Facility at the Kennedy Space Center (KSC) later in June,” Guy Webster, public affairs officer at JPL, told me. An Air Force C-17 transport plane has already delivered the heat shield, back shell and cruise stage on May 12, 2011.

“The testing remaining in California is with engineering models and many operational readiness tests,” Webster elaborated. “Lots of testing remains to be done on the flight system at KSC, including checkouts after shipping, a system test, a fit check with the RTG, tests during final stacking.”

Mars Rover Curiosity, Turning in Place during mobility testin. Credit: NASA/JPL-Caltech

The three meter long rover will explore new terrain that will hopefully provide clues as to whether Mars harbored environmental conditions that may have been favorable to the formation of microbial life beyond Earth and preserved evidence of whether left ever existed in the past and continued through dramatic alterations in Mars history.

NASA is evaluating a list of four potential landing sites that will offer the highest science return and the best chance of finding a potentially habitable zone in a previously unexplored site on the red planet.

Mars Rover Curiosity Raising Turret

Mars Rover Curiosity, Left Side View
Mars Rover Curiosity with Wheel on Ramp
Mars Rover Curiosity, Right Side View