[/caption] I recently reported on Chinese plans to launch Shenzhou-9, and used a stock image of a Long March-2F rocket blasting off the launch pad. Nafin wanted to know what that diamond pattern trailing behind the rocket was, and ivan3man_at_large posted the answer: they’re called shock diamonds.
Shock diamonds? That term had somehow slipped past me, so I thought I’d dig into it some more.
Shock diamonds (alternatively known as “Mach disks”) occur when gas is exiting a nozzle at supersonic speeds, at a different pressure than the outside atmosphere. At sea level, the exhaust pressure might be lower than the thick atmosphere. And then at very high altitudes, the exhaust pressure might be higher than the thin atmosphere.
So these shock diamonds can appear just as a rocket is taking off, or at high altitude when it shifts into supersonic speed.
A classic example is the space shuttle blasting off, but another famous example is when Chuck Yeager’s X-1 rocket plane reached Mach 1.
Shock diamonds in Chuck Yeager's X-1
Let’s take the example of a rocket blasting off. In this case, the exit pressure of the exhaust is lower than the outside atmosphere, and so you get a situation called “overexpansion”. The gas exits the rocket at a lower pressure, and fans outward from the exhaust nozzle in an “expansion fan”. But the outside atmosphere is higher pressure than the exhaust gas, and so compresses it inward. This difference in pressure forces the gas back together at a specific point – the first shock diamond.
(I’ll spare you all the complex fluid dynamics at this point.)
Then the gas compensates and expands again into a new expansion fan, and then it’s forced back together the same distance further along from the rocket at the next shock diamond, and so on and so on. Eventually atmospheric distortion and friction takes over, equalizing the pressure of the exhaust plume with the ambient atmosphere. Shock diamonds behind the SR-71 Blackbird.
Shock diamonds were originally discovered by Ernst Mach, the famous Austrian scientist who did work on fluid dynamics.
One other interesting side note, shock diamonds aren’t just seen in rocket exhausts. They’ve also been seen blasting out of volcanoes and artillery guns
There are two great articles on Mach diamonds if you really want to understand them more deeply. Check out this article from Aerospace Web and this one from the Allstar Network.
Twin GRAIL Lunar Probes Ebb and Flow Start Lunar Gravity Science. GRAIL probes use precision formation-flying technique to map Lunar Gravity, as depicted in this artist's rendering. Radio signals traveling between the two spacecraft provide scientists with exact measurements which will result in the most accurate gravity map of the moon ever made. Credit: NASA/JPL-Caltech
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NASA’s twin lunar orbiting GRAIL (Gravity Recovery and Interior Laboratory) spacecraft christened Ebb and Flow have kicked off their science collection phase aimed at precisely mapping our Moon’s gravity field, interior composition and evolution, the science team informed Universe Today.
“GRAIL’s science mapping phase officially began Tuesday (March 6) and we are collecting science data,” said Maria Zuber, GRAIL principal investigator of the Massachusetts Institute of Technology in Cambridge, to Universe Today.
“It is impossible to overstate how thrilled and excited we are !”
“The data appear to be of excellent quality,” Zuber told me.
GRAIL’s goal is to provide researchers with a better understanding of how the Moon, Earth and other rocky planets in the solar system formed and evolved over its 4.5 billion years of history.
NASA’s Dawn spacecraft is currently mapping the gravity field of Asteroid Vesta in high resolution from low orbit.
Despite more than 100 missions to the Moon there is still a lot we don’t know about the Moon says Zuber, like why the near side is flooded with magma and smooth and the back side is rough, not smooth and completely different.
South pole of the far side of the moon as seen as seen in this 1st image from the MoonKAM camera aboard GRAIL mission’s Ebb spacecraft. Credit: NASA/JPL-Caltech
The formation-flying spacecraft will make detailed science measurements from lunar orbit with unparalleled precision to within 1 micron – the width of a human red blood cell – by transmitting Ka-band radio signals between each other and Earth to help unlock the mysteries of the Moon’s deep interior.
“We’ve worked on calibrating the alignment of the Ka-band antennae to establish the optimal alignment. We’ve verified the data pipeline and are spending a lot of time working with the raw data to make sure that we understand its intricacies,” Zuber explained.
The washing-machine sized probes have been flying in tandem around the Moon since entering lunar orbit in back to back maneuvers over the New Year’s weekend. Engineers have spent the past two months navigating the spaceship duo into lower, near-polar and near-circular orbits with an average altitude of 34 miles (55 kilometers), that are optimized for science data collection, and simultaneously checking out the spacecraft systems.
GRAIL A and B gravity mappers rocket to the moon atop a Delta II Heavy booster on Sept. 10 from Cape Canaveral, Florida. View to Space Launch Complex 17 gantry from Press Site 1. Credit: Ken Kremer
Ebb and Flow were launched to the Moon on September 10, 2011 aboard a Delta II rocket from Cape Canaveral, Florida and took a circuitous 3.5 month low energy path to the moon to minimize the overall costs. The Apollo astronauts reached the Moon in just 3 days.
I asked Zuber to describe the team’s activities putting the mirror image probes to work peering to the central core of our nearest neighbor in unprecedented detail.
“Last Wednesday (Feb. 29) we achieved the science orbit and on Thursday (March 1) we turned the spacecraft to ‘orbiter point’ configuration to test the instrument and to monitor temperatures and power.”
“When we turned on the instrument we established the satellite-to-satellite radio link immediately. All vital signs were nominal so we left the spacecraft in orbiter point configuration and have been collecting science data since then. At the same time, we’ve continued performing calibrations and monitoring spacecraft and instrument performance, such as temperatures, power, currents, voltages, etc., and all is well,” said Zuber.
Measurements gathered over the next 84 days will be used to create high-resolution maps of the Moon’s near side and far side gravitational fields that are 100 to 1000 times more precise than ever before and that will enable researchers to deduce the internal structure and composition of our nearest neighbor from the outer surface crust down to the deep hidden core.
As one satellite follows the other, in the same orbit, they will perform high precision range-rate measurements to precisely measure the changing distance between each other. As they fly over areas of greater and lesser gravity caused by visible features such as mountains, craters and masses hidden beneath the lunar surface, the distance between the two spacecraft will change slightly.
“GRAIL is great. Everything is in place to get science data now,” said Sami Asmar, a GRAIL co-investigator from NASA’s Jet Propulsion Lab in Pasadena, Calif. “Soon we’ll get a very high resolution and global gravity map of the Moon.”
The data collected will be translated into gravitational field maps of the Moon that will help unravel information about the makeup of the Moon’s core and interior composition.
GRAIL will gather three complete gravity maps over the three month mission which is expected to conclude around May 29. If the probes survive a solar eclipse in June and if NASA funding is available, then they may get a bonus 3 month extended mission.
Ebb and Flow - New Names for the GRAIL Twins in Lunar Orbit
4th Grade Students from Montana (inset) win NASA’s contest to rename the GRAIL A and GRAIL B spacecraft. Artist concept of twin GRAIL spacecraft flying in tandem orbits around the Moon to measure its gravity field Credit: NASA/JPL Montage: Ken Kremer
NASA sponsored a nation-wide student contest for America’s Youth to choose new names for the twin probes originally known as GRAIL A and GRAIL B. 4th graders from the Emily Dickinson Elementary School in Bozeman, Montana submitted the winning entries -Ebb and Flow. The new names won because they astutely describe the probes movements in orbit to collect the science data.
The GRAIL twins are also equipped with a very special camera dubbed MoonKAM (Moon Knowledge Acquired by Middle school students) whose purpose is to inspire kids to study science.
By having their names selected, the 4th graders from Emily Dickinson Elementary have also won the prize to choose the first target on the Moon to photograph with the MoonKAM cameras, which are managed by Dr Sally Ride, America’s first female astronaut.
“MoonKAMs on both Ebb and Flow were turned on Monday, March 5, and all appears well, Zuber said. “The Bozeman 4th graders will have the opportunity to target the first images a week after our science operations begin.”
LROC image of the Apollo 11 landing site, acquired Nov. 5, 2011 (NASA/GSFC/Arizona State University)
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Just over 42 years after Neil and Buzz became the first humans to experience the “stark beauty” of the lunar surface, the Lunar Reconnaissance Orbiter captured the remnants of their visit in the image above, acquired Nov. 5, 2011 from an altitude of only 15 miles (24 km). This is the highest-resolution view yet of the Apollo 11 landing site!
The Lunar Module’s descent stage, a seismic experiment monitor, a laser ranging reflector (LRRR, still used today to measure distances between Earth and the Moon) and its cover, and a camera can be discerned in the overhead image… as well as the darker trails of the astronauts’ bootprints, including Armstrong’s jaunt eastward to the rim of Little West crater.
The crater was the furthest the Apollo astronauts ventured; in fact, if you take the total area Neil and Buzz explored it would easily fit within the infield of a baseball diamond!
Neil Armstrong’s visit to the crater’s edge was an unplanned excursion. He used the vantage point to capture a panoramic image of the historic site:
Panorama of the Apollo 11 site from Little West crater. (NASA)
“Isn’t that something! Magnificent sight out here.” Armstrong had stated before he was joined by Aldrin on the lunar surface. “It has a stark beauty all its own. It’s like much of the high desert of the United States. It’s different, but it’s very pretty out here.”
Previously the LROC captured the Apollo 15 landing site, which included the tracks of the lunar rover — as well as the rover itself! And, just yesterday, the LROC site operated by Arizona State University featured the latest similarly high-resolution view of the Apollo 12 site. This location has the honor of being two landing sites in one: Apollo 12 and the Surveyor 3 spacecraft, which had landed on April 20, 1967 – two and a half years earlier!
The Apollo 12 landing site in Oceanus Procellarum. (NASA/GSFC/Arizona State University)
Even though the US flag planted by Apollo 12 astronauts Pete Conrad and Alan Bean isn’t itself visible, the shadow cast by it is.
Apollo 12 was the only mission to successfully visit the site of a previous spacecraft’s landing, and it also saw the placement of the first Apollo Lunar Surface Experiments Package (ALSEP), which included a seismometer and various instruments to measure the lunar environment.
Read more about this image on the LROC page here, and check out the video tour below of the Apollo 12 site.
Images and video courtesy of NASA/GSFC/Arizona State University
Red Bull Stratos Pilot Felix Baumgartner and his mentor and advisor Joe Kittinger stand proudly aside the capsule developed by Sage Cheshire Aerospace. Credit: Red Bull Stratos.
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Part science experiment, part publicity stunt, part life-long ambition, the Red Bull Stratos mission will feature skydiver Felix Baumgartner attempting to break the speed of sound with his body in a record-setting freefall from the edge of space. The team has been working for over 5 years to build the high-tech capsule that will bring Baumgartner to 36,500 meters (120,000 feet) above Earth, via a stratospheric balloon, and Red Bull Stratos has now released a few images of the capsule. The craft weighs 2,900 pounds fully loaded and it will act as Baumgartner’s life support system during his nearly three-hour ascent. Here’s the outside of the capsule, with Baumgarter standing by, along with the current record holder for such a jump, Joe Kittinger, who jumped from 31,333 meters (102,800 feet) in 1960.
Take a look inside the capsule:
An inside look at the Red Bull Stratos capsule. Credit: Red Bull Stratos.
The pressurized area inside the capsule has of less than 2 meters (6 feet) and contains the flight control panel with 89 different switches and various instrumentation, and a custom-made chair custom to fit Baumgartner and his space suit. It is molded from fiberglass and epoxy, while the door and windows are made of acrylic. The pressure sphere’s interior will be pressurized to 8 pounds per square inch (psi), the equivalent of 16,000 feet above sea level, to reduce the risk of decompression sickness during the ascent without requiring Felix to inflate his pressure suit.
The clear door will give Baumgartner the best view in the stratosphere, but it also puts just half an inch of acrylic between him and the edge of space.
A Chrome-Moly cage and an external foam-insulated shell surrounds the capsule, making it 3.3 meters high (11 feet) and 2.4 meters (8 feet) in diameter at its base.
According to Red Bull Stratos, the capsule will be suspended 45 meters (150 feet) below the balloon, and will protect Baumgartner from stratospheric temperatures reaching minus -55 C (-70 Fahrenheit), providing a pressurized environment during the ascent, with air to breathe so he can avoid decompression sickness. He will inflate his pressure suit only as he prepares to exit the capsule.
Joe Kittinger prepares Felix Baumgartner's checklist to be implemented during his ascent. Credit: Red Bull Stratos.
When Kittinger made his jump, he used a gondola instead of the sealed capsule that Baumgartner will use. Red Bull Stratos says that the additional altitude for this mission means that there are exponentially greater hazards from exposure to freezing temperatures, oxygen deprivation and low air pressure, and the capsule is designed to protect him from that.
The science team collaborated with aerospace engineers to overcome the challenges that the hostile environment of the stratosphere presents to the electronics, radio communications and camera systems vital to the capsule’s operation. They also wanted to build a vessel capable of capturing valuable scientific data as well, to help advance aerospace research. The capsule was designed and hand-constructed at Sage Cheshire Aerospace, Inc. in Lancaster, California.
Once the capsule has completed its ascent and Baumgartner has safely accomplished his mission, a remote triggering system will release the craft from the balloon. Tracked via a GPS system, a recovery parachute will bring the capsule slowly back to Earth, where the data can be extracted and evaluated.
The base of the capsule has a 5 cm (2-inch) thick aluminum honeycomb panel which protects the capsule from sharp objects during landing and provides a mounting for the balloon system control box and batteries. Attached to the base are the landing crush pads, made of a cell-paper honeycomb covered by a fiberglass/epoxy fairing. They are designed to handle as much as 8 Gs on impact. Taking more than 150 drop tests to develop, the crush pads can be used only once and must be replaced after every flight.
The capsule has been thoroughly tested, and the Red Bull Stratos team says they are ready to fly. An exact date for the jump has not been released, but sources say it will likely be in August or September 2012.
Vesta imaged by NASA’s Dawn Asteroid Orbiter. Dawn is currently at work at the Low Altitude Mapping Orbit (LAMO) acquiring new imagery and spectra of much higher resolution compared to these images acquired at higher altitudes and is also filling in gaps of surface data. The image from Dawn’s Framing Camera, at left, was taken on July 24 at a distance of 3,200 miles soon after achieving orbit around Vesta. The mosaic from Dawn’s Visible and infrared spectrometer (VIR), at right, was acquired from High-altitude mapping orbit (HAMO). Credit: NASA/ JPL-Caltech/ UCLA/ ASI/ INAF/ IAPS. Collage: Ken Kremer
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NASA’s Dawn mission is getting a whopping boost in science observing time at the closest orbit around Asteroid Vesta as the probe passes the midway point of its 1 year long survey of the colossal space rock. And the team informs Universe Today that the data so far have surpassed all expectations and they are very excited !
Dawn’s bonus study time amounts to an additional 40 days circling Vesta at the highest resolution altitude for scientific measurements. That translates to a more than 50 percent increase beyond the originally planned length of 70 days at what is dubbed the Low Altitude Mapping Orbit, or LAMO.
“We are truly thrilled to be able to spend more time observing Vesta from low altitude,” Dr. Marc Rayman told Universe Today in an exclusive interview. Rayman is Dawn’s Engineer at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.
“It is very exciting indeed to obtain such a close-up look at a world that even a year ago was still just a fuzzy blob.”
The big extension for a once-in-a-lifetime shot at up close science was all enabled owing to the hard work of the international science team in diligently handling any anomalies along the pathway through interplanetary space and since Dawn achieved orbit in July 2011, as well as to the innovative engineering of the spacecraft’s design and its revolutionary ion propulsion system.
“This is a reflection of how well all of our work at Vesta has gone from the beginning of the approach phase in May 2011,” Rayman told me.
Simulated view of Vesta from Dawn in LAMO, low altitude mapping orbit - March, 6 2012
Credit: Gregory J. Whiffen, JPL
Dawn’s initially projected 10 week long science campaign at LAMO began on Dec. 12, 2011 at an average distance of 210 kilometers (130 miles) from the protoplanet and was expected to conclude on Feb. 20, 2012 under the original timeline. Thereafter it would start spiraling back out to the High Altitude Mapping Orbit, known as HAMO, approximately 680 kilometers above the surface.
“With the additional 40 days it means we are now scheduled to leave LAMO on April 4. That’s when we begin ion thrusting for the transfer to HAMO2,” Rayman stated.
And the observations to date at LAMO have already vastly surpassed all hopes – using all three of the onboard science instruments provided by the US, Germany and Italy.
“Dawn’s productivity certainly is exceeding what we had expected,” exclaimed Rayman.
“We have acquired more than 7500 LAMO pictures from the Framing Camera and more than 1 million LAMO VIR (Visible and Infrared) spectra which afford scientists a much more detailed view of Vesta than had been planned with the survey orbit and the high altitude mapping orbit (HAMO). It would have been really neat just to have acquired even only a few of these close-up observations, but we have a great bounty!”
“Roughly around half of Vesta’s surface has been imaged at LAMO.”
Dawn mosaic of Visible and Infrared spectrometer (VIR) data of Vesta
This mosaic shows the location of the data acquired by VIR (visible and infrared spectrometer) during the HAMO (high-altitude mapping orbit) phase of the Dawn mission from August to October 2011. Dawn is now making the same observations at the now extended LAMO (low-altitude mapping orbit) phase of the Dawn mission from December 2011 to April 2012. VIR can image Vesta in a number of different wavelengths of light, ranging from the visible to the infrared part of the electromagnetic spectrum. This mosaic shows the images taken at a wavelength of 550 nanometers, which is in the visible part of the electromagnetic spectrum. During HAMO VIR obtained more than 4.6 million spectra of Vesta. It is clear from this image that the VIR observations are widely distributed across Vesta, which results in a global view of the spectral properties of Vesta’s surface. This image shows Vesta’s southern hemisphere (lower part of the image) and equatorial regions (upper part of the image). NASA’s Dawn spacecraft obtained these VIR images with its visible and infrared spectrometer in September and October 2011. The distance to the surface of Vesta is around 700 kilometers (435 miles) and the average image resolution is 170 meters per pixel. Credit: NASA/ JPL-Caltech/ UCLA/ ASI/ INAF/ IAPS
The bonus time at LAMO will now be effectively used to help fill in the gaps in surface coverage utilizing all 3 science instruments. Therefore perhaps an additional 20% to 25% extra territory will be imaged at the highest possible resolution. Some of this will surely amount to enlarged new coverage and some will be overlapping with prior terrain, which also has enormous research benefits.
“There is real value even in seeing the same part of the surface multiple times, because the illumination may be different. In addition, it helps for building up stereo,” said Rayman.
Researchers will deduce further critical facts about Vesta’s topography, composition, interior, gravity and geologic features with the supplemental measurements.
Successive formation of impact craters on Vesta
This Dawn FC (framing camera) image shows two overlapping impact craters and was taken on Dec. 18,2011 during the LAMO (low-altitude mapping orbit) phase of the mission. The large crater is roughly 20 kilometers (12 miles) in diameter and the smaller crater is roughly 6 kilometers (4 miles) in diameter. The rims of the craters are both reasonably fresh but the larger crater must be older because the smaller crater cuts across the larger crater’s rim. As the smaller crater formed it destroyed a part of the rim of the pre-existing, larger crater. The larger crater’s interior is more densely cratered than the smaller crater, which also suggests that is it older. In the bottom of the image there is some material slumping from rim of the larger crater towards its center. This image with its framing camera on Dec. 18, 2011. This image was taken through the camera’s clear filter. The distance to the surface of Vesta is 260 kilometers (162 miles) and the image has a resolution of about 22 meters (82 feet) per pixel. Credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA
The foremost science goals at LAMO are collection of gamma ray and neutron measurements with the GRaND instrument – which focuses on determining the elemental abundances of Vesta – and collection of information about the structure of the gravitational field. Since GRaND can only operate effectively at low orbit, the extended duration at LAMO takes on further significance.
“Our focus is on acquiring the highest priority science. The pointing of the spacecraft is determined by our primary scientific objectives of collecting GRaND and gravity measurements.”
As Dawn continues orbiting every 4.3 hours around Vesta during LAMO, GRaND is recording measurements of the subatomic particles that emanate from the surface as a result of the continuous bombardment of cosmic rays and reveals the signatures of the elements down to a depth of about 1 meter.
“You can think of GRaND as taking a picture of Vesta but in extremely faint light. That is, the nuclear emissions it detects are extremely weak. So our long time in LAMO is devoted to making a very, very long exposure, albeit in gamma rays and neutrons and not in visible light,” explained Rayman.
Now with the prolonged mission at LAMO the team can gather even more data, amounting to thousands and thousands more pictures, hundreds of thousands of more VIR spectra and ultra long exposures by GRaND.
“HAMO investigations have already produced global coverage of Vesta’s gravity field,” said Sami Asmar, a Dawn co-investigator from JPL. Extended investigations at LAMO will likewise vastly improve the results from the gravity experiment.
Dawn Spacecraft Current Location and Trajectory - March, 6 2012. Credit: Gregory J. Whiffen, JPL
“We always carried 40 days of “margin,” said Rayman, “but no one who was knowledgeable about the myriad challenges of exploring this uncharted world expected we would be able to accomplish all the complicated activities before LAMO without needing to consume some of that margin. So although we recognized that we might get to spend some additional time in LAMO, we certainly did not anticipate it would be so much.”
“As it turned out, although we did have surprises the operations team managed to recover from all of them without using any of those 40 days.”
“This is a wonderful bonus for science,” Rayman concluded.
“We remain on schedule to depart Vesta in July 2012, as planned for the past several years.”
Dawn’s next target is Ceres, the largest asteroid in the main Asteroid Belt between Mars and Jupiter
Artist rendition of NASA’s Mars InSight (Interior exploration using Seismic Investigations, Geodesy and Heat Transport) Lander. InSight is based on the proven Phoenix Mars spacecraft and lander design with state-of-the-art avionics from the Mars Reconnaissance Orbiter (MRO) and Gravity Recovery and Interior Laboratory (GRAIL) missions. Credit: JPL/NASA
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A Phoenix-like lander that would mine the deepest hole yet into Mars– to a depth of 5 meters – and unveil the nature of the mysterious deep interior and central core of the Red Planet is under consideration by NASA for a 2016 launch and sports a nifty new name – InSight.
The stationary “InSight” lander would be an international science mission and a near duplicate of NASA’s proven Phoenix spacecraft, Bruce Banerdt told Universe Today. Banerdt is the Principal Investigator of the proposed InSight mission.
“InSight is essentially built from scratch, but nearly build-to-print from the Phoenix design,” Banerdt, of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena , Calif, told me. The team can keep costs down by re-using the blueprints pioneered by Phoenix instead of creating an entirely new spacecraft.
“The robotic arm is similar (but not identical) to the Phoenix arm.”
Mars Interior
Insight’s goal is to investigate and deduce the nature of the interior of the Red Planet. Credit: JPL/NASA
However, the landing site and science goals for InSight are quite different from Phoenix.
InSight will have an entirely new suite of three science instruments, including two from Europe, designed to peer to the center of Mars and detect the fingerprints of the processes by which the terrestrial planets formed. It will determine if there is any seismic activity, the amount of heat flow from the interior, the size of Mars core and whether the core is liquid or solid.
NASA’s twin GRAIL lunar gravity probes are set to begin their own investigation into the interior and core of Earth’s Moon in early March 2012, and several science team members are common to GRAIL and InSight.
“The seismometer (SEIS, stands for Seismic Experiment for Interior Structure) is from France (built by CNES and IPGP) and the heat flow probe (HP3, stands for Heat flow and Physical Properties Probe) is from Germany (built by DLR),” Banerdt explained.
Phoenix successfully landed in the frigid northern polar regions of Mars in 2008 in search of potential habitats for life and quickly discovered water ice and salty soils that could be favorable for the genesis and support of extraterrestrial life.
3 Footpads of Phoenix Mars Lander atop Martian Ice
Phoenix thrusters blasted away Martian soil and exposed water ice. Proposed Mars InSight mission will build a new Phoenix-like lander from scratch to peer deep into the Red Planet and investigate the nature and size of the mysterious Martian core. Credit: Kenneth Kremer, Marco Di Lorenzo, Phoenix Mission, NASA/JPL/UA/Max Planck Institute
InSight will intentionally land in a far warmer and sunnier location nearer the moderate climate of the equator to enable a projected lifetime of 2 years (or 1 Mars year) vs. the 5 months survival of Phoenix extremely harsh arctic touchdown zone.
“Our planned landing site is in Elysium Planitia,” Banerdt told me. “It was chosen for optimizing engineering safety margins for landing and power.”
The more equatorial landing site affords far more sun for the life giving solar arrays to power the instruments and electronics.
“We have global objectives and can do our science anywhere on the planet.”
Elysium Planitia is not too far from the landing sites of the Spirit and Curiosity rovers. The Elysium Mons volcano is also in the general area, but it’s a long way from precise site selection.
InSight is a geophysical lander targeted to delve deep beneath the surface into the Martian interior, check its “vital signs”; like “pulse” though seismology, “temperature”, though a heat flow probe, and “reflexes”, through precision tracking.
The purpose is to answer one of science’s most fundamental questions: How were the planets created?
InSight will accomplish much of its science investigations through experiments sitting directly in contact with the Martian surface. The robotic arm will pluck two of the instruments from the lander deck and place them onto Mars.
“The arm will pick the SEIS seismometer and HP3 heat flow probe off the deck and place each on the ground next to the lander. The arm doesn’t have a drill, but the heat flow probe itself will burrow down as deep as 5 meters,” Banerdt elaborated.
The third experiment named RISE (Rotation and Interior Structure Experiment) is to be provided by JPL and will use the spacecraft communication system to provide precise measurements of Mars planetary rotation and elucidate clues to its interior structure and composition.
Right now on Mars, NASA’s Opportunity rover is conducting a Doppler radio tracking experiment similar to what is planned for RISE, but InSight will have a big advantage according to Banerdt.
“The RISE experiment will be very similar to what we are doing right now on Opportunity, but will be able to do much better, said Banerdt. “The differences are that we will get more tracking every week (Opportunity is power-limited during the winter months; that’s why she is currently stationary!) and will make measurements for an entire Mars year – we will likely only get a handful of months from Opportunity.”
Insight will also be equipped with 2 cameras and make some weather measurements.
“We have a camera on the arm and one fixed to the deck, both primarily to support placing the instruments on the surface, although they will be able to scan the landscape around the spacecraft. Both are Black & White,” Banerdt told me.
“We will measure pressure, temperature and wind, mostly to support noise analysis on the seismic data, but will also supply information on the weather.”
Mars has the same basic internal structure as the Earth and other terrestrial (rocky) planets. It is large enough to have pressures equivalent to those throughout the Earth's upper mantle, and it has a core with a similar fraction of its mass. In contrast, the pressure even near the center of the Moon barely reach that just below the Earth's crust and it has a tiny, almost negligible core. The size of Mars indicates that it must have undergone many of the same separation and crystallization processes that formed the Earth's crust and core during early planetary formation. Credit: JPL/NASA
InSight is one of three missions vying to be selected for flight in NASA’s Discovery Program, a series of low cost NASA missions to understand the solar system by exploring planets, moons, and small bodies such as comets and asteroids. All three mission teams are required to submit concept study reports to NASA on March 19.
Banerdt’s team is working hard to finalize the concept study report.
“It describes the mission design as we have refined it over the past 9 months since the NASA Step-1 selection.”
So there is no guarantee that InSight will fly. Because of severe budget cuts to NASA’s Planetary Science Division, NASA had to cancel its scheduled participation in two other Mars missions dubbed ExoMars and jointed planned with ESA, the European Space Agency, for launch in 2016 and 2018.
Dropping out of warp speed could have deadly results. (Image: Paramount Pictures/CBS Studios)
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Planning a little space travel to see some friends on Kepler 22b? Thinking of trying out your newly-installed FTL3000 Alcubierre Warp Drive to get you there in no time? Better not make it a surprise visit — your arrival may end up disintegrating anyone there when you show up.
“Warp” technology and faster-than-light (FTL) space travel has been a staple of science fiction for decades. The distances in space are just so vast and planetary systems — even within a single galaxy — are spaced so far apart, such a concept is needed to make casual human exploration feasible (and fit within the comforts of people’s imagination as well… nobody wants to think about Kirk and Spock bravely going to some alien planet while everyone they’ve ever known dies of old age!)
While many factors involving FTL travel are purely theoretical — and may remain in the realm of imagination for a very long time, if not ever — there are some concepts that play well with currently-accepted physics.
Warp field according to the Alcubierre drive. (AllenMcC.)
The Alcubierre warp drive is one of those concepts.
Proposed by Mexican theoretical physicist Miguel Alcubierre in 1994, the drive would propel a ship at superluminal speeds by creating a bubble of negative energy around it, expanding space (and time) behind the ship while compressing space in front of it. In much the same way that a surfer rides a wave, the bubble of space containing the ship and its passengers would be pushed at velocities not limited to the speed of light toward a destination.
Of course, when the ship reaches its destination it has to stop. And that’s when all hell breaks loose.
Researchers from the University of Sydney have done some advanced crunching of numbers regarding the effects of FTL space travel via Alcubierre drive, taking into consideration the many types of cosmic particles that would be encountered along the way. Space is not just an empty void between point A and point B… rather, it’s full of particles that have mass (as well as some that do not.) What the research team — led by Brendan McMonigal, Geraint Lewis, and Philip O’Byrne — has found is that these particles can get “swept up” into the warp bubble and focused into regions before and behind the ship, as well as within the warp bubble itself.
When the Alcubierre-driven ship decelerates from superluminal speed, the particles its bubble has gathered are released in energetic outbursts. In the case of forward-facing particles the outburst can be very energetic — enough to destroy anyone at the destination directly in front of the ship.
“Any people at the destination,” the team’s paper concludes, “would be gamma ray and high energy particle blasted into oblivion due to the extreme blueshifts for [forward] region particles.”
In other words, don’t expect much of a welcome party.
Another thing the team found is that the amount of energy released is dependent on the length of the superluminal journey, but there is potentially no limit on its intensity.
“Interestingly, the energy burst released upon arriving at the destination does not have an upper limit,” McMonigal told Universe Today in an email. “You can just keep on traveling for longer and longer distances to increase the energy that will be released as much as you like, one of the odd effects of General Relativity. Unfortunately, even for very short journeys the energy released is so large that you would completely obliterate anything in front of you.”
So how to avoid disintegrating your port of call? It may be as simple as just aiming your vessel a bit off to the side… or, it may not. The research only focused on the planar space in front of and behind the warp bubble; deadly postwarp particle beams could end up blown in all directions!
Luckily for Vulcans, Tatooinians and any acquaintances on Kepler 22b, the Alcubierre warp drive is still very much theoretical. While the mechanics work with Einstein’s General Theory of Relativity, the creation of negative energy densities is an as-of-yet unknown technology — and may be impossible.
Which could be a very good thing for us, should someone out there be planning a surprise visit our way!
Read more about Alcubierre warp drives here, and you can download the full University of Sydney team’s research paper here.
Thanks to Brendan McMonigal and Geraint Lewis for the extra information!
NASA's Mars rover Curiosity carries a Lincoln Penny on the calibration target to be used by a camera at the end of the robotic arm. The calibration target for the Mars Hand Lens Imager (MAHLI) camera is attached to a shoulder joint of the arm. Inset shows the location of the calibration target. Credit: NASA/JPL-Caltech
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NASA’s huge Curiosity Mars Science Lab (MSL) rover is carrying a vintage Lincoln penny along for the long interplanetary journey to Mars – and it’s not to open the first Martian savings account.
Scientists will use the century old Lincoln penny – minted back in 1909 – as a modern age calibration target for one of Curiosity’s five powerful science cameras attached to the end of the hefty, 7 foot (2.1 meter) long robotic arm.
The car sized rover is on course to touchdown at the foothills of a towering and layered mountain inside Gale Crater in just 161 days on Aug. 6, 2012.
So far Curiosity has traveled 244 million kilometers since blasting off on Nov. 26, 2011 from Florida and has another 322 million kilometers to go to the Red Planet.
The copper penny is bundled to a shoulder joint on the rovers arm along with the other elements of the calibration target, including color chips, a metric standardized bar graphic, and a stair-step pattern for depth calibration.
The whole target is about the size of a smart phone and looks a lot like an eye vision chart in an ophthalmologist’s office. And it serves a similar purpose, which will be to check the performance of Curiosity eyes – specifically the Mars Hand Lens Imager (MAHLI) camera located at the terminus of the robotic arm.
Curiosity’s Calibration Target
Two instruments at the end of the robotic arm on NASA's Mars rover Curiosity will use calibration targets attached to a shoulder joint of the arm. Credit: NASA/JPL-Caltech
MAHLI will conduct close-up inspections of Martian rocks and soil. It can show tiny details, finer than a human hair.
The term “hand lens” in MAHLI’s name refers to the standard practice by field geologists’ of carrying a hand lens during expeditions for close up, magnified inspection of rocks they find along the way. So it’s also critical to pack various means of calibration so that researchers can interpret their results and put them into proper perspective.
MAHLI can also focus on targets over a wide range of distances near and far, from about a finger’s-width away out to the Red Planets horizon, which in this case means the mountains and rim of the breathtaking Gale Crater landing site.
“When a geologist takes pictures of rock outcrops she is studying, she wants an object of known scale in the photographs,” said MAHLI Principal Investigator Ken Edgett, of Malin Space Science Systems, San Diego, which supplied the camera to NASA.
Curiosity Mars Science Laboratory Rover - inside the Cleanroom at KSC
Curiosity with robotic arm extended. Calibration target is located at a shoulder joint on the arm. Photo taken just before encapsulation for 8 month long interplanetary Martian Journey and touchdown inside Gale Crater. Credit: Ken Kremer
The target features a collection of marked black bars in a wide range of labeled sizes to correlate calibration images to each image taken by Curiosity.
“If it is a whole cliff face, she’ll ask a person to stand in the shot. If it is a view from a meter or so away, she might use a rock hammer. If it is a close-up, as the MAHLI can take, she might pull something small out of her pocket. Like a penny.”
Edgett donated the special Lincoln penny with funds from his own pocket. The 1909 “VDB” cent stems from the very first year that Lincoln pennies were minted and also marks the centennial of President Abraham Lincoln’s birth. The VDB initials of the coin’s designer – Victor David Brenner — are on the reverse side. In mint condition the 1909 Lincoln VDB copper penny has a value of about $20.
The Lincoln penny in this photograph is part of a camera calibration target attached to NASA's Mars rover Curiosity. Credit: NASA/JPL-Caltech
“The penny is on the MAHLI calibration target as a tip of the hat to geologists’ informal practice of placing a coin or other object of known scale in their photographs. A more formal practice is to use an object with scale marked in millimeters, centimeters or meters,” Edgett said. “Of course, this penny can’t be moved around and placed in MAHLI images; it stays affixed to the rover.”
“Everyone in the United States can recognize the penny and immediately know how big it is, and can compare that with the rover hardware and Mars materials in the same image,” Edgett said.
“The public can watch for changes in the penny over the long term on Mars. Will it change color? Will it corrode? Will it get pitted by windblown sand?”
MAHLI’s calibration target also features a display of six patches of pigmented silicone to assist in interpreting color and brightness in the images. Five of them are leftovers from Spirit and Opportunity. The sixth has a fluorescent pigment that glows red when exposed to ultraviolet light, allows checking of an ultraviolet light source on MAHLI. The fluorescent material was donated to the MAHLI team by Spectra Systems, Inc., Providence, R.I.
Three-dimensional calibration of the MSL images will be done using the penny and a stair-stepped area at the bottom of the target.
“The importance of calibration is to allow data acquired on Mars to be compared reliably to data acquired on Earth,” said Mars Science Laboratory Project Scientist John Grotzinger, of the California Institute of Technology, Pasadena.
Curiosity is a 1 ton (900 kg) behemoth. She measures 3 meters (10 ft) in length and is nearly twice the size and five times as heavy as Spirit and Opportunity, NASA’s prior set of twin Martian robots. The science payload is 15 times heavier than the twin robots.
Curiosity is packed to the gills with 10 state of the art science instruments that are seeking the signs of life in the form of organic molecules – the carbon based building blocks of life as we know it.
NASA could only afford to build one rover this time.
Curiosity MSL location on 27 Feb 2012. Credit: NASA
Curiosity will be NASA’s last Mars rover since the 4th generation ExoMars rover due to liftoff in 2018 was just cancelled by the Obama Administration as part of a deep slash to NASA’s Planetary Science budget.
Feb. 24, 2012 launch of Atlas V with MUOS-1. Credit: Jen Scheer (@flyingjenny)
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On the afternoon of February 24, 2012, at 5:15 p.m. EST local time, a United Launch Alliance Atlas V rocket lifted off from the pad at Cape Canaveral Air Force Base carrying in its payload the US Navy’s next-generation narrowband communications satellite MUOS-1. After two scrubbed launches the previous week due to weather, the third time was definitely a charm for ULA, and the launch went nominally (that’s science talk for “awesome”.)
But what made that day, that time the right time to launch? Do they just like ending a work week with a rocket launch? (Not that I could blame them!) And what about the weather… why go through the trouble to prepare for a launch at all if the weather doesn’t look promising? Where’s the logic in that?
As it turns out, when it comes to launches, it really is rocket science.
There are a lot of factors involved with launches. Obviously all the incredible engineering it takes to even plan and build a launch vehicle, and of course its payload — whatever it happens to be launching in the first place. But it sure doesn’t end there.
Launch managers need to take into consideration the needs of the mission, where the payload has to ultimately end up in orbit… or possibly even beyond. Timing is critical when you’re aiming at moving targets — in this case the targets being specific points in space (literally.) Then there’s the type of rocket being used, and where it is launching from. Only then can weather come into the equation, and usually only at the last minute to determine if the countdown will proceed before the launch window closes.
How big that launch window may be — from a few hours to a few minutes — depends on many things.
Kennedy Space Center’s Anna Helney recently assembled an article “Aiming for an Open Window” that explains how this process works:
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The most significant deciding factors in when to launch are where the spacecraft is headed, and what its solar needs are. Earth-observing spacecraft, for example, may be sent into low-Earth orbit. Some payloads must arrive at a specific point at a precise time, perhaps to rendezvous with another object or join a constellation of satellites already in place. Missions to the moon or a planet involve aiming for a moving object a long distance away.
For example, NASA’s Mars Science Laboratory spacecraft began its eight-month journey to the Red Planet on Nov. 26, 2011 with a launch aboard a United Launch Alliance (ULA) Atlas V rocket from Cape Canaveral Air Force Station in Florida. After the initial push from the powerful Atlas V booster, the Centaur upper stage then sent the spacecraft away from Earth on a specific track to place the laboratory, with its car-sized Curiosity rover, inside Mars’ Gale Crater on Aug. 6, 2012. Due to the location of Mars relative to Earth, the prime planetary launch opportunity for the Red Planet occurs only once every 26 months.
Additionally, spacecraft often have solar requirements: they may need sunlight to perform the science necessary to meet the mission’s objectives, or they may need to avoid the sun’s light in order to look deeper into the dark, distant reaches of space.
A Delta II arcs across the sky carrying NASA's Suomi NPP spacecraft. Image credit: NASA/Bill Ingalls
Such precision was needed for NASA’s Suomi National Polar-orbiting Partnership (NPP) spacecraft, which launched Oct. 28, 2011 aboard a ULA Delta II rocket from Vandenberg Air Force Base in California. The Earth-observing satellite circles at an altitude of 512 miles, sweeping from pole to pole 14 times each day as the planet turns on its axis. A very limited launch window was required so that the spacecraft would cross the ascending node at exactly 1:30 p.m. local time and scan Earth’s surface twice each day, always at the same local time.
All of these variables influence a flight’s trajectory and launch time. A low-Earth mission with specific timing needs must lift off at the right time to slip into the same orbit as its target; a planetary mission typically has to launch when the trajectory will take it away from Earth and out on the correct course.
According to [Eric Haddox, the lead flight design engineer in NASA’s Launch Services Program], aiming for a specific target — another planet, a rendezvous point, or even a specific location in Earth orbit where the solar conditions will be just right — is a bit like skeet shooting.
“You’ve got this object that’s going to go flying out into the air and you’ve got to shoot it,” said Haddox. “You have to be able to judge how far away your target is and how fast it’s moving, and make sure you reach the same point at the same time.”
But Haddox also emphasized that Earth is rotating on its axis while it orbits the sun, making the launch pad a moving platform. With so many moving players, launch windows and trajectories must be carefully choreographed.
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It’s a fascinating and complex set of issues that mission managers need to get just right in order to ensure the success of a launch — and thus the success of a mission, whether it be putting a communication satellite into orbit or a rover onto Mars… or somewhere much, much farther than that.
Here’s a gorgeous view from the International Space Station, taken by the Expedition 30 crew on Feb. 4, 2012 as the station passed into orbital dawn. The greens and reds of the aurora borealis shimmer above Earth’s limb beyond the Station’s solar panels as city lights shine beneath a layer of clouds.
As the ISS travels around the planet at 17,500 mph (28,163 km/h) it moves in and out of daylight, in effect experiencing dawn 16 times every day.
From that vantage point, 240 miles (386 km) above the Earth, the lights of the aurora — both northern and southern — appear below, rather than above.
See this and more images from the Space Station’s nightly flights here.
Also, here’s a time-lapse video made from photos taken by the Expedition 30 crew a few days earlier. Enjoy!
(Video courtesy of the Image Science & Analysis Laboratory, NASA Johnson Space Center.)
