David Lanz & Paul Speer – Lento984
An evening pause: From their Natural States music video album released 1985.
Hat tip Diane Zimmerman.
Confirmed: Ryugu is a rubble pile
Click for source paper [pdf].
At a special session today dedicated to results from the Hayabusa-2 probe to the asteroid Ryugu at the 50th Lunar and Planetary Science Conference in Texas, scientists confirmed from numerous data and images that the asteroid has a low density, is covered with boulders and pebbles, is very porous, and is thus a rubble pile that is held together by gravity, barely.
From their lead presentation [pdf]:
The estimated total porosity is even higher than that of rubble-pile asteroid Itokawa (44 ± 4%), indicating that asteroid Ryugu is also a rubble pile. This is consistent with a theory arguing that all Solar System bodies with diameter of ~1 km should be rubble piles and might have formed from reaccumulation of fragments generated by catastrophic disruption events of ~100-km sized parent bodies.
They also posit that the asteroid’s diamond shape is caused by the asteroid’s 3.5 hour rotation, which causes its weak rubble pile structure to be easily pulled to the equator, and then outward.
Another paper [pdf] did crater counts, and found that there are fewer large craters than one would expect.
The density of large craters (D>100 m) on Ryugu is lower than the empirical saturation level and its slope is steeper than that of the saturated distribution, suggesting that craters larger than 100 m are not saturated and the size distribution reflects the crater production function. However, craters smaller than 100 m are significantly under-saturated, suggesting that some crater erasure processes such as seismic shaking and armoring effect are active on the Ryugu surface. Based on cratering chronology model for the main belt, the surface age of Ryugu is estimated to be 5–200 [million years] from the size–frequency distribution of craters larger than 100 m.
In other words, this rubble pile is constantly being shaken by its rotation and time and later impacts, which steadily rewrites the surface.
If this asteroid was headed to Earth, I imagine the only safe solution to prevent disaster would be to slowly and gently deflect it so it only flies past. To do this will require an arrival far in advance of the schedule impact, to give time for the deflection process to work.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Snow on Mars?
Click to see full image.
At today’s presentations at the 50th Lunar and Planetary Science Conference in Texas, scientists showed images and data [pdf] suggesting that many of the Martian gullies found on cliff faces are formed when the dust layer protecting underlying snow gets blown away and the exposed snow/ice then melts.
The image on the right was taken by the high resolution camera of Mars Reconnaissance Orbiter (MRO) in 2009, and has been cropped to post here. The white streaks are what they suggest is exposed ice/snow.
Test drone maps ice cave in Iceland
Engineers have tested a prototype lidar-equipped drone by flying it through a lava tube in Iceland and using it to automatically map the tube.
While a cave-exploring drone on Earth may use propellers, free-flying spacecraft exploring caves on the Moon, where there is practically no atmosphere, or in the thin air of high altitude lava tubes on Mars’ giant volcanoes, would have to use small thrusters. The mission of the terrestrial drone deployed at the Lofthellir Ice Cave focused on validating the idea of using a drone-equipped LiDAR to safely navigate and accurately map rock and ice inside a dark lava tube in the absence of GPS or any prior map.
Under a research contract with NASA, Astrobotic has developed a custom navigation software product, known as AstroNav, to give drones and small free-flying spacecraft the ability to autonomously explore and map subterranean environments. AstroNav employs both stereo vision and LiDAR, works without GPS or previously stored maps, and can operate in real-time while a novel environment is explored at a high rate of speed.
…”The Astrobotic drone and LiDAR performed exactly as we had hoped, and was able to help us map the Lofthellir Lava Tube in 3D within minutes” says Lee. “We now have a highly accurate model of the shape and dimensions of the cave, and of the configuration of its many rocky and icy features, such as rock falls, ice columns, and micro-glaciers.”
The concept is an excellent one, especially for exploring the caves and pits of Mars. This test however only checked out the lidar. A drone that could do this on either Mars or the Moon does not yet exist.
I have posted their video of the flight below the fold.
Note: Thanks to reader Eddie Willers for noting that I mistakenly located this research in Greenland, not Iceland. Post now corrected.
» Read more
Now available in hardback and paperback as well as ebook!
From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.
“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of the Mars Society.
All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. All editions can also be purchased direct from the ebook publisher, ebookit, in which case you don't support the big tech companies and the author gets a bigger cut much sooner.
Autographed printed copies are also available at discount directly from the author (hardback $29.95; paperback $14.95; Shipping cost for either: $6.00). Just send an email to zimmerman @ nasw dot org.
A rock on Bennu
Click for full image (which is rotated 180 degrees).
Cool image time! The OSIRIS-REx science team today released a close-up image of the surface of the asteroid Bennu. The image on the right is a cropped and rotated section of that image, focusing on the image’s star, its largest rock.
The boulders on Bennu’s surface sport a variety of surface textures, from smooth, to hummocky, striated, and crumbly “cauliflower” in nature. The large boulder in the image center is ~92 ft (~28 m) across and has a somewhat round shape, though many smaller boulders surrounding it are very angular. Some of these appear to be fragments that may have disaggregated from the central boulder and display layering effects that may reflect some of the properties of their mineral composition. Other boulders show signs of surface exfoliation and fractures that may have been caused by impacts, mechanical weathering, and other forms of rock breakdown active on Bennu’s surface.
The image was taken from less than a mile away, and shows a spot near the asteroid’s south pole.
Why the larger boulder has a rounded look, but the pebbles around it are jagged, is a puzzle.
The science team also revealed today that they have detected plumes of particles being released from the asteroid’s surface. They have also found Bennu to present them with the same problem faced by the Hayabusa-2 team at Ryugu: The asteroid is far rougher than expected.
The higher-than-expected density of boulders means that the mission’s plans for sample collection, also known as Touch-and-Go (TAG), need to be adjusted. The original mission design was based on a sample site that is hazard-free, with an 82-foot (25-meter) radius. However, because of the unexpectedly rugged terrain, the team hasn’t been able to identify a site of that size on Bennu. Instead, it has begun to identify candidate sites that are much smaller in radius.
Hayabusa-2 schedules explosion on Ryugu
The Hayabusa-2 science team has scheduled April 5 for when it will use the spacecraft to fire an explosive device into Ryugu to create a crater and debris cloud.
The probe is scheduled to detach a device loaded with explosives some 500 meters away from Ryugu. The device will set off the explosives using a timer some 40 minutes later and launch a copper “impactor” weighing about 2 kilograms into the asteroid’s surface.
The target point is several hundreds of meters away from where the space probe first touched down. The mission will require the spacecraft to move quickly to the other side of the asteroid so it won’t get hit by flying shards from the blast. A detached camera will shoot the moment of impact.
JAXA will analyze the size and shape of the crater, and how rocks fly off in a bid to collect underground samples for possible clues to the origin of the solar system.
This is different than the touchdown last month, as the spacecraft itself will not get close to the asteroid.
Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel, can be purchased as an ebook everywhere for only $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from my ebook publisher, ebookit.
If you buy it from ebookit you don't support the big oppressive tech companies and I get a bigger cut much sooner.
Winner of the 2003 Eugene M. Emme Award of the American Astronautical Society.
"Leaving Earth is one of the best and certainly the most comprehensive summary of our drive into space that I have ever read. It will be invaluable to future scholars because it will tell them how the next chapter of human history opened." -- Arthur C. Clarke
Cost for Mars 2020 rover up 15%
Because of cost overruns in building three instruments for the Mars 2020 rover, its total budget will rise by 15%, forcing NASA to trim budgets elsewhere in its planetary program.
There are small efficiencies to be gained internally in Mars 2020, Glaze says, which, like its predecessor Curiosity, is being developed by NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. Some work can be postponed, some timelines tightened; the end of the Opportunity rover, which expired late last year on Mars, will help. But it is expected the costs will largely be borne by trims to the operations of existing Mars missions and funds the agency sets aside for future missions, including the return of the rock samples that Mars 2020 will collect. “We tried to spread it so no one is feeling all of the pain,” Glaze says.
For a government program costing almost $2.5 billion, this overage is remarkably small. What is more significant is that the rover appears on schedule for launch in July 2020.
Pink Floyd – Us and Them
A evening pause: Recorded live 1988. The song’s general hostility to war is an example of one of the greatest hallmarks of civilization. To make believe however that war is never necessary is to bow to those things that wish to destroy civilization, which is a most delicate thing.
Hat tip Mike Nelson.
PINK FLOYD – us and them – live delicate sound of thunder 1988 – YouTube from STEVE MCLEAN on Vimeo.
Mars likely has many large and extensive cave systems
More caves on Mars! This week the Lunar and Planetary Institute and the Johnson Space Center are jointly holding the 50th Lunar and Planetary Science Conference in Texas. I have been going over the program, and will be posting reviews of some of the more interesting results all this week.
We begin with caves, which should not be surprising to my regular readers. As a caver who also knows their value for future space colonists, I am always attracted to new discoveries of cave passages on other worlds. Today’s however is a doozy.
The image to the right is of Mamers Valles on Mars, what scientists have dubbed a fretted valley, a common feature in the transition zone between the low altitude northern plains and the southern highlands. It comes from a paper [pdf] with the typically unexciting scientific title, “Fretted channels and closed depressions in northern Arabia Terra, Mars: Origins and implications for subsurface hydrologic activity.”
What the scientists really means here is that their research strongly suggests that Mars has a very large and very extensive number of underground drainage systems, which have caused collapses on the surface that often resemble meandering river canyons, such as seen above. As they explain:
» Read more
DARPA’s satellite servicing mission adrift
Capitalism in space? DARPA’s program to test a satellite servicing mission appears in serious and complex trouble with the termination by Maxar (previously called SSL) of its contract to build the structure, or “bus”, of the robot.
What makes this more complicated is that the company building the actual servicing payload is continuing its work.
While Maxar will no longer be providing the satellite bus, work on the servicing payload continues. Among the companies involved in that effort is Praxis, a company handling planning for mission operations of the RSGS servicing system, such as how the system will safely grapple the target satellite. “For our day-to-day operations, that hasn’t really affected us. We’re pretty far along on the payload development,” said Tony Marzi, general manager of Praxis, during a presentation at the MIT New Space Age Conference at the Massachusetts Institute of Technology here March 15.
DARPA is thus calling for proposals to launch this payload.
The irony here is that this DARPA project was under criticism from the start, even to the point that a competing satellite servicing company, Orbital ATK, sued the agency. That company, now part of Northrop Grumman, was building its own privately funded servicing robot, and considered DARPA’s effort to be unfair in that it provided direct government subsidies to its competitors.
While Orbital ATK lost its suit, it now appears it has won the competition — assuming it eventually launches its own mission.
OneWeb raises $1.25 billion
Capitalism in space: Following the launch of the first six satellites for its 650 satellite constellation to provide worldwide internet services, OneWeb today announced that it has successfully raised $1.25 billion in new investment capital.
…it has secured its largest fundraising round to date with the successful raise of $1.25 billion in new capital. This brings the total funds raised to $3.4 billion. This round was led by SoftBank Group Corp., Grupo Salinas, Qualcomm Technologies Inc., and the Government of Rwanda.
The new funds, following the successful first launch of OneWeb’s satellites, enable the company to accelerate the development of the first truly global communications network by 2021.
…OneWeb’s satellites, produced through its joint venture with Airbus doing business as “OneWeb Satellites”, will ramp-up production this spring at its new, state-of-the-art manufacturing facility in Exploration Park, Florida. Following the company’s successful launch of satellites on February 27th, OneWeb will embark on the largest satellite launch campaign in history. Starting in Q4, OneWeb will begin monthly launches of more than 30 satellites at a time, creating an initial constellation of 650 satellites to enable full global coverage. After this first phase, OneWeb will add more satellites to its constellation to meet growing demands.
This puts OneWeb significantly ahead of everyone else, including SpaceX, in the race to launch the first space-based system for providing internet services. Their planned launch pace also illustrates why there is a flood of new smallsat rocket companies. They, and others, have a clear need for launch services, which presently cannot be provided by the existing launch companies.
First SpaceX Starship Hopper tests this week?
Capitalism in space: According to this news story on Sunday, SpaceX could attempt its first Starship Hopper tests this week.
A sheriff hand-delivered road closure notices to residents on Friday, according to a local resident. The document warned locals that SpaceX will “conduct testing” as soon as Monday, March 18.
The article also cites a flurry of tweets about the hopper that Elon Musk made on Sunday. Unfortunately, Musk’s tweets do not say anything about tests this week.
Regardless, it appears that SpaceX might actually be close to beating the schedule it announced for these tests back in November, when Musk said they were aiming for tests in June. If so, this would be a remarkable achievement, one that is almost unheard of in the aerospace launch industry.
New Zealand threatens prison for publishing material showing this week’s shootings
They’re coming for you next: Even as the New Zealand government has issued threats of ten year prison terms for sharing or even possessing the video’s from the mosque shooting this week, the large internet corporations are moving in to support this censorship.
Terrorist Brenton Tarrant used Facebook Live to broadcast the first 17 minutes of his attack on the Al Noor Mosque in Christchurch, New Zealand at approximately 1:40 p.m. on Friday – the first of two mosque attacks which left 50 dead and 50 injured.
Copies of Tarrant’s livestream, along with his lengthy manifesto, began to rapidly circulate on various file hosting sites following the attack, which as we noted Friday – were quickly scrubbed from mainstream platforms such as Facebook, YouTube, Twitter and Scribd. YouTube has gone so far as to intentionally disable search filters so that people cannot find Christchurch shooting materials – including footage of suspected multiple shooters as well as the arrest of Tarrant and other suspects.
On Saturday, journalist Nick Monroe reported that New Zealand police have warned citizens that they face imprisonment for distributing the video, while popular New Zealand Facebook group Wellington Live notes that “NZ police would like to remind the public that it is an offence to share an objectional publication which includes the horrific video from yesterday’s attack. If you see this video, report it immediately. Do not download it. Do not share it. If you are found to have a copy of the video or to have shared it, you face fines & potential imprisonment.”
Distributing this killer’s video to me seems more than odious, but having the government and these internet giants team up to censor it, while also censoring distribution of his manifesto, which showed clearly that this madman was no right wing Trump supporter, is even more unconscionable. Such censorship only serves to encourage further such attacks, as it shows that future attackers can have far more influence and impact than merely killing fifty people. They can shut down free speech and western civilization worldwide.
This censorship also allows the liberal Democratic press to continue to push the lie that this madman was instigated by Trump, without no facts to challenge it.
That dark age sure is coming, and it looks like it is getting here faster every day.
ULA’s Delta 4 rocket launches Air Force communications satellite
Capitalsm in space: ULA yesterday used its Delta 4 rocket to successfully place in orbit an Air Force communications satellite.
This is one of the last launches of the the Delta 4 member in the Delta rocket family.
The mission marked the next-to-last flight of the Delta 4 rocket variant with a single first stage core — known as the Delta 4-Medium — as ULA begins retiring segments of its launcher family in preparation for the debut of the new Vulcan booster, which the company says will be less expensive than the existing Atlas and Delta fleet.
Gary Wentz, ULA’s vice president of government and commercial programs, said the company’s decision in 2014 to retire the Delta 4-Medium was intended to reduce the company’s costs. “We started looking at the products that we were providing, and found that maintaining these two families of launch vehicles, both the Delta and the Atlas, through this period decreased our flight rate, and therefore increased our costs,” Wentz said. “That really drove it, based on the competitive industry we’re in, trying to maximize our competitiveness.”
The Delta 4-Medium family provides the same range of lift capability as the less expensive Atlas 5 rocket. The Delta 4-Heavy, which will remain operational through at least the early-to-mid-2020s, uses three Delta 4 first stage cores bolted together to haul heavier payloads to orbit than any of the Atlas 5 configurations.
The leaders in the 2019 launch race:
3 SpaceX
3 China
2 Europe (Arianespace)
2 Russia
2 ULA
In the national rankings, the U.S. has now widened its lead on China to 5 to 3.
Note that two different American companies are matching the launch numbers of three other whole countries. This I think illustrates well the power of freedom and competition. Rather than have a single nationalized rocket system (as was attempted in the 2000s when Boeing and Lockheed Martin created ULA, then the only American rocket company), the U.S. has transitioned back to its roots, allowing freedom to produce multiple companies competing for both private and government business. This has reduced costs, encouraged innovation, and ended up producing more jobs and wealth.
Timestorm Films – South Pole: Night in Antarctica
An evening pause: For those, like myself, who have never seen the aurora.
Hat tip Steve Golson.
SOUTH POLE | NIGHT IN ANTARCTICA from Martin Heck | Timestorm Films on Vimeo.
On the radio
I will be visiting with Robert Pratt today at 6:05 pm (Eastern) for an hour on his Texas radio show, Pratt on Texas, aired on 790-AM KFYO in Lubbock, 1470-AM KYYW in Abilene, and 1290-AM KWFS in Wichita Falls.
I expect we will be discussing SLS and the effort of the corrupt culture of Washington to keep that unproductive boondoggle alive.
The Washington Empire strikes back!
In response to the revelation earlier this week by NASA administrator Jim Bridenstine that the agency is considering replacing SLS with commercial rockets for Orion’s first unmanned lunar test mission in June 2020, the swamp in Washington quickly rallied to SLS’s defense.
Not surprisingly, porkmeister Senator Richard Shelby (R-Alabama) led the charge:
“While I agree that the delay in the SLS launch schedule is unacceptable, I firmly believe that SLS should launch the Orion,” Sen. Richard Shelby (R-Ala.) said in a statement to SpaceNews.
This was followed by statements from industry groups and other lawmakers, all supporting SLS. Next came Bridenstine himself, who emphasized his strong support of SLS at a conference yesterday, then issued a memo to NASA employees reiterating that support.
As far as I can tell, the only way SLS will eventually die is when private companies begin doing things that SLS is designed for, for less money and faster, and for profit. And that won’t happen if this Washington swamp has its say. Rather than see an American success, these cronies have made it clear in the past decade that they will work to squelch any such success if poses any threat to their boondoggles. And it appears now that they are moving to block Bridenstine’s suggestion for that first Orion flight.
Whether this new big government campaign against private enterprise succeeds however is not clear.
» Read more
Rogozin: Russia and U.S. to use both countrys’ manned capsules to ISS
According to statements made today by Roscosmos head Dmitri Rogozin, Russia and the United States now plan to send their astronauts to ISS using both the Russian and American capsules.
“We agreed with the NASA leadership to preserve our agreements and principles of cooperation. Astronauts will fly on board Soyuz, and we will use US spacecraft,” he said, adding that US spacecraft will need to get certification first.
According to the Roscosmos head, this will create an alternative in manned space missions to the International Space Station.
This suggests that once the U.S. commercial capsules are operational the two countries will return to the situation that existed when the shuttle was flying, with Americans sometimes flying on Russian spacecraft and Russians sometimes flying on American spacecraft. Under that set-up however, there was no direct payment by the U.S. for its seats on those Russian spacecraft, since it was a straight embargo deal.
Will this be the case now? We shall see. NASA for the past two decades has increasingly worked to keep the Russian space effort operating, sometimes even to the detriment of American efforts.
If Russia no longer gets money from the U.S. for its space flights it simply might not be able to afford to fly. We really won’t need them, but for a number of reasons we might decide to pay them to keep them in the game, both from a foreign policy perspective as well as some underhanded motives that are divorced from considerations of the national interest.
Unfortunately, separating these two issues has become increasingly difficult, especially because of the spreading corruption that is taking over the Washington establishment. This establishment more and more cares little for this country. Instead, it puts its own interests and power first, often in direct violation of the Constitution and the fundamental principles that founded the United States. Under these conditions that establishment might decide it is better to help the Russians, even if it hurts America and its citizens.
A pond on Bennu
Click for full resolution.
The OSIRIS-REx science team has released new high resolution images of one particular area on Bennu’s northern hemisphere. The image on the right, cropped and reduced to post here, shows what they label a “pond of regolith,” seen as the relatively smooth area in the upper left.
This is not literally a pond, but instead is a low-lying spot where smaller particles have settled over time, producing a flattish area that looks, and in some ways, resembles a pond or puddle, only in this case the material isn’t water but fine-grained dust or pebbles.
On March 19 the science team will be presenting their initial results at a special session at the 50th Lunar and Planetary Science Conference in Texas. That same day they will hold a press conference summarizing the most interesting aspects of those results. Stay tuned.
Chinese lunar rover and lander enter their third lunar night
The Chinese lunar rover Yutu-2 and its lander Chang’e-4 have gone into hibernation as they enter their third lunar night on the far side of the Moon.
According to Chinese news reports, both spacecraft have now exceeded their nominal lifespan.
With all systems and payloads operating well, the Yutu-2 team will continue roving and science data collection on lunar day 4 of the Chang’e-4 mission, according to a [Chinese] announcement.
Yutu-2 added 43 meters to its overall drive distance in its third day of activities, continuing a path to the northwest of the landing site, which was recently named ‘Statio Tianhe’ by the International Astronomical Union. The rover just covered seven meters between waking for lunar day 3 on Feb. 28 and Mar. 3, during which time it navigated carefully toward a 20 centimeter diameter rock in order to analyze the specimen with an infrared and visible light spectrometer to determine its origin.
I am struck by how tentative the Chinese and their rover appear. The first Russian lunar rover, Luna 17, traveled 6.5 miles in eleven months. The second, Luna 21, traveled 23 miles in four months. At the pace Yutu-2 is setting, it will not come close to these mileages. Moreover, my impression of Chinese space technology in the past decade has been that it is quite robust. This tentativeness thus surprises me. Maybe because this is a government project they are simply covering their butts should something go wrong, and thus making believe the rover is more delicate than it really is.
As Scotty on Star Trek once said, “Always under predict, then over perform.” We might be seeing that pattern here.