Tag: engineering

China loses contact with one of two lunar cubesats

8:59 am

China has lost contact with one of the two test cubesats that were launched to the moon with their Queqiao Chang’e-4 communications satellite.

Though they continue to receive telemetry from one cubesat, without the second they will be unable to do the radio astronomy and interferometry experiments planned.

The interferometry experiments would have seen the observations made simultaneously by the DSLWP/Longjiang microsatellites to be combined. The test would be verification of technology for a constellation of small, low-frequency radio astronomy satellites that would emulate a telescope with a size equal to the maximum separation between the satellites.

The Chang’e-4 mission could however see some interferometry tests carried out, with Queqiao carrying the Netherlands-China Low-frequency Explorer (NCLE) astronomy instrument, and a Low Frequency Spectrometer (LFS) on the Chang’e-4 lander, which is expected to launch in November or December, following testing of Queqiao.

All is not lost. The cubesat that still functions has a camera, built in Saudi Arabia, and if it takes and successfully transmits any pictures this will be a cubesat landmark, the first interplanetary images ever taken by a cubesat.

Meanwhile, Queqiao Change’-4 is working as expected, laying the ground work for the launch of the Chang’e-4 lander later this year.

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NASA reconfiguring future SLS planning

2:24 pm

Link here. This is a long (4 parts) and detailed overview of the changing state of the SLS system and its future missions. As it notes right at the start,

NASA has started updating plans and schedules for additional SLS Block 1 launches in the early 2020s after Washington added federal budget money for a second Mobile Launcher (ML) platform and umbilical tower in late March.

Construction of a new Mobile Launcher frees the first ML from a three-year long downtime for teardown and reassembly after the first SLS launch of Exploration Mission-1 (EM-1), currently projected for mid-2020. Instead of being retired after one launch, the Block 1 configuration could fly multiple times.

With two mobile launches (costing almost a billion to build), NASA has more flexibility (assuming it gets full funding). It can now fly both the smaller Block 1 configuration of SLS multiple times without delaying the first launch of the planned more powerful Block 2 version expected to come later.

The article discusses in great detail the possible variations in design and scheduling for the first unmanned mission, the Europa mission, the first manned mission, and possible missions beyond, all of which are based on Congress’s continued blank check support for this very expensive and very questionable program.

Sadly, it increasingly appears that Congress is going to throw a lot of money at this program. SLS looks like it is going to fly several times, and maybe more. It will likely send Europa Clipper to Jupiter, and later astronauts on a stunt mission around the Moon. Later, the Washington cartel of big aerospace companies, NASA, Congress, and our international partners in Europe and Russia are gearing up to get LOP-G funded as well, with SLS the vehicle to launch and supply it.

All of this will cost a lot, take forever, and not make the future exploration of the solar system possible in the slightest. None of that matters however. Congress wants it, and Congress being corrupt and irresponsible is going to get it.

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Rocket Lab announces new launch date

9:33 am

Capitalism in space: Rocket Lab has announced a new launch window for the first operational launch of its Electron rocket, beginning on June 23 for fourteen days.

Those dates are based on New Zealand time. If they launch at the very beginning of this window it will occur on June 22 in U.S.

The two month delay was caused by a problem with a “motor control unit.” This has been replaced. In the interim they have also added two more commercial payloads to the rocket.

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China launches two test cubesats to the Moon

10:02 am

The launch this week of a Chinese communications relay satellite to be used for its Chang’e-4 lunar lander also included the launch of two test cubesats designed to test such satellites in interplanetary space.

One of the two Longjiang (‘dragon river’) microsatellites that launched with Queqiao but set to operate together in lunar orbit, carries an optical microcamera (Arabic) developed by the King Abdulaziz City for Science and Technology (KACST) of Saudi Arabia.

The instrument weighs around 630 g and is capable providing images of the Moon with a resolution of 38 m per pixel at a perilune of 300 km and 88 m per pixel at the expected apolune of 9, 000 km away the lunar surface.

The Longjiang-1 and -2 satellites, developed by Harbin Institute of Technology (HIT) in Northeast China, will test low-frequency astronomy and space-based interferometry in lunar orbit. However, they also carry amateur radio payloads, meaning amateurs can send commands to take and download an image of the Moon using the KACST camera.

It seems that China is trying to compete with the U.S. in the development of interplanetary cubesats. The inclusion of an instrument developed in Saudi Arabia is also another indication that the new colonial movement in space continues to pick up steam.

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Can we trust any deal with North Korea?

9:48 am

Link here. The article, from the science journal Nature, is an interview with a South Korean nuclear expert who is very skeptical of any claims by North Korea that it has dismantled its nuclear program.

This skepticism seems reasonable to me. Consider the history. The Clinton administration signed a deal with North Korea (very similar in many ways with Obama’s Iran nuclear deal) that was supposed to prevent North Korea from getting the bomb. Instead, all it did was allow us to make believe it wasn’t happening, even as North Korea developed the technology and eventually completed several underground tests of nuclear bombs.

We shall see if Trump allows himself to get fooled, like Clinton. Right now, the indications are no. At the same time, it pays to be as skeptical of any politician as this South Korean nuclear expert is of North Korea. None of these power-hungry politicians can be trusted, even Trump. When the general public makes the mistake of trusting them it always gets screwed.

Update: Trump has canceled the summit with North Korea.

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Mars rover update: May 23, 2018

3:35 pm

Summary: Curiosity drives down off of Vera Rubin Ridge to do drilling in lower Murray Formation geology unit, while Opportunity continues to puzzle over the formation process that created Perseverance Valley in the rim of Endeavour Crater.

For a list of past updates beginning in July 2016, see my February 8, 2018 update.

Curiosity

Curiosity's travels on and off Vera Rubin Ridge

For the overall context of Curiosity’s travels, see Pinpointing Curiosity’s location in Gale Crater.

Since my April 27, 2018 update, Curiosity has continued its downward trek off of Vera Rubin Ridge back in the direction from which it came. The annotated traverse map to the right, cropped and taken from the rover’s most recent full traverse map, shows the rover’s recent circuitous route with the yellow dotted line. The red dotted line shows the originally planned route off of Vera Rubin Ridge, which they have presently bypassed.

It appears they have had several reasons for returning to the Murray Formation below the Hematite Unit on Vera Rubin Ridge. First, it appears they wanted to get more data about the geological layers just below the Hematite Unit, including the layer immediately below, dubbed the Blunts Point member.

While this is certainly their main goal, I also suspect that they wanted to find a good and relatively easy drilling candidate to test their new drill technique. The last two times they tested this new technique, which bypasses the drill’s stuck feed mechanism by having the robot arm itself push the drill bit against the rock, the drilling did not succeed. It appeared the force applied by the robot arm to push the drill into the rock was not sufficient. The rock was too hard.

In these first attempts, however, they only used the drill’s rotation to drill, thus reducing the stress on the robot arm. The rotation however was insufficient. Thus, they decided with the next drill attempt to add the drill’s “percussion” capability, where it would not only rotate but also repeatedly pound up and down, the way a standard hammer drill works on Earth.

I suspect that they are proceeding carefully with this because this new technique places stress the operation of the robot arm, something they absolutely do not want to lose. By leaving Vera Rubin Ridge they return to the more delicate and softer materials already explored in the Murray Formation. This is very clear in the photo below, cropped from the original to post here, showing the boulder they have chosen to drill into, dubbed “Duluth,” with the successful drill hole to the right.
» Read more

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Drilling success for Curiosity

11:16 am

For the first time in more than a year, Curiosity has successfully used its drill to obtain a sample from beneath the surface of Mars.

Curiosity tested percussive drilling this past weekend, penetrating about 2 inches (50 millimeters) into a target called “Duluth.”

NASA’s Jet Propulsion Laboratory in Pasadena, California, has been testing this drilling technique since a mechanical problem took Curiosity’s drill offline in December of 2016. This technique, called Feed Extended Drilling, keeps the drill’s bit extended out past two stabilizer posts that were originally used to steady the drill against Martian rocks. It lets Curiosity drill using the force of its robotic arm, a little more like the way a human would drill into a wall at home.

I plan to post a rover update either today or tomorrow, with more details about this success. Stay tuned!

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A close look at SpaceX’s new domination in the commercial launch industry

9:38 am

Link here. This is a surprisingly accurate and detailed article outlining the present state of the worldwide launch industry and how SpaceX has come to dominate it. It includes a graph that illustrates what I noted in my own summary in January: SpaceX has served to rejuvenate the American rocket industry.

From the Pentagon to financial analysts, many are heralding SpaceX as responsible for bringing the rocket industry back to the United States. For decades, rockets built by United Launch Alliance flew U.S. Air Force and NASA missions on Russian engines or other systems bought overseas. “They’re an all U.S. launcher. For a long time our military and intelligence capability was not launched using all U.S. capability,” Carissa Christensen, CEO of consulting firm Bryce Space and Technology, told CNBC.

The Air Force continues to award SpaceX hundreds of millions of dollars in launch contracts, with Secretary Heather Wilson telling Congress in March that the decreasing cost to launch is “enabling business plans to close in space that never were possible before.”

“For a decade and a half, launch costs were ballooning until SpaceX came in and said, ‘We can do it cheaper,'” Sam Korus, ARK Invest analyst, told CNBC.

SpaceX senior vice president Tim Hughes told Congress in a July testimony that “the U.S. had effectively ceded” the commercial rocket launch market “to France and to Russia.” Hughes showed how, before 2013, the U.S. lacked a foothold in this market. SpaceX helped the United States reclaim not just a portion but a majority in the global launch market in 2017 and represented more than 60 percent of U.S. launches while doing so.

The lower costs introduced by SpaceX has not merely allowed the U.S. to retake market share from the Russians and Europeans. It is also causing a re-awakening of the entire space industry. Satellites are being built and launched now that could not have been financed in the past, solely because the cost to put them in orbit has dropped. As a result the total number of launches is rising, providing more business for everyone.

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Why jets formed on Comet 67P/C-G

9:02 am

Scientists analyzing the data produced by Rosetta while it was flying in formation with Comet 67P/C-G have determined that the comet’s complex topology acted almost like nozzles to encourage evaporating material to form jets.

The new study shows for the first time that mainly the unusual shape and jagged topography of the comet are responsible for this phenomenon. The researchers analyzed images at different observation geometries of the Hapi region located on the “neck” of the comet, the narrow part connecting its two lobes. In computer simulations, they were able to reproduce these images thus gaining a better understanding of the driving processes.

In particular, two effects proved to be decisive. Some regions on the surface are located at lower altitudes or in the shade. The first rays of sunlight reach them later. In contrast, the frost evaporates particularly efficiently from the early and strongly illuminated regions. In addition, pits and other concave structures virtually concentrate gas and dust emissions – much like an optical lens.

This means that predicting the evaporation patterns on other comets will require first obtaining a detailed map of the surface, showing both its topography and make-up. This also means that any future explorers will first have to send a robot scouting mission so that they can plan a safe arrival during active periods.

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SpaceX successfully launches seven satellites, including two NASA science satellites

2:15 pm

Capitalism in space: SpaceX today successfully launched seven satellites, including two NASA science satellites and five Iridium communications satellites.

They did not attempt to recover the first stage, and though they tried to recover the rocket’s fairing it missed the ship and landed in the Pacific.

Intriguingly, all of these satellites were originally going to launch on a Russian/Ukrainian rocket.

Tuesday’s launch came about as a result of Russia’s Dnepr rocket becoming unavailable, in part due to the ongoing political situation in Ukraine. Grace Follow-On had been booked to fly aboard Dnepr, while Iridium had contracted for launches of the Russian vehicle to carry pairs of its spacecraft into orbit for testing, and later replenishment of its constellation. Early last year, Iridium and the GFZ – who are responsible for arranging GRACE’s ride to orbit – agreed to share a launch on SpaceX’s more powerful Falcon 9 rocket, splitting the costs while allowing the GRACE mission to continue and Iridium to get further satellites into orbit.

In other words, SpaceX has taken this business directly away from Russia.

The leaders in the 2018 launch standings:

15 China
10 SpaceX
5 Russia
5 ULA

In the national rankings, the U.S. is now in the lead with 16 total launches (including Orbital ATK’s Antares launch on Monday).

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New tests prove EM drive doesn’t work

11:26 am

Two different alternative concepts that proposed methods for creating thrust in space but defied known physics have both been found wanting in new stringent experiments.

The EM drive especially came off badly. Apparently the tiny residual force that remains after building the experiment rigorously and with care is caused not by the EM drive but by the Earth’s magnetic field.

Readers of Behind the Black know that I am a strong skeptic when it comes to flashy new discoveries, whether they are made by famous and well known cosmologists or some guys in their garage. To me, what matters is the data, and its reliability and robustness. The EM drive never passed the smell test. Good science experimentation has now proven this.

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ArianeGroup chief admits they can’t compete

9:36 am

In a newspaper interview the chief of ArianeGroup, the private joint partnership of Europe’s main rocket contractors Airbus and Safran, can’t seem to understand why competition and lowering prices is a good thing.

Rather than give you one or two quotes, it is better that you click on the link and read the whole. thing. Essentially, the heart of the problem is that ArianeGroup is building their new Ariane 6 rocket as an expendable, not reuseable, and thus they it will not be able to compete in the launch market expected in the 2020s. They made this decision based on the political needs of the European Space Agency rather then financial needs of the launch market. As such, the launch market is abandoning them.

What is amazing is this CEO’s complete lack of understanding of these basic economic facts. It suggests some very deep rot in both ArianeGroup and much of Europe’s commercial aerospace sector. If the person in charge does not understand market forces, who else at the company will?

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Two giant U.S. telescope projects team up

9:21 am

The two consortiums building the Thirty Meter Telescope (TMT) and the Giant Magellan Telescope (GMT) have teamed up in order to coordinate their research as well as encourage increased government funding for both.

The partnership, approved by the GMT board this month and by the TMT board last month, commits the two projects to developing a joint plan that would allow astronomers from any institution to use the telescopes; under previous plans observing time was available only to researchers from nations or institutions that had provided funding. The projects are discussing awarding at least 25% of each telescope’s time to nonpartners through a competitive process to be administered by the National Center for Optical-Infrared Astronomy—an umbrella organization that will replace the National Optical Astronomy Observatory (NOAO), based in Tucson, Arizona, sometime in fiscal year 2019. Telescope backers hope the public access plan will help persuade the federal government to pay for at least 25% of the total cost of the two facilities, which could total $1 billion. (Cost estimates for the GMT and the TMT are $1 billion and $1.4 billion, respectively, but astronomers expect both numbers to grow.) “There are many science projects that are $1 billion class projects,” says David Silva, NOAO’s director. “The investment that we would want is of a similar size.”

…In making their case, the teams will argue the benefits of having telescopes in both the northern and southern hemispheres. “When you are covering the whole sky, you have greater scientific reach,” says Wendy Freedman, an astronomer at The University of Chicago in Illinois who was the founding leader of the GMT. The teams will also argue that the telescopes have complementary strengths. The design of the GMT, for instance, makes it ideal for a high-resolution spectrograph designed to probe the atmospheres of exoplanets. The TMT, which has more light-gathering power, could host a multiobject spectrograph to quickly gather demographic statistics on the universe’s first galaxies. [emphasis mine]

The highlighted sentences explain everything. First, government funding for both projects has been weak, partly because the National Science Foundation (the funding agency) has not been able to make up it mind which of these two U.S. projects to back. By teaming up as one project building two telescopes, the builders hope they will grease the wheels of the federal funding machine.

Second, by selling these two telescopes as covering both the north and south hemispheres, they indicate that the TMT is now almost certainly going to abandon its Hawaii location and move to the Canary Islands. GMT will be built at the Las Campanas Observatory in Chile, located at 29 degrees south latitude. By placing TMT in the northern hemisphere at 29 degrees north latitude in the Canary Islands, rather than Mauna Kea’s 19 degrees north latitude, they better compliment GMT in the southern hemisphere.

In other words, this partnership strengthens the case for TMT to abandon Hawaii. Not only will construction begin sooner (as the Hawaiian government has shown no interest in approving the project), the higher latitude as part of this partnership better justifies funding.

And the odds of getting that funding have apparently increased, as the chair of the House appropriations panel that funds the National Science Foundation has just shown himself to be very willing to give telescope projects a lot of money, more in fact than they even request.

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ARCA’s CEO arrested by Homeland Security

8:56 am

We’re here to help you! Despite having all charges against him dropped, Homeland Security has arrested the CEO of the smallsat rocket company ARCA.

It’s not over yet. [Dumitru Popescu] was taken into custody by the Department of Homeland Security this morning, without warning.

When Dumitru was arrested in October of last year, The DHS cancelled his business visa, and provided him with a temporary visa, allowing him to stay until his case ended. Despite all charges against Dumitru being dismissed and Dumitru’s immediate efforts to restore his legal status in the US, he was taken into custody before he had a chance to do so.

This is absurd. The guy is very clearly not trying to get into the U.S. illegally. His company has actually won grants from NASA as well as other private companies. When the charges were dropped his business visa should have be reinstated instantly.

The result I think will be to kill his company, and its attempt to launch and test the first aerospike engine. This is a loss for both them and the United States.

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India clears GSAT-11 for launch

8:51 am

After pulling GSAT-11 back to India just prior to launch to make sure all was well, ISRO has now approved its launch.

Isro chairman K Sivan said, “All the tests on Gsat-11 at Bengaluru’s ISRO Satellite Centre (ISAC) are over. We have found no anomaly. We are in the process of discussion with Arianespace to fix the next launch date for our satellite.” Earlier, the Isro chief had told TOI that all tests would be completed by May 17.

Isro had postponed the launch of Gsat-11 initially planned on May 25 from the European spaceport as it did not want to take chances with its heaviest satellite especially after the signal failure episode with Gsat-6A. Communication satellite Gsat-6A, which was successfully launched from Sriharikota on March 29, went out of control during the third orbit-raising manoeuvre in space when the signal with the satellite got abruptly snapped because of suspected power failure. The space agency since then has been trying to restore the communication link with Gsat-6A though it knows its exact location through the satellite-tracking system.

Sivan is trained first as an engineer, so he took an engineer’s approach here, not a manager’s. Very wise. This bodes well for India’s space agency as long as he is in charge.

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China launches communications relay satellite for upcoming lunar mission

8:41 am

China successfully launched a satellite in the early hours this morning designed to relay communications between the Earth and an upcoming lunar lander aimed for the Moon’s far side.

The landing site for this mission is expected to be the Von Kármán crater in the South Pole-Aitken Basin. If successful, this will be the first spacecraft to land on the far side of the Moon.

As such, a communication relay will be required to communicate with Earth. Queqiao [the communication satellite’s name] will provide that role. Launched to an eventual L2 Halo Orbit (Earth-Moon L2 Lagrange Point), the satellite will have a lifetime of five years, covering both this and potentially another Chang’e mission.

The spacecraft is based on the CAST100 small satellite platform, with commonality to the often used DFHSat system that finds its way on to a number of Chinese spacecraft. It has a mass of 425kg and uses a hydrazine propulsion system. It will transmit telemetry back to Earth via its S-band antenna, while X-band data will provide the communication path between the lander and rover.

This Chinese lander could also be the first to confirm the existence of water ice on the lunar surface.

With this launch China once again ties the U.S. in launches for 2018. The leaders:

15 China
9 SpaceX
5 Russia
5 ULA

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Contamination found in shuttle engines to be used by SLS

12:03 am

Now we know why the first launch is likely delayed: It appears that contamination has been found in the used and refurbished shuttle engines that the Space Launch System is using.

A “routine quality assurance inspection” of the core stage, he said, discovered contamination in tubing in the engine section of the core stage, which hosts the vehicle’s four RS-25 main engines and associated systems. That contamination turned out to be paraffin wax, which is used to keep the tubes from crimping while being manufactured but is supposed to be cleaned out before shipment.

“The prime contractor determined the vendor was not fully cleaning the tubes and it was leaving residue in the tubes,” McErlean said. “This was retained as a requirement in the prime contractor’s spec, but it was not properly carried out.” Boeing is the prime contractor for the SLS core stage, but he did not disclose the vendor who provided the contaminated tubing.

The contamination was initially found in a single tube, he said, but later checks found similar residue in other tubes. All the tubing in the core stage is now being inspected and cleaned, a process he said is not straightforward because of the “mass of tubing” in the engine section and also because cleaning is a “non-trivial process.”

Some obvious questions immediately arise:

1. These engines were previously flown on the space shuttles, numerous times. How did the paraffin wax, used “to keep the tubes from crimping while being manufactured,” remain in the tubes during all those shuttle flights?

2. Assuming the tubes were a new addition or replacement during the refurbishing process, it still seems astonishing that a subcontractor could be so lax. Did they really believe the wax did not need to be thoroughly cleaned?

3. While they have admitted that they will likely have to delay the launch because of issues with the core stage, why do they deny this contamination problem is the cause? More important, how much is it costing to fix? And how much time are they actually losing to fix it?

4. Finally, this is only one of many similar problems that we have seen with this entire project. Boeing and NASA have gotten so far about $40 billion to build this rocket, and have been working on it since 2006, more than a dozen years ago. Furthermore, they supposedly are building it using shuttle equipment in a Saturn rocket-type design in order to save money and time. Instead, they have wasted billions and taken more than three times longer than it took us to win World War II to get to a point where the program still has not flown.

Does anyone really believe this project is anything but a huge boondoggle? And if so, can they please tell me how it will be possible for the United States to really explore the heavens with a project run this incompetently?

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Block 5 Falcon 9 first stage returns to port

9:35 am

SpaceX’s first Block 5 first stage for its Falcon 9 rocket, designed to fly a minimum of ten times, has returned to port after its first flight last week.

This is the most interesting detail revealed:

While not visible, the most significant improvements are likely to be found at the base of the first stage’s octaweb – now assembled with bolts instead of welds – in the form of a dramatically improved heat shield around its nine Merlin 1D engines (also upgraded, of course). One of the Falcon recovery technicians showed some exceptional interest in the shield and Merlins, likely documenting their condition in extreme detail to inform engineering reviews of the pathfinder rocket after its first flight test.

The pictures show those bolts quite clearly.

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Mars cubesats take picture of Earth and Moon

12:36 am

One of the two MarCO cubesats heading to Mars on the first interplanetary cubesat mission, has taken its a picture of the Earth and the Moon.

NASA set a new distance record for CubeSats on May 8 when a pair of CubeSats called Mars Cube One (MarCO) reached 621,371 miles (1 million kilometers) from Earth. One of the CubeSats, called MarCO-B (and affectionately known as “Wall-E” to the MarCO team) used a fisheye camera to snap its first photo on May 9. That photo is part of the process used by the engineering team to confirm the spacecraft’s high-gain antenna has properly unfolded.

As a bonus, it captured Earth and its moon as tiny specks floating in space.

In a few weeks the two cubesats will make a mid-course correction, also the first time a cubesat has attempted such a thing.

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Another delay for SLS

8:36 am

This really isn’t news: Work on the core stage for the first SLS rocket launch appears to face another three month delay, threatening the scheduled June 2020 launch date.

The article outlines in great detail the work being done on the SLS core stage, and where the delays might be coming from, while also being vague about what exactly is causing the delay.

It is unknown if the additional time for completion of final assembly of the whole rocket stage is based on the engine section, the other four elements, or continuing refinement of forward work. Most of the hardware and systems that will fly on EM-1 are being built for the first time and the procedures to connect the five pieces of the Core Stage together will also be attempted for the first time.

Of the five elements, the most recent news had the Forward Skirt near completion of its individual work by the end of the month. Work to cover the liquid oxygen tank with its Thermal Protection System (TPS) foam was in final phases, with the liquid hydrogen tank to follow behind it. The engine section and intertank elements continue to be outfitted with propellant lines, pressure tanks, avionics boxes, wiring, and other equipment.

Once complete, the elements will be assembled vertically in two stacks before a horizontal join of the halves of the rocket kicks off final assembly.

In fact, reading the article’s detailed description of the testing and assembly of SLS’s core stage struck me as incredibly slow-paced, so slow paced that it actually filled me with a sense of ennui. In the time they seem to need to only do an equipment review, SpaceX appears to have upgraded and flown a new version of its Falcon 9 first stage, while also redesigning a new core stage for its Falcon Heavy.

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Europa water plume detected in old Galileo data

8:22 am

Using old Galileo data and new techniques of analysis scientists have uncovered a water plume on Europa that the spacecraft flew through in 1997.

Over the course of 5 minutes, spikes the spacecraft recorded with its magnetic and plasma sensors reflected the alterations that a veil of ejected water, from one or many vents, could cause in a region matching the telescope observations, they report today in Nature Astronomy. This indicates that a region of the moon potentially 1000 kilometers long could host such activity, though it is impossible to say whether this is a single plume or many, like the complex system of fractures and vents seen on Enceladus. Indeed, on its own, this evidence was too weak to tie to erupting water in a 2001 study describing it, the authors add, but it fits well with the Hubble and modeled evidence.

As indicated by the quote above, the result has a lot of uncertainty.

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Chaos on Mars

11:56 am

chaos terrain

Cool image time! The image on the right, cropped and reduced in resolution to post here, shows an area on Mars that geologists have dubbed “Chaos Terrain.” If you click on the image you can see the full image, which also includes several canyons oriented in what seem to be random directions.

I first heard this geological term for regions on Mars shortly after the first orbital missions circling Mars began taking images back in the 1970s. It applied to places where the terrain was hummocky, a crazy collection of hills forming no pattern at all. Earth does not really have such terrain.

The close-up to the right also shows that at least one of these hills is fractured, made up of several large pieces that have separated over time.

This image was part of the May 2nd image release from the high resolution camera on Mars Reconnaissance Orbiter. What makes it interesting is its location on Mars. The image below shows that location, indicated by a white cross.
» Read more

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ULA picks Aerojet Rocketdyne engine for Vulcan upper stage

9:35 am

Capitalism in space: ULA has chosen an Aerojet Rocketdyne engine to power the upper stage of its next generation rocket Vulcan.

The company has not yet made a decision on the engine for the first stage, where Blue Origin’s BE-4 still appears favored over Aerojet Rocketdyne’s AR-1 engine. This decision on the upper stage could partly be a political move, giving Aerojet the upper stage in order to make it easier to give the lower stage to Blue Origin.

ULA is forced to play politics here because politicians are involved. A number of power members of Congress want Aerojet Rocketdyne to get the business, and ULA risks offending these legislators should it abandon that company entirely.

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Hiding messages using fonts

9:26 am

A new computer technique has been developed that uses subtle changes to a document’s fonts to encode secret messages and data.

Using Columbia University’s FontCode system, however, users can hide messages within unrelated text via virtually-invisible changes to the displayed letters.

Developed by a team led by associate professor of computer science Changxi Zheng, FontCode works with commonly-used fonts such as Times Roman, Helvetica, and Calibri, plus it’s compatible with most word processing programs. Additionally, the hidden messages are retained even when the document is printed on paper or converted to a different file type.

The video at the link explains very nicely how this works. The technology has some excellent potentially positive applications, such as providing a method of finding out if an original document has been modified. It also carries with it a great potential for misuse because of its ability to hide information unobtrusively in a written document.

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