This week’s Carnival of Space is hosted by Ian O’Neill over at Discovery News/Space, (and formerly of Universe Today!) who has given the Carnival the “Red Carpet” treatment.
And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, let Fraser know if you can be a host, and he’ll schedule you into the calendar.
Finally, if you run a space-related blog, please post a link to the Carnival of Space. Help us get the word out.
Details from the Ascraeus channel (red), meandering across the surface of Mars. The insets in the black boxes show close-ups of some of the structures that lava can form: (left) branched channels, (middle) a snaking channel and (right) rootless vents; the rootless vents are also marked by yellow spots on the main image. Credit: Jacob Bleacher
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Images of Mars taken from orbit show a massive system of riverbeds and canyons etched by water. Or maybe not. A new study of one channel shows that it was formed by lava flow and not water, and the results make “a strong case that fluid lava can produce channels that look very much like water-generated features,” said Jim Zimbelman from the Smithsonian Institution in Washington, one of the researchers. “So, we should not jump to a water-related conclusion when we see such channels on other planets.”
Whether channels on Mars were formed by water or by lava has been debated for years and the outcome is thought to influence the likelihood of finding life there. Images from various Mars orbiters reveal details resembling the erosion of soil by water: terracing of channel walls, formation of small islands in a channel, hanging channels that dead-end and braided channels that branch off and then reconnect to the main branch. “These are thought to be clear evidence of fluvial [water-based] erosion on Mars,” said Jacob Bleacher from Goddard Spaceflight Center, who presented the results at the Lunar and Planetary Science Conference last week.
Lava flow usually creates big, open channels, such as the ones commonly seen in Hawaii. But detailed looks at both channels on Mars and in Hawaii shed a whole new light on the formation of channels and other features on Mars.
The research team carried out a careful study of a single channel on the southwest flank of Mars’ Ascraeus Mons volcano, one of the three clustered volcanoes collectively called the Tharsis Montes. To piece together images covering more than 270 kilometers (~168 miles) of this channel, the team relied on high-resolution pictures from three cameras—the Thermal Emission Imaging System (THEMIS), the Context Imager (CTX) and the High/Super Resolution Stereo Color (HRSC) imager—as well as earlier data from the Mars Orbiter Laser Altimeter (MOLA). These data gave a much more detailed view of the surface than previously available.
Because the fluid that formed this and other Ascraeus Mons channels is long-gone, its identity has been hard to deduce, but the visual clues at the source of the channel seem to point to water. These clues include small islands, secondary channels that branch off and rejoin the main one and eroded bars on the insides of the curves of the channels. The Tharsis region of Mars, including the three volcanoes of Tharsis Montes (Arsia, Pavonis and Ascraeus Mons), as well as Olympic Mons in the upper left corner. Credit: NASA/Jet Propulsion Lab
But at the channel’s other end, an area not clearly seen before, the team found a ridge that appears to have lava flows coming out of it. In some areas, “the channel is actually roofed over, as if it were a lava tube, and lined up along this, we see several rootless vents,” or openings where lava is forced out of the tube and creates small structures, he explains. These types of features don’t form in water-carved channels, he notes. Bleacher argues that having one end of the channel formed by water and the other end by lava is an “exotic” combination. More likely, he thinks, the entire channel was formed by lava.
To find out what kinds of features lava can produce, Bleacher, Zimbelman and W. Brent Garry examined the 51-kilometer (~32 mile) lava flow from the 1859 eruption of Mauna Loa on the Big Island of Hawaii. Their main focus was an island nearly a kilometer long in the middle of the channel; Bleacher says this is much larger than islands typically identified within lava flows. To survey the island, the team used differential GPS, which provides location information to within about 3 to 5 centimeters (1.1 to 1.9 inches), rather than the roughly 3 to 5 meters (9.8 to 16.4 feet) that a car’s GPS can offer.
“We found terraced walls on the insides of these channels, channels that go out and just disappear, channels that cut back into the main one, and vertical walls 9 meters (~29 feet) high,” Bleacher says. “So, right here, in something that we know was formed only by flowing lava, we found most of the features that were considered to be diagnostic of water-carved channels on Mars.”
Further evidence that such features could be created by lava flows came from the examination of a detailed image of channels from the Mare Imbrium, a dark patch on the moon that is actually a large crater filled with ancient lava rock. In this image, too, the researchers found channels with terraced walls and branching secondary channels.
The conclusion that lava probably made the channel on Mars “not only has implications for the geological evolution of the Ascraeus Mons but also the whole Tharsis Bulge [volcanic region],” says Andy de Wet, a co-author at Franklin & Marshall College, Lancaster, Penn. “It may also have some implications for the supposed widespread involvement of water in the geological evolution of Mars.”
President Obama will travel to Florida to unveil an “ambitious plan for NASA that sets the agency on a reinvigorated path of space exploration,” according to a press release from the White House. The President will host a conference on April 15, inviting space officials and leaders to discuss the new budget and plan for NASA and the future of U.S. leadership in human space flight. The location was not yet disclosed, but it likely will be at Kennedy Space Center.
Specifically, the conference will focus on the goals and strategies, the next steps, and the new technologies, new jobs, and new industries it will create, the White House said. Conference topics will include the implications of the new strategy for Florida, the nation, and our ultimate activities in space.
The proposed plan for NASA, which includes cutting the Constellation program to return to the Moon, has drawn extreme reactions — both praise and harsh criticism since first announced on Feb. 1, 2010. Most agreed, however, that the plan was short on details as to destinations and how we might get there.
After the Augustine Commission found that Constellation program was “fundamentally un-executable,” Obama’s new plan cancels the Ares rockets but add $6 billion for NASA over the next five years.
“This funding will help us achieve our boldest aspirations in space,” the White House said in the press release. “The President’s ambitious new strategy pushes the frontiers of innovation to set NASA on a more dynamic, flexible, and sustainable trajectory that can propel us on a new journey of innovation and discovery.”
But former astronaut Leroy Chiao, a member of the Augustine Commission said he was surprised Constellation was cut.
“I didn’t foresee the recent announcement of the cancellation of the NASA Orion crew exploration vehicle (CEV),” Chiao wrote in his blog,“the commercial option was for LEO access, not exploration. I expected that CEV, along with either a heavy lift vehicle, or a man-rated expendable launcher would serve as a complimentary system to commercial LEO efforts. Details of the US plans for the future of NASA human spaceflight remain to be revealed, but I remain cautiously optimistic. Sometimes it takes dramatic change, even temporary chaos, to affect the possibility of a quantum jump in improvement.”
There’s been much discussion about if this new “plan” means the end of human spaceflight as we know it. It might. But do we want to keep going with the status quo, or go in new directions? Hopefully the April 15 conference will provide the details everyone is craving. Change is hard, and certainly, not everyone will be satisfied.
As with last week’s Universe Puzzle, something that cannot be answered by five minutes spent googling, a puzzle that requires you to cudgel your brains a bit, and do some lateral thinking. This is a puzzle on a “Universal” topic – astronomy and astronomers; space, satellites, missions, and astronauts; planets, moons, telescopes, and so on.
What’s the next number in the sequence? 401, 172, 85.2
There are no prizes for the first correct answer – there may not even be just one correct answer – posted as a comment (the judge’s decision – mine! – will be final), but I do hope that you’ll have lots of fun.
Post your guesses in the comments section, and check back on Wednesday at this same post to find the answer. Good luck!
UPDATE: Answer has been posted below.
42.5 is the answer; it’s the mean orbital period of Io, in hours; the first three members of the sequence are the mean orbital periods of Callisto, Ganymede, and Europa (source)
NGC 4490/4485 – T. Grossman, D. Hager and R. Johnson
Way out yonder some 40 to 50 million light years away in the constellation of Canes Venetici is a pair of interacting galaxies sometimes referred to as “The Cocoon”. These two mis-shaped blobs of star stuff have already made their closest approach to each other and are now parting ways. Between them stretches a trail of stars that spans some 24,000 light years as they face each other showing off their numerous star-forming regions. But where there is life… There is death. Let’s put our finger right on the pulse of a supernova. Continue reading “Taking The Pulse Of A Supernova – NGC 4490”
Short on fuel, but good at astrophysics? It is possible to tour the solar system on less than 30 Altairian dollars a day by using the Interplanetary Transport Network (ITN).
The ITN is based on gravity assist manoeuvres and low energy transfer orbits around and between Lagrange points. Using the ITN, it is theoretically possible to tour the solar system with an exceedingly economic use of fuel as long as you have an abundance of patience and don’t mind taking an often circuitous route to your destination.
If you imagine the whole solar system as a rubber sheet which is warped by gravity wells, then the planets are really just small depressions of different depths pressed into the sides the Sun’s overarching gravity well.
What’s important to this story is that the edges of those small depressions are nearly flat with respect to the otherwise steep slopes created by the Sun and the planets. It takes a lot less energy to move around on these flat edges, than it does trying to climb straight up the steep slopes.
The flat edge that is present around the Earth’s gravity well is land marked by Lagrange point 1 (or L1) lying directly between the Sun and the Earth – and Lagrange point 2 (L2) on the opposite side of the Earth directly away from the Sun.
It’s possible for a spacecraft to orbit a Lagrange point and be carried around the Sun with very little expenditure of energy. It’s because you are essentially riding the bow wave of the Earth as it orbits the Sun – so you are carried the Sun at the same orbital speed as the Earth (30 kilometres a second) without having to burn a lot of fuel in the process.
Also the Lagrange points represent junction points to enable low energy transfer between different planetary orbits. As though the solar system’s space-time curvature makes for a giant skateboard park, it’s possible to step off L1 and follow a trajectory down to Venus – or you can coast across the flat edge of Earth’s gravity well for about 3 million kilometres to L2 and then step off on a long winding path to the L1 of Mars. Here you might rest again before perhaps shuffling across to Mars’ L2 and then on to Jupiter.
Mathematical analysis of the gravitational interactions between three or four bodies (say, your spacecraft, the Earth and the Sun – and then add Mars too) – is complex and has some similarities with chaos theory. But such an analysis can identify interconnecting pathways right across the solar system, which ITN proponents refer to as ‘tubes’.
The image on the left (Credit: American Scientist) shows an ITN ‘tube’ approaching Earth’s L2. At this point a cosmic hitchhiker can either double back on a trajectory towards Venus (red line), stay in orbit around L2 and tag along with Earth– or continue on through (blue line), perhaps entering another ITN tube on the way to Mars. The image on right shows a tongue-in-cheek depiction of the ITN tube network (Credit: NASA).
ITN principles have been adopted by a number of spacecraft missions to conserve fuel. Edward Belbruno proposed a low energy lunar transfer to get the Japanese probe Hiten into lunar orbit in 1991 despite it only having 10% of the fuel required for a traditional trans-lunar insertion trajectory. The manoeuvre was successful, although travel time to the Moon was five months instead of the traditional three days. NASA’s Genesis mission and the ESA’s SMART-1 are also considered to have used low energy ITN-like trajectories.
So impoverished hitchhikers, maybe you can still have that grand tour of planets by using the ITN – but make sure you pack a towel, it will be a very long trip.
(Recommended reading: Ross, S.D. (2006) The interplanetary transport network. American Scientist 94(3), 230–237.)
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Classify this one under the same nonsense as the “Bigfoot on Mars” the wooden plank on Mars, or perhaps even the “Face on Mars.” Just an optical illusions, folks from a very, very zoomed in image from the Mars rovers. The Sun newspaper seemingly started this foolishness on what must have been a slow news day.
Doug Ellison from Unmanned Spaceflight put together this “poster” about the gorilla (Click image for larger version):
And the folks at Image Shack show the real dimensions of the rock:
The original image has been around awhile. It was taken by the Opportunity rover back on sol 87 in 2004. Click here to see the original image. Can you see any gorillas? I’m sure if you look really close and zoom in and distort any of the rocks you can see whatever you fancy.
Garver and Bolden after they were sworn into office. Credit: NASA
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Several news sources reported Thursday that NASA Administrator Charlie Bolden had asked senior managers to come up with an alternate plan for the newly proposed NASA budget after members of Congress indicated they wanted to reject a White House proposal to cancel the Constellation program and hire private companies to bring astronauts to the ISS. But today, Bolden issued a memo saying there is no “Plan B” and that he only asked two agency directors to help develop an accelerated plan for research and development on a heavy lift launch vehicle. The lack of heavy lift capability is one of the big sticking points for many on the new plan.
“I have not asked anyone to develop an alternative to that budget and plan,” Bolden wrote, “and I don’t want anybody to do so. Rather, I have asked – and am asking – for input on how the exceptional talents and capabilities we have developed in our organization can best be applied going forward to advance the elements of our new plan.”
The proposed plan for NASA seemingly has divided supporters of the space program. Daily, there are reports on new plans being formulated by Florida legislators to try to extend the shuttle program going or keep Constellation alive. But Deputy Administrator Lori Garver said yesterday that the option for extending the shuttles has come and gone. “I was told by the entire shuttle NASA folks that, in fact, that time had come and gone. It was not an issue of money at that point, it was an issue of second-tier suppliers, there would be at least a two-year gap between our last flight and the next one, et cetera.” That situation, she said, was a result a previous policies: “We inherited what we inherited.”
Garver told a Capitol Hill audience on March 4 that she empathized with those seeking to save Constellation, but said continuing Constellation and pursuing the president’s priorities for NASA would cost $5 billion more per year than the roughly $19 billion a year the White House has budgeted for the space agency through the end of Obama’s first term.
“Think of it this way,” she said. “If you are focused on getting the Constellation budget continued in the future — and I harbor no ill will against those of you who do … but if Constellation is put back in the budget without that $5 billion-a-year increase, where will we cut the budget?” she asked.
In Bolden’s memo, he also talked about those who don’t agree with the proposed plan for NASA: “I find great comfort in knowing that President Obama has seen fit to put his faith in us to develop a game-changing strategy in our four mission areas, and that he has given us a $6 billion plus up on our FY10 budget as a show of support and trust. I fully believe in the plan that this budget has allowed us to set out for NASA’s road ahead, and unlike many of our detractors, I do believe it will very likely allow us to reach exploration destinations sooner and more efficiently than we would have been able to while we were struggling to develop the Constellation Program.”
Where will this all end up? Only time will tell. If nothing else, Obama’s plan for NASA has stirred deep feelings for the space program.
A mosaic image of Phobos composed by 53 pictures. Credits: ESA/ DLR (S. Semm, M. Wählisch, K.Willner)/ FU Berlin (G. Neukum)
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Back in the 1950s and 1960s, there was some speculation that Mars’ moon Phobos could possibly be hollow due to the its unusual orbital characteristics. While scientists now agree that the moon is very likely not hollow, vast caverns may exist within the moon, and it might be a porous body instead of solid. The Mars Express spacecraft made a close flyby of Phobos on Wednesday to help provide more data on the interior of Phobos, and all indications are the event was a big success. The spacecraft skimmed smoothly over the odd-shaped moon at just 67 km, the closest any manmade object has ever been. No images were taken from this flyby. Instead all the instruments were turned off so that ground stations could listen for a pure radio signal of how Phobos “tugged” on the spacecraft. Scientists say the data collected could help unlock the origin of Phobos and other ‘second generation’ moons.
“Phobos is probably a second-generation Solar System object,” said Martin Pätzold, Universitat Koln, Cologne, Germany, and Principal Investigator of the Mars Radio Science (MaRS) experiment. Second generation means that it coalesced in orbit after Mars formed, rather than forming at the same time out of the same birth cloud as the Red Planet. There are other moons around other planets where this is thought to have been the case too, such as Amalthea around Jupiter.
Previous flybys of Phobos have shown that it is not dense enough to be solid all the way through. Instead, it must be 25-35% porous. This has led planetary scientists to believe that it is little more than a ‘rubble pile’ circling Mars. Such a rubble pile would be composed of blocks both large and small resting together, with possibly large spaces between them where they do not fit easily together.
The March 3rd flyby was close enough to give scientists the best data yet about the gravitational field of Phobos.
The radio waves travel at the speed of light and took 6 minutes 34 seconds to travel from Earth to the spacecraft on Wednesday night, and by analyzing the data on Phobos’ gravity field, scientists should be able to estimate of the density variation across the moon and detect just how much of Phobos’ interior is likely to be composed of voids.
This flyby was just one of a campaign of 12 Mars Express flybys taking place in February and March 2010. For the previous two, the radar was working, attempting to probe beneath the surface of the moon, looking for reflections from structures inside. In the coming flybys, the Mars Express camera will take over, providing high resolution pictures of the moon’s surface.
Here are some tsunami wave pictures. You can make any of these images into your computer desktop background. Just click on an image to enlarge it, and then right-click and choose “Set as Desktop Background”.
Here’s an image from space shortly after the Boxing Day 2004 earthquake that generated the terrible tsunami. You can see the large waves rippling in the ocean just off the coast of Sumatra, Indonesia.
This photo from space shows the devastation that occurred after the December 2004 tsunami struck Little Andaman Island, off the coast of India. You can see how a village was completely wiped out.
Here’s an image of Sumatra in Indonesia, after the 2004 tsunami struck the coast, wiping out a huge portion of the coastal forest. After the tsunami struck, the entire coast of the island looks like it was cleared back several hundred meters.
This photograph shows damage from the 2004 tsunami off the west coast of Sumatra.
Here’s an image of Phuket, an island off the coast of Thailand. It’s famous for its warm water and beautiful beaches, but it was slammed with a powerful tsunami in 2004, just an hour after the earthquake that generated the wave.
