NASA launch officials were forced to hit the “destruct” button on an experimental rocket that launched early Friday morning. The launch and subsequent explosion was captured on both amateur and NASA video, and shows the pieces falling back to Earth.
The countdown and initial takeoff Friday morning from a NASA launch facility on Wallops Island, Virginia, went smoothly, said former astronaut Kent Rominger, a vice president in ATK’s (Alliant Tech Systems) launch systems division. “Then (the rocket) appeared to veer south,” he said. To the naked eye the flight didn’t appear to be in trouble, he said, but it was moving off course.
The rocket was a little more than 2 miles high when it was destroyed. A team of officials from NASA and ATK are investigating the incident.
Generations of stars amid a gas cavity. Credit: NASA/JPL-Caltech/Harvard-Smithsonian CfA
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A new image from NASA’s Spitzer Space Telescope reveals generations of stars amid a cavity carved from a colorful cosmic cloud. The striking infrared picture shows a region, called W5, which is similar to N44F, or the “Celestial Geode” that was discussed in a Universe Today article last week. The gas cavity, which looks similar to a geode-like cavity found in some rocks, is carved by the stellar wind and intense ultraviolet radiation from hot stars. W5 is studded with stars of various ages, and provides new evidence that massive stars – through their brute winds and radiation – can trigger the birth of new stars.
The image was unveiled today at the Griffith Observatory in Los Angeles as part of Spitzer’s five-year anniversary celebration. Spitzer launched on August 25, 2003, from Cape Canaveral Air Force Station, Fla. A high-resolution version of the image is available here. It shows a family history full of life and death. But are the deaths of some stars responsible for the birth of new stars?
“Triggered star formation continues to be very hard to prove,” said Xavier Koenig of the Harvard Smithsonian Center for Astrophysics in Cambridge, Mass. “But our preliminary analysis shows that the phenomenon can explain the multiple generations of stars seen in the W5 region.”
The most massive stars in the universe form out of thick clouds of gas and dust. The stars are so massive, ranging from 15 to about 60 times the mass of the Sun, that some of their material slides off in the form of winds. The scorching-hot stars also blaze with intense radiation. Over time, both the wind and radiation blast away surrounding cloud material, carving out expanding cavities.
Astronomers have long suspected that the carving of these cavities causes gas to compress into successive generations of new stars. As the cavities grow, it is believed that more and more stars arise along the cavities’ expanding rims. The result is a radial “family tree” of stars, with the oldest in the middle of the cavity and younger and younger stars farther out.
The astronomer who last week explained the N44F image, Dr. You-Hua Chu from the University of Illinois, said along the walls of the cavity there are dust pillars sticking out and young stars are being formed at the tips of these pillars. Similar features are seen in the new Spitzer image of W5, where younger stars (seen as pink or white in the image) are embedded in the elephant-trunk-like pillars as well, and also beyond the cavity rim. The most massive stars (seen as blue dots) are at the center of two hollow cavities.
With Spitzer’s infrared vision, Koenig and his colleagues peered through the dusty regions of W5 to get a better look at the stars’ various stages of evolution and test the triggered star formation theory. The results from their studies show that stars within the W5 cavities are older than stars at the rims, and even older than stars farther out past the rim. This ladder-like separation of ages provides some of the best evidence yet that massive stars do, in fact, give rise to younger generations.
“Our first look at this region suggests we are looking at one or two generations of stars that were triggered by the massive stars,” said co-author Lori Allen of the Harvard-Smithsonian Center for Astrophysics. “We plan to follow up with even more detailed measurements of the stars’ ages to see if there is a distinct time gap between the stars just inside and outside the rim.” Another version of the image, taken with Spitzer's Infrared Array Camera.
Millions of years from now, the massive stars in W5 will die in tremendous explosions. When they do, they will destroy some of the young nearby stars – the same stars they might have triggered into being.
W5 spans an area of sky equivalent to four full moons and is about 6,500 light-years away in the constellation Cassiopeia. The Spitzer picture was taken over a period of 24 hours. The color red shows heated dust that pervades the region’s cavities. Green highlights the dense clouds, and white knotty areas are where the youngest of stars are forming. The blue dots are older stars in the region, as well as other stars in the background and foreground.
A paper on the findings will appear in the December 1, 2008, issue of the Astrophysical Journal.
[/caption]Greetings, fellow SkyWatchers! Are you ready for a relatively Moon-less weekend? For telescope observers, we’ll travel south and capture the cosmic firefly – the “Bug Nebula”. If you have binoculars, take them out as we journey back 2000 years in time to look at the magnificent M25. For those who like a challenge? Try your luck at being a “Snake” charmer. Even if you just relax in a lawn chair and stare at the stars, you’re in luck because the Northern Iota Aquarid meteor shower is in town for a visit, too! Step out the back door, face south, and let’s journey into the night…
Friday, August 22, 2008 – With the Moon long gone from early evening skies, let’s have a look tonight at NGC 6302, a very curious planetary nebula located around three fingerwidths west of Lambda Scorpii: it is better known as the “Bug” nebula (RA 17 13 44 Dec -37 06 16).
With a rough visual magnitude of 9.5, the Bug belongs to the telescope – but it’s history as a very extreme planetary nebula belongs to us all. At its center is a 10th magnitude star, one of the hottest known. Appearing in the telescope as a small bowtie, or figure 8 shape, huge amounts of dust lie within it – very special dust. Early studies showed it to be composed of hydrocarbons, carbonates and iron. At one time, carbonates were believed associated with liquid water, and NGC 6302 is one of only two regions known to contain carbonates – perhaps in a crystalline form.
Ejected at a high speed in a bi-polar outflow, further research on the dust has shown the presence of calcite and dolomite, making scientists reconsider the kind of places where carbonates might form. The processes that formed the Bug may have begun 10,000 years ago – meaning it may now have stopped losing material. Hanging out about 4000 light-years from our own solar system, we’ll never see NGC 6302 as well as the Hubble Telescope presents its beauty, but that won’t stop you from enjoying one of the most fascinating of planetary nebulae!
Saturday, August 23, 2008 – Do you remember August 10, 1966 when Lunar Orbiter 1 was launched? Well, on this day in history it made headlines as it sent back the very first photo of Earth as seen from space! While the photographic quality is pretty poor by today’s standards, can you imagine the media stir it caused at the time? Never before had humankind witnessed our own planet. Just think of the advances we’ve in just 42 years!
Sunday, August 24, 2008 – Today in 1966 from an Earth-orbiting platform, the Luna 11 mission launched on a three day trip. After successfully achieving orbit, the mission went on to study lunar composition and nearby meteoroid streams. Also on this date in 2006, 424 members of the International Astronomical Union shocked the world as they officially declared Pluto “to no longer be a planet.” Discovered in 1930, Pluto enjoyed its planetary status for 76 years before being retired. While text books will have to be re-written and the amateur science community will continue to recognize it as a solar system body, it is now considered to be a “dwarf planet.” At least temporarily…
So far in our southern expedition we’ve mined for globular gems, had our heads in the clouds and squashed a bug. What’s left? Let’s head over to the dark side as we take a look at the “Snake”…
Snake NebulaBarnard Dark Nebula 72 is located about a fingerwidth north of Theta Ophiuchi (RA 17 23 02 Dec -23 33 48). While sometimes dark nebulae are hard to visualize because they are simply an absence of stars, patient observers will soon learn to “see in the dark.” The trained eye often realizes the presence of unresolved stars as a type of background “noise” that most of us simply take for granted – but not E. E. Barnard. He was sharp enough to realize there were at least 182 areas of the sky where these particular areas of nothingness existed, and he correctly assumed they were nebulae which were obscuring the stars behind them.
Unlike bright emission and reflection nebulae, these dark clouds are interstellar masses of dust and gas which remain unilluminated. We would probably not even know they were there except for the fact they eradicate star fields we know to be present! It is possible one day they may form stars of their own, but until that time we can enjoy these objects as splendid mysteries – and one of the most fascinating of all is the “Snake.” Put in a widefield eyepiece and relax… It will come to you. Barnard 72 is only a few light-years in expanse and a relatively short 650 light-years away. If at first you don’t see it, don’t worry. Like many kinds of objects, spotting dark nebulae takes some practice.
While you’re out, watch for the peak of the Northern Iota Aquarid meteor shower. Even though the official peak isn’t until tomorrow night, with no Moon to interfere and deep sky to enjoy, you might catch a bright streak! Wishing you clear skies and good luck…
This week’s awesome image are: NGC 6302: The Bug Nebula – Credit: Don Goldman, Lunar Orbiter’s first photo – Credit: NASA, M25 – Hillary Mathis, Vanessa Harvey, REU program/NOAO/AURA/NSF and B 72: The Snake Nebula – Credit: Tom McQuillan/Adam Block/NOAO/AURA/NSF. Thank you!!
If glancing at this image takes your attention immediately, it should. Not only is it ethereally beautiful and aesthetically pleasing – but it’s shrouded in bizarre cosmological coincidences. Not only do we see a dazzling array of multi-colored stars, but within this single area of space is a hidden an ancient planetary nebula, a reflection nebula, a dark dust cloud, a Bok globule, a peculiar low-mass protostar, the edges of a massive X-ray bubble and the fringes of a supernova remnant. Hold on to the light of the Cepheus Flare and let’s step inside Wolf’s Cave…
In the northern fringe of Cepheus lay an enigmatic gathering of cosmic dust clouds that first gained the attention of astronomers in 1908 when Max Wolf and August Kopff first noticed its complex structure. Using a 28-inch reflector, Wolf took a 2.5 hour exposure of the dusty area which he described as a “long, dark lacuna” and positively identified the reflection nebula cataloged as Sh2-155. His assistant, Kopff, using the same photographic plate, was the first to note the Bok globule which later became cataloged by E.E. Barnard as B175.
Those were wonderful years for astronomy – years when poetic descriptions were still acceptable to the general consensus and Wolf dubbed the area the “Cave Nebula”. But this isn’t a spelunker’s dream, because the radiation emitted from the nearby bright, young OB star would would obliterate any explorer into this thick knot of interstellar dust. But there was one traveler, who dared – a main sequence star whose course took it through the dust maul at nearly 12 km per second. Running headlong into the obscuring mass at nearly supersonic speeds, the star slammed into Bok globule B175, sending shockwaves rippling through the structure and producing collisional excitation and ultraviolet pumping. The result of this cosmic crash was, of course, noted by Wolf in 1908 on his photographic records, but it was while searching high above the Milky Way’s galactic plane in 1934 that this dusty molecular cloud was was spied by Edwin Hubble and became known as the Cepheus Flare.
Together, reflection nebula Cederblad 201 and Bok globule B175 are referred to as van den Berg 152, and sometimes called Lynds Bright Nebula 524. Yet, it is Cederblad 201 itself that so interests modern science. Why? According to studies done by Goicoechea (et al) with the Spitzer Space Telescope, “We present the detection and characterization of a peculiar low-mass protostar (IRAS 22129+7000) located 0.4 pc from the Cederblad 201. The cold circumstellar envelope surrounding the object has been mapped through its 1.2 mm dust continuum emission with IRAM 30 m/MAMBO. The deeply embedded protostar is clearly detected with Spitzer. Given the large near- and mid-IR excess in its spectral energy distribution, but large submillimeter-to-bolometric luminosity ratio (it) must be a transition Class 0/I source and/or a multiple stellar system. Targeted observations of several molecular lines from CO, 13CO, C18O, HCO+, and DCO+ have been obtained. The presence of a collimated molecular outflow mapped with the CSO telescope in the CO line suggests that the protostar/disk system is still accreting material from its natal envelope. Indeed, optically thick line profiles from high-density tracers such as HCO+ show a redshifted absorption asymmetry reminiscent of inward motions. We construct a preliminary physical model of the circumstellar envelope (including radial density and temperature gradients, velocity field, and turbulence) that reproduces the observed line profiles and estimates the ionization fraction. The presence of both mechanical and (nonionizing) far-ultraviolet (FUV) radiative input makes the region an interesting case to study triggered star formation.”
Star formation? Not surprising deep inside the cave of a molecular cloud, but – if you’ll pardon the pun – the plot thickens. The entire complex is about 1400 light years away from us at the perimeter of yet another massive molecular cloud and at the same time it is situated on the frontier of a massive X-ray bubble located between the constellations of Cepheus and Cassiopeia. And that’s not all. Thanks to hydrogen-alpha imaging, the whisper thin strands of an ancient supernova remnant near Cederblad 201 have also been detected.
Like a radioactive roomba, the interstellar dust is being swept up as the expanding debris field moves toward where the Cepheus Flare lights the entrance to Wolf’s Cave. These shocked molecular gas filaments were discovered in 2001 by John Bally and Bo Reipurth and belong to SNR 110.3+11.3 – a unfathomably huge supernova remnant positioned only 1300 light years way – one of the closest known. Add to that the output of ancient planetary nebula Dengel-Hartl 5 and the celestial stew thickens even more. It is estimated all the elements will combine in about a thousand years and the product could very well ignite an incredible burst of star formation.
But, a thousand years is merely a blink of an eye in the grand scheme of things, isn’t it? According to the 2007 studies done of the Wolf’s Cave region by Edwin Bergin and Mario Tafalla; “Cold dark clouds are nearby members of the densest and coldest phase in the Galactic interstellar medium, and represent the most accessible sites where stars like our Sun are currently being born. Newly discovered IR dark clouds are likely precursors to stellar clusters. At large scales, dark clouds present filamentary mass distributions with motions dominated by supersonic turbulence. At small, subparsec scales, a population of subsonic starless cores provides a unique glimpse of the conditions prior to stellar birth. Recent studies of starless cores reveal a combination of simple physical properties together with a complex chemical structure dominated by the freeze-out of molecules onto cold dust grains. Elucidating this combined structure is both an observational and theoretical challenge whose solution will bring us closer to understanding how molecular gas condenses to form stars.”
Carbonates from the planetary nebula, dust, exciting energy, photoelectric heating, polycyclic aromatic hydrocarbons, molecular gas… Where will it all end? What we do know is massive, bright star clusters are created from the giant molecular clouds. Will the Cepheus Torch one day ignite a brilliant stellar display from the mouth of Wolf’s Cave? I wonder…
The awesome photo for this story was provided by AORAIA member, Kent Wood. We thank you for the use of this splendid image!
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You seem to like a nice series, so here’s a new one Fraser and Pamela have been thinking about. Over the course of the next 4 weeks, they’re going to cover each of the basic forces in the Universe. And this week, they’re going to start with gravity; the force you’re most familiar with. Gravity happens when masses attract one another, and we can calculate its effect with exquisite precision. But you might be surprised to know that scientists have no idea why gravity happens
This ATK rocket exploded shortly after liftoff on Friday. Credit: Jacob Owen | NASA Wallops Flight Facility
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Update: NASA said at a press conference this morning that launch officials were forced to destroy the rocket less than 30 seconds after it’s 5:10 a.m. launch. The rocket had veered off-course, although they couldn’t say how far, and they had to terminate the flight at about 12,000 feet.
A suborbital rocket carrying experiments conducted by NASA exploded early Friday morning 27 seconds after launch on Wallops Island in Virginia. The ATK (Alliant Tech Systems) rocket lifted off with no apparent problems at 5:10 a.m. NASA said no property damage or injuries have occurred, but there were conflicting reports as to whether debris had been sighted on land. NASA said it believes that most of the debris landed in the Atlantic Ocean.
NASA said the debris potentially could be hazardous. People who spot debris are being asked to call Wallops Emergency Operations Center at 757-824-1300.
“NASA is very disappointed in this failure but has directed its focus on protecting public safety and conducting a comprehensive investigation to identify the root cause,” the agency said in a statement. NASA is assembling a multidiscipline team, along with ATK of Salt Lake City, Utah to begin the investigation promptly.
The payload was a 5-in-1 experiment on hypersonic flight, air breathing engines and a rocket recovery system.
Ares V: Heavy lift capability comes with a price (NASA)
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There’s a big problem with Kennedy Space Center playing host to the Constellation Program: The heavy-lift rocket, Ares V, may be too heavy for the infrastructure to cope with. The crawlerway is a 40 year old road designed for the Saturn V (Apollo Program) crawler-transporters and is currently used to carry the Shuttle up to 6.8km (4.2 miles) from assembly building to launch pad. The crawlerway may be unable to withstand the weight of the fully-laden Ares V, transporter and mobile launch pad; a combined weight 33% heavier than anything the Kennedy crawlerway has ever supported. With the Constellation budget getting tighter every day that passes, the possibility of a multi-billion dollar crawlerway upgrade will only create more problems for NASA…
It seems the Good News:Bad News ratio for NASA’s Constellation Project is getting smaller with every news item that is posted. This week, the good news is: NASA may have solved the Ares vibration problem, but the bad news is: NASA has just released images of the failed Orion parachute test, the Constellation spacesuits will need to be produced by a different manufacturer and now we have concerns for the sub-standard infrastructure at Kennedy Space Center. So this week’s ratio so far is 1:3… not good. OK, that wasn’t a very scientific statistical analysis, but it is clear that the Constellation is off to a bumpy start. You could argue that bad news is more likely to make the headlines than good news, but the complications for NASA are becoming problematic and many are concerned that the gap between Shuttle decommissioning and Constellation launch could widen. This issue is now cropping up in the US Presidential race, with both frontrunning candidates (Obama and McCain) making promises for increased space agency funding.
Space Shuttle Discovery inching its way along the Crawlerway to pad 39B (NASA)
So what is wrong with Kennedy’s crawlerway? The combined weight of NASA’s Ares V cargo launch vehicle, its mobile launcher and Constellation crawler-transporter may be too heavy for it to support. After all, the 6.8 km (4.2 mile) crawlerway was built with the Apollo program’s Saturn V in mind, 40 years ago. Fortunately it didn’t require an upgrade when transporting the Shuttle, but the difference in weight from the Shuttle to Ares V is stark. The fully-laden Shuttle (plus crawler and empty external tank) has a mass of 7.7 million kg (16.9 million lb); the fully-laden Ares V could weigh as much as 10.9 million kg (24 million lb). This mass increase could cause significant damage to the crawlerway and, ultimately, damage to Ares V should the existing road be used.
The crawlerway is designed as two 12 metre-wide lanes, separated by 15 metres. It has a surface of the road has 20 cm of river gravel on top of 90 cm of compacted limerock. Under that is two layers of “select fill” 1.1 metres deep.
“Given the projected weight of the Ares V vehicle, mobile launcher and transporter, the total weight is about 33% higher than the crawlerway has ever supported there is a possibility that the crawlerway could fail to support the load, resulting in severe impacts to the Constellation programme.” – Constellation vertical integration element risk assessment.
Unfortunately, in July, NASA administrator Michael Griffin stated that there was no Constellation money left for Kennedy upgrades. So what can be done? For now it looks like Ares V will have to stay inside the assembly building until NASA comes up with a plan (or roll it down the crawlerway and hope for the best! This is probably why I’m not a NASA employee…)
Space Spa on Galactic Suite Hotel. Credit: Galactic Suite
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The space tourism company Galactic Suite already has 38 reservations made by tourists who, the company says, in 2012 will travel on board a magnetically levitated spacecraft to an orbiting luxury hotel, complete with a floating spa, pictured here. The trip, which costs 3 million Euros, will provide four days in orbit 450 kilometers above the earth and includes 18 weeks of training on a Caribbean island for the tourists to prepare for their spaceflight. The Galactic Suite Spaceport is being built on the island and features the first maglev rocket where the spacecraft will accelerate to speeds up to 1,000 km/h (620 mph) in 10 seconds and lift off from a vertical runway.
Galactic Suite Spaceport. Credit: Galactic Suite
After reaching approximately the speed of sound, the spaceship will detach from its maglev carrier and accelerator, and will ascend to orbit using rocket or air-breathing engines. The maglev accelerator will then brake to a stop and return to its starting point for the next launch. The launch track will be about 3 kilometers long.
According to Xavier Claramunt and Marsal Gifra, founders of Galactic Suite, “Maglev launch assist technology will enable space tourists to travel to our space resorts in orbit on a commercial basis. The most expensive part of any space travel to low-Earth orbit is the first few seconds – getting off the ground. This technology is cost competitive with other forms of space transportation, environmentally friendly and inherently safeâ€.
The stay at the hotel will “offer a mixed programme of reflection and exercise to seize the unique physical conditions encountered in space,” said Claramunt.
One of the most innovative experiences that tourists can experience is the bathroom in zero gravity. Galactic Suite has developed the space spa. Inside the spa, tourists can float with 20 liters of water bubbles. According to Galactic Suite materials, “The tourist, already trained to avoid the effects of water in a state of weightlessness, can play with the bubble dividing it into thousands of bubbles in a never-ending game. In addition, the transparent sphere may be shared with other guests.”
Galactic Suite is a private space tourism company, founded in Barcelona in 2006. The company hopes to make space tourism available to the general public and “will combine an intensive program of training astronauts to relax with a programme of activities on a tropical island as a process preparation to space travel.”
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Amateur astronomers have observed the first sunspots to appear on the solar surface for weeks. This period of extreme magnetic calm has made some scientists believe that Solar Cycle 23 might be a quiet affair. This comes in stark contrast to NASA’s 2006 forecast that this cycle would be a “doozy.” Whether or not the slow start of solar activity is indicative of things to come, we’re not sure, but it sure is great to see activity starting to churn on the solar surface once more…
To make the situation even more cloudy, back in March, we had a false alarm. Suddenly, the Sun erupted to life, only three months after the start of Cycle 24 was announced. Sunspots, flares and Coronal Mass Ejections sprung to life around the solar equator. You would have been forgiven for thinking the Sun was going to make good on the NASA 2006 forecast. But it wasn’t to be. Critically, these active sunspots were “left overs” from the previous cycle. Like revellers turning up an hour after the party had finished, these sunspots were overlapping remainders of the previous cycle.
At the root of all these observations is space weather prediction. All our activities in space are in some way influenced by solar activity, so it would be advantageous if we could predict when the next solar storm is coming. We have complex models of the Sun and our observational skills are becoming more and more sophisticated, but we still have a very basic grasp on what makes the Sun “tick.”
So today’s discovery, although a little overdue, will excite solar physicists and astronomers the world over. But will the solar activity continue? Is this just an isolated occurrence? For now, we just do not know. We have to sit back, observe and enjoy what surprises the Sun has in store for us in Cycle 24.
A NASA image of asteroid Eros (left) and Robert Gaskell's shape model of the asteroid (right). Credit: PSI
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Thinking about trekking across Titan or meandering around Mercury? Along with your backpack and towel, you’ll also want to pack one of Robert Gaskell’s maps. Gaskell, a senior scientist at the Planetary Science Institute, is working on creating real hitchhiking guides to the various bodies in our solar system. He’s been equated to the final frontier what Lewis and Clark were to the American West – the guy producing the most accurate and detailed maps available. And thanks to current space missions sending back loads of data, Gaskell is beginning to work on creating precise maps of Mercury, the asteroid Eros, and eight moons of Saturn including Enceladus. Gaskell has created sophisticated software that combines hundreds of spacecraft images of varying resolution to create the maps. He’s been developing the software for nearly 25 years, and if you want to map a planet, moon, or asteroid, he’s the guy to ask.
Gaskell uses a method called stereo-photo-clinometry, or SPC. Just as stereo-phonic means sound from different directions, stereo-photo means light from different directions, and clinometry means that slopes, or inclines, are being measured. So SPC means finding slopes from the way the surface looks under different illuminations, and once we know the slopes we can find the heights.
Four computers in Gaskell’s office grind out mapping data nearly 24/7. But despite his quarter century of mapping work, Gaskell says he’s just getting started. “There are thousands of objects in the solar system, and so far, I’ve barely scratched the surface, if you’ll pardon the expression,” he said.
Gaskell has won an NASA Exceptional Achievement medal for his detailed maps of the asteroid Itokawa. Robert Gaskell. Credit: PSI
His newest project will create highly accurate maps of the entire surface of Mercury based on images sent back by NASA’s MESSENGER spacecraft. MESSENGER flew by Mercury in January and will fly by again in October before going into orbit of Mercury in 2011.
Currently Gaskell is combining images from the January flyby with those taken by Mariner 10, which visited Mercury in 1973, to produce initial maps. But the sun angle for the Mariner 10 photos was the same for three flybys and so far there is only one flyby for MESSENGER.
“It won’t be until we get overlapping data from different sun directions that it will really start making a lot of sense,” Gaskell said. “It does give a reasonable solution now, but I don’t completely trust it.”
Gaskell’s maps not only give scientists useful information about a body’s surface, they also can be used for navigating spacecraft, calibrating spacecraft instruments, and gaining information about the geology, internal structure and past history of an object.
In addition to Mercury, Gaskell is mapping eight of Saturn’s moons, including Enceladus, a frigid world punctuated by icy geysers. In October, NASA may use those maps as navigational tools to plot – and possibly adjust – the Cassini spacecraft’s trajectory as it flies past Enceladus.
Once Gaskell’s computers produce maps covering an entire body, they yield a very accurate image of the object’s shape. The moons of Saturn, for instance, have changed orbits during their history and gravitationally interact with one another. Once their shape became fixed, it recorded the tidal stresses at the time they froze, which gives scientists a way of determining the orbital history of the system.
For Io, Jupiter’s highly volcanic moon, mapping its shape provides planetary geologists with part of the data they need to determine what processes may be going on inside its fluid core, which is being heavily torqued by the giant planet’s intense gravitational field.
Describing himself as an evangelical stereo-photo-clinometrist, he is sharing his work with others and recruiting more researchers into the long-term effort to map the solar system. Some of those are at the Jet Propulsion Laboratory, The University of Arizona, the Johns Hopkins Applied Physics Laboratory, and USGS.
With so many planets, moons and asteroids to explore and map, “It’s like being in a big candy shop,” Gaskell said.
