Tag: spaceflight

Juno’s look at Jupiter’s Great Red Spot

3:10 pm

The Juno science team released its results from the spacecraft’s first close fly over of Jupiter’s Great Red Spot in July 2017.

Jupiter’s Great Red Spot is a giant oval of crimson-colored clouds in Jupiter’s southern hemisphere that race counterclockwise around the oval’s perimeter with wind speeds greater than any storm on Earth. Measuring 10,000 miles (16,000 kilometers) in width as of April 3, 2017, the Great Red Spot is 1.3 times as wide as Earth.

“Juno found that the Great Red Spot’s roots go 50 to 100 times deeper than Earth’s oceans and are warmer at the base than they are at the top,” said Andy Ingersoll, professor of planetary science at Caltech and a Juno co-investigator. “Winds are associated with differences in temperature, and the warmth of the spot’s base explains the ferocious winds we see at the top of the atmosphere.”

The future of the Great Red Spot is still very much up for debate. While the storm has been monitored since 1830, it has possibly existed for more than 350 years. In the 19th century, the Great Red Spot was well over two Earths wide. But in modern times, the Great Red Spot appears to be diminishing in size, as measured by Earth-based telescopes and spacecraft. At the time NASA’s Voyagers 1 and 2 sped by Jupiter on their way to Saturn and beyond, in 1979, the Great Red Spot was twice Earth’s diameter. Today, measurements by Earth-based telescopes indicate the oval that Juno flew over has diminished in width by one-third and height by one-eighth since Voyager times.

The storm’s estimate depth, about 200 miles, seems gigantic, but then we must remember this storm is on a gas giant that is about 88k miles in diameter, about ten times larger than Earth. The relative size of this storm to the size of Jupiter therefore is really not that much different than the relative size of big hurricanes on Earth. At the same time, the realities here are daunting, filled with unknowns, chief of which is the fact that unlike Earth, the Great Red Spot is a storm that is floating high in the atmosphere with no solid surface below it.

One comment

Trump signs new space policy directive, making Moon 1st priority again

2:57 pm

Yawn. President Trump today signed a new space policy directive that makes the Moon the U.S.’s first exploration priority again.

“The directive I am signing today will refocus America’s space program on human exploration and discovery,” said President Trump. “It marks a first step in returning American astronauts to the Moon for the first time since 1972, for long-term exploration and use. This time, we will not only plant our flag and leave our footprints — we will establish a foundation for an eventual mission to Mars, and perhaps someday, to many worlds beyond.”

As I wrote above, yawn. Same old same old. In 2004 Bush declared we will go to the Moon. In 2010 Obama declared we will go to an asteroid. In 2017 Trump declares we will go to the Moon.

In all those years, where have we actually gone? Nowhere. The government’s effort during all that time to build a rocket and a manned spacecraft to do any of this stuff has come up completely empty. Neither will carry humans into space for at least another five years, if not longer.

The only thing these empty promises have accomplished is to waste a god-awful amount of taxpayer money, now about $33 billion, with appropriations likely to increase that to more that $43 billion before that first manned SLS/Orion flight.

I predict that this government promise will come up empty as well, at least in the manner the government and NASA is trying to sell it. It won’t be the government rocket and capsule that will get us back to the Moon, but a host of new private companies, making profits and doing things efficiently and fast, that will get us there. And I am firmly confident that they will do it before the government even gets off the ground.

14 comments

New method to 3D print entire objects simultaneously, without layering

10:56 am

Life imitates science fiction: Engineers at Lawrence Livermore Lab have developed a new 3D method that creates entire objects in one piece instead of building them up with layering.

Developed by LLNL in collaboration with UC Berkeley, the University of Rochester, and MIT, volumetric printing replaces layering with a process that creates the entire object simultaneously. It does this by using three overlapping lasers beamed in a hologram-like pattern into a transparent tank filled with photosetting plastic resin. A short exposure by a single beam isn’t enough to cure the resin in a short time, but combining three lasers can induce curing in about ten seconds. After the object is formed, the excess resin is then drained off to reveal the complete unit.

“The fact that you can do fully 3D parts all in one step really does overcome an important problem in additive manufacturing,” says LLNL researcher Maxim Shusteff. “We’re trying to print a 3D shape all at the same time. The real aim of this paper was to ask, ‘Can we make arbitrary 3D shapes all at once, instead of putting the parts together gradually layer by layer?’ It turns out we can.”

Volumetric printing is not only faster, but eliminates the need for temporary support structures, is more flexible, and provides more geometric flexibility. So far, it’s been used to create squares, beams, planes, struts at arbitrary angles, lattices, and complex, curved objects.

The process still has problems, as the article describes. Nonetheless, this is just one more step in the invention process that is making a Star Trek replicator possible.

Hat tip reader Mike Buford.

6 comments

Breakthrough Listen to observe Ourmuamua

10:47 am

Breakthrough Listen, one of billionaire Yuri Milner’s Breakthrough initiatives, is going to do an observation campaign of the interstellar object Ourmuamua using the Green Bank Radio telescope.

It has a highly unusual structure for an asteroid – an elongated cigar shape, hundreds of meters in length but with width and height perhaps only one tenth as long.

Researchers working on long-distance space transportation have previously suggested that a cigar or needle shape is the most likely architecture for an interstellar spacecraft, since this would minimize friction and damage from interstellar gas and dust. While a natural origin is more likely, there is currently no consensus on what that origin might have been, and Breakthrough Listen is well positioned to explore the possibility that ‘Oumuamua could be an artifact.

Listen’s observation campaign will begin on Wednesday, December 13 at 3:00 pm ET. Using the Robert C. Byrd Green Bank Telescope, it will continue to observe ‘Oumuamua across four radio bands, from 1 to 12 GHz. Its first phase of observations will last a total of 10 hours, divided into four “epochs” based on the object’s period of rotation.

If anything, this observation will provide us more information about Ourmuamua itself, which unfortunately is very limited because the object was already on its way out when it was discovered.

3 comments

Lawsuit reveals two customers for Soyuz circumlunar tourist flight

8:50 am

Capitalism in space: A lawsuit against Space Adventures, the company that has previously organized tourist trips to ISS using Russian rockets, has finally revealed the names of the two individuals who had purchased tickets for a circumlunar flight around the Moon using a modified Soyuz capsule.

The details are included in a lawsuit now winding its way through U.S. District Court in Virginia. Harald McPike, a wealth Austrian investor and adventurer who resides in the Bahamas, has sued Space Adventures, its chairman and CEO Eric Anderson, and its president Thomas Shelley seeking to recover the $7 million down payment he put down on the flight in March 2013.

The other lunar tourist? The lawsuit says Space Adventures told McPike that it was Anousheh Ansari, who flew to the International Space Station (ISS) as a tourist in 2006 on a Soyuz in a deal the company brokered with the Russians. Ansari’s family also sponsored the $10 million Ansari X Prize won by Burt Rutan’s SpaceShipOne in 2004.

The dispute centers on McPike’s realization, after paying $7 million of the $30 million down payment, that Space Adventures probably could not deliver on its promises, mostly because of a Russian reluctance to sent tourists on such a mission. He wants his money back, and Space Adventures doesn’t want to return it.

While several modified Soyuz capsules, called Zond, were sent around the Moon during the 1960s, that was a very long time ago. Configuring the modern Soyuz for such a manned mission would require a lot of work, and I suspect the Russians didn’t want to do it without money up front. Moreover, I’m not even sure that the $300 million from the two tourists would have been sufficient.

4 comments

Update on Russia’s troubled Sea Launch

8:35 am

Link here. It appears that the launch platform faces numerous additional obstacles before it can become operational again, including complex political maneuvering withing Russia and with Ukraine.

Yuzhmash officials [in Ukraine] gave their Russian counterparts at the S7 Group a list of components which are no longer available for the Zenit [rocket]. One of the most important items on the list is the ignition systems produced in the Lugansk region which has been taken over by pro-Russian rebels and remains practically cut off from the rest of Ukraine. The igniters burning black powder are used to initiate small solid-propellant motors which generate reverse thrust to facilitate the safe separation of the first and second stages during the ascent of the Zenit rocket to orbit.

According to industry sources, the S7 company has been so far unable to secure the delivery of Russian equivalents of the necessary hardware and materials, probably due to lack of permissions from Moscow. Instead, the S7 Group asked KB Yuzhnoe to organize the production of missing components in Ukraine. However, in the case of black powder, launching its production in Ukraine would not make economic sense due to lack of other applications beyond the very small amount required for the ignition systems, one source said.

Some observers question whether the S7 company has a real motivation to see the Sea Launch venture through because the airline with no prior experience in the space launch business ended up with the Sea Launch assets in its lap likely under pressure from the Kremlin. [emphasis mine]

S7 has also proposed using the Sea Launch platform to launch Russia’s next generation unmanned freighter, but this faces numerous technical issues. Regardless, the highlighted sentence above indicates how much the Russian government and the top-down Russian approach to everything interferes with efficient operations. It suggests that S7 didn’t buy into Sea Launch because it thought it could make money on it, but because of political pressure. Such pressure does not produce effective and profitable companies.

One comment

Blue Origin to resume New Shepard test flights next week?

3:41 pm

Capitalism in space: An FAA airspace notice published yesterday strongly suggests that Blue Origin will resume test flights of its New Shepard suborbital spacecraft next week.

The Notice to Airman, or NOTAM, published by the FAA on its website Dec. 9 closes airspace above Blue Origin’s test site between Dec. 11 and 14, from 9:30 a.m. to 4 p.m. Eastern each day. The closure is to “provide a safe environment for rocket launch and recovery.” The NOTAM does not give additional details about the planned activities, but does identify Blue Origin as the point of contact regarding the airspace closure.

The flight will test a new capsule and propulsion unit, as the vehicle that was test flown multiple times in the previous test flights has been retired. What is interesting is that the company says it is building more than one. This will give them a fleet which will allow them a rapid launch rate.

One comment

New Horizons successfully does course correction

8:54 am

New Horizons yesterday successfully fired its engines for 2.5 minutes to refine its course and January 1, 2019 fly-by of Kuiper belt object 2014 MU69.

The maneuver both refined the course toward and optimized the flyby arrival time at MU69, by setting closest approach to 12:33 a.m. EST (5:33 UTC) on Jan. 1, 2019. The prime flyby distance is set at 2,175 miles (3,500 kilometers); the timing provides better visibility for DSN’s powerful antennas to reflect radar waves off the surface of MU69 for New Horizons to receive – a difficult experiment that, if it succeeds, will help scientists determine the reflectivity and roughness of MU69’s surface.

The spacecraft will next be put in hibernation on December 21, and stay in that state until June.

One comment

ARCA’s CEO provides update on charges against him

8:34 am

Capitalism in space: The CEO of ARCA, Dumitru Popescu, yesterday released a youtube video where he provides an update on the fraud and embezzlement charges against him.

He spends most of the video describing what happened when he was arrested. However, he also says that he and his attorney have now seen the evidence against him, and though he cannot discuss it yet he is confident that he will be found innocent in court.

The man appears sincere, but who knows. We shall see. He also says that ARCA is moving forward, though he also admits that his arrest was a setback for the company.

One comment

Another Juno fly-by movie of Jupiter!

9:09 am

Cool movie time! Using 125 Juno images taken when it flew past Jupiter on its third orbit in December 2016, citizen scientist Gerald Eichstädt has produced a beautiful short movie showing that flyby. I have embedded it below.

At the link he provides very specific details on how he created this move. I found this detail however most fascinating:

Most repetitive bright and dark camera artifacts are patched. Due to the intense radiation near Jupiter, several additional bright pixels occured. Those aren’t patched in this animation.

In rarer cases, lightnings on Jupiter might also show up as bright pixels. [emphasis mine]

8 comments

Major fund-raising effort for Japanese lunar mining company

8:58 am

Capitalism in space: The Japanese company behind Japan’s Google Lunar X-Prize finalist, ispace, announced this week a major effort in the coming weeks to obtain investment capital for its proposed lunar mining projects planned for the next decade.

ispace’s website indicates the next phase beyond the prize competition involves prospecting the moon between 2018 and 2023. Missions will include “mapping valuable resources…to determine economic value of resources. Our rover swarms are deployed on the Moon to scout crater and cave locations on the lunar poles that have a high probability of resource discovery,” the company says. In the third phase from 2024 to 2030, the company plans to “work with our strategic partners to collect, store, and deliver these valuable resources to our government, institutional, scientific, and private space customers.”

Whether its team can win the X-Prize however remains unclear, since it is dependent on the same PSLV launch that the Indian X-Prize team is buying, and that team still needs to raise $35 million to pay for the launch.

2 comments

Rocket Lab delays test launch until Friday

11:25 pm

Capitalism in space: Rocket Lab’s second test launch of its Electron rocket has been delayed until Friday (U.S. time) to give the company more prep time.

Liftoff with three commercial CubeSat payloads was planned as soon as Thursday night, U.S. time, but officials said they needed more time.

The company transported the Electron vehicle to its launch base last month, after completing full-up hotfire testing. The launch team rehearsed countdown procedures last week, and practiced loading kerosene and liquid oxygen propellants into the rocket. “We did a hotfire campaign as a big preparatory test, so all that was done over a month ago,” said Shaun O’Donnell, Rocket Lab’s vice president of global operations. “The wet dress rehearsal went really well. It went really smooth, especially for our first run at it, so we’re really confident.”

6 comments

Former Google Lunar X-Prize competitor still alive

8:26 am

Capitalism in space: Part Time Scientists, a Germany company partly sponsored by Audi that was formerly a competitor for the Google Lunar X-Prize, has reiterated its plans to land a privately-built and funded rover near the Apollo 17 landing site, and to do it careful so as to not damage the site’s historical significance.

The company has pledged its support to the organization For All Moonkind, which is dedicated to protecting the Apollo landing sites.

A review of the PTScientists website however provides little information on the company’s test schedule leading up to this lunar rover mission. I must therefore remain skeptical.

Leave a comment

UAE invites its citizens to apply to join its astronaut program

9:51 am

The new colonial movement: The United Arab Emirates (UAE) today launched its astronaut program, inviting its citizens to apply for four positions that they hope to eventually fly to ISS.

Much of this effort is simply propaganda designed to push the UAE to diversify its economy and encourage aerospace development. Nonetheless, when SpaceX’s Dragon and Boeing’s Starliner are operational there will be nothing to prevent those companies from selling seats on them to the UAE, much as the Russians have done with tourists in the past. In fact, I expect this to happen.

Leave a comment

Wall St pushes to have SpaceX save Tesla

9:36 am

Three articles in the news today illustrate both the corruption of the press as well as a desire of one analyst on Wall Street to convince Elon Musk to use his success at SpaceX to save Tesla.

All three news articles are based on a single recommendation made by one Morgan Stanley research analyst. Thus, the headline in the first article is an outright lie. There isn’t growing speculation, there is one guy with an opinion, an opinion by the way that Elon Musk doesn’t appear to share, according to the third article.

Musk said last year that there was too little cooperation between Tesla and Space Exploration Technologies Corp. to justify merging the two, dismissing the idea that had been raised by one of Jonas’s colleagues as “quite tenuous.”

From SpaceX’s point of view, combining these companies makes little sense. It would essentially be using the success of SpaceX to prop up Tesla’s financial weakness.

Musk of course controls both companies, and can do this if he wishes. If I was Musk, however, I would keep the companies separate, and let the chips fall where they may. Musk however might care enough about Tesla that he might want to save it, using SpaceX’s profits. If he does, however, he will instantly weaken SpaceX, as it will then no longer have as much cash available to pay for its future plans, such as the Big Falcon Rocket.

3 comments

Private commercial supersonic jet gains funding

11:36 am

A private commercial supersonic jet company, Boom Supersonic, has gained significant investment funding since it first revealed its design concept in March.

Boom, whose suppliers include General Electric Co, Boeing, Honeywell International Inc and Netherlands-based TenCate Advanced Composites, has reportedly received 76 pre-orders from airlines, excluding the option of up to 20 aircraft from Japan Airlines. As of March 2017, the firm had raised about $41 million (£30.5 million) in funding.

Yoshiharu Ueki, president of Japan Airlines, added: ‘Through this partnership, we hope to contribute to the future of supersonic travel with the intent of providing more “time” to our valued passengers while emphasising flight safety.’

The firm has previously revealed that initial test flights for its 1,451mph (2,330kph) aircraft, nicknamed ‘Baby Boom’, will begin by the end of 2018.

Including the JAL preorder that makes 96 airplane sales total. It appears that this company is increasingly for real.

One comment

Calculating the number of alien space artifacts in our solar system

10:53 am

Link here. The author attempts to make a back of the envelope calculation of the number of abandoned alien interstellar spacecraft in the Milky Way (like our Voyager and Pioneer spacecraft), and from this calculate the number that might actually be drifting through the solar system. His conclusions?

Wondering if there’s any alien goodies in our solar system?

Well, the distance inner edge of the Oort cloud is estimated to be 4,000 A.U. This would make the volume of the solar system = 201 million cubic A.U.s, and the chance of an alien artifact adrift in our solar system (other than our own) is less than 1 in a 1,000,000. Using the outer edge distance for the Oort cloud at 50,000 AU = gives the volume of the solar system at 31.4 billion, with a slightly better than 1-in-45 chance.

But the nearest star system, Alpha Centauri is 4.4 light years distant, which equals a sphere 243 cubic light years in volume, with lots of elbow room for alien space junk!

The author also admits that these calculations depend on many assumptions, and should not be taken very seriously. Nonetheless, they are intriguing, and fun to consider.

10 comments

Another negative op-ed of India’s oppressive draft space law

10:04 am

Link here. Unlike the first negative op-ed earlier this week, the writer of today’s op-ed gets closer to the heart of the problem.

It is proposed that all powers to licence private players to launch and operate “space objects” will rest with the Union government (read DoS). And these powers will be quite sweeping. DoS will not only have powers to “grant, transfer, vary, suspend or terminate licence” but also have powers to inspect books of accounts and other documents of licensees and seek all information about partners, directors, etc.

This is particularly worrying because “space activity” under this proposed law not only covers launch of satellites but also “use of space objects” as well as “operation, guidance and entry of space object into and from outer space and all functions for performing the said activities.” This would technically mean even data companies handling satellite imagery or universities operating ground facilities for their microsatellites may also need a licence. If this is going to be so, it is a recipe for a new “licence raj”.

The writer is of course correct. The law as written gives all power and control to India’s government and its bureaucracy, a sure recipe for discouraging private enterprise. However, this writer also avoids the law’s worst component, that it places ownership of all space objects — rockets, satellites, and what they produce — with the government, not the private sector. Such a rule will not only squelch any commercial space development in India, it will likely cause private companies outside of India from buying India’s launch services. Why would I place my satellite on an Indian rocket if that country’s law means I will then no longer own it?

Leave a comment

Vostochny failure points to serious problems in Russian aerospace

9:18 am

This update on the launch failure at Vostochny last week suggests there are some very serious problems permeating the entire Russian aerospace industry.

According to a post on the online forum of the Novosti Kosmonavtiki magazine, the Fregat stage for the ill-fated first mission from Vostochny was originally built for the launch of the Rezonans scientific satellites from Baikonur.

At the same time, experts agree that the problem could theoretically have been resolved before launch, if not for the poor coordination between the developers of the flight control systems of the Soyuz-2 launch vehicle and their colleagues working on flight controls for the Fregat. As one poster on the Novosti Kosmonavtiki forum noted: in the deluge of pre-launch paperwork between RKTs Progress in Samara, which built Soyuz-2, and NPO Lavochkin, which developed Fregat, discussing a multitude of legal issues, confirming and reconfirming various agreements and reminders, there was not a single memo attracting the developers’ attention to a different alignment of the launch pad in Vostochny from that of other sites. Obviously, such information was buried in the working documentation on the mission, but nobody thought about the effect of this fact on the launch. The lower echelon of engineers simply missed that detail, while top managers had no idea at all, because, the majority of them lacked the necessary qualifications, the poster said. [emphasis mine]

Top managers who “lack the necessary qualifications?” This smacks of a corrupt hiring system having nothing to do with qualifications or the need to do good work. It also is typical of a government-run operation, which the entire Russian aerospace industry is after Putin consolidated it all into one single cooperation under government control in 2014. And prior to that the big Russian companies didn’t really operate under a system of free competition, but like mob gangsters they divided up the work among themselves and then worked together to prevent any new competition from forming.

I’m not sure how Russia is going to fix this. In a free market the solution would be for competition to produce new companies with fresh ideas, forcing the bad companies out of business. Putin’s consolidation combined with a Russian culture that does not seem to understand the idea of competition appear to make that process difficult, if not impossible.

4 comments

Israeli competitor for X-prize faces shutdown due to lack of funds

9:06 am

Capitalism in space: SpaceIL, the Israeli finalist in the Google Lunar X-Prize competition, must raise $20 million in the next two weeks or face shutdown, even as they are about to complete testing on their rover.

This is the second of five finalists facing shutdown due to an inability to raise enough investment funds. With a third depending on a rocket that might not be operational by the March 31, 2018 deadline, the prize looks increasingly like no one will win it.

This does not mean that none of the companies will succeed, only that at least one or two might fly after the deadline. If they do, they will still demonstrate that they have the ability to launch a scientific planetary mission for pennies (compared to what the government has been spending). At that point I would expect them to become very viable and profitable spacecraft companies. Thus, it would actually be a good investment for some rich person to put their money behind these projects. In the case of SpaceIL, however, the problem might be that it is a non-profit. It appears it is not designed to be a profitable company down the road, but to merely serve propaganda purposes now.

Anchored in the “can-do”, innovative approach and creative energy that has characterized the Jewish State since its founding, SpaceIL aims to replicate the “Apollo Effect” in Israel, inspire and motivate the next generation of Israelis to pursue a future in STEM professions. Since its establishment as a nonprofit, SpaceIL has pledged to donate the $20 million in prize money, if it wins, to the promotion of science and scientific education in Israel, and to thus contribute to Israel’s economy and security.

Since its founding, many have contributed to the project. The main donor is the Dr. Miriam and Sheldon Adelson Foundation. Additional supporters include Morris Kahn, Sami Sagol, Lynn Schusterman and Steven Grand, among others. The project formed exceptional collaborations between the private sector, the academia and governmental companies. Israeli Aerospace Industries (IAI), the Weizmann Institute of Science, Tel-Aviv University, Israel Space Agency, Israeli Ministry of Science, Bezeq, dozens of engineers and hundreds of volunteers are among SpaceIL’s partners. Over the years, SpaceIL volunteers have reached half a million children and youths throughout the country.

All of this has wonderfully good intentions, but I think they would be better served to focus on making money. A successful and profitable space company will do far more to inspire Israel’s children than mere propaganda.

Leave a comment

China launches another military satellite

8:46 am

The race between Russia, China, and SpaceX for the most launches in 2017 tightened today with another successful Chinese launch this morning of a classified military satellite using its Long March 2D rocket.

The race as of today:

27 United States
18 Russia
16 SpaceX
14 China

According to this article as well as SpacflightNow’s launch log), China, Russia, and SpaceX all have three more launches scheduled in 2017. If that is what happens, these standings will not change.

Leave a comment

Tesla aimed for Mars will be the payload on first Falcon Heavy launch

8:51 am

Capitalism in space: Elon Musk announced today that the first test launch of a Falcon Heavy rocket next month will carry a Tesla car which will be aimed for a solar orbit about the same distance from the Sun as Mars.

Payload will be my midnight cherry Tesla Roadster playing Space Oddity. Destination is Mars orbit. Will be in deep space for a billion years or so if it doesn’t blow up on ascent.

Musk definitely knows how to generate publicity, even as he lowers expectations for the launch. Richard Branson could learn something from him.

13 comments

Soyuz launches military satellite, despite failure earlier this week

8:42 am

A Russian Soyuz rocket today successfully launched a military satellite, despite the launch failure from improper software earlier this week.

The reason they launched this Soyuz was because of two reasons. First, it was not using the Fregat upper stage that had had the incorrect programming. Second, it launched from Plesetsk, a Russian spaceport they have used since the beginning of the space age. The failure launched from the new spaceport at Vostochny, with software that had not been updated for that spaceport.

This launch widens the Russian lead in successful launches over SpaceX for 2018. The U.S. however still leads handily overall.

27 United States
18 Russian
16 SpaceX
13 China

Leave a comment

The fly-by anomaly returns with Juno

9:48 pm

The uncertainty of science: An orbital discrepancy between where engineers predict where Juno should be and where it actually is suggests it represents the recurrence of an anomaly that has been seen with numerous past planetary spacecraft.

During the 1970s when the Pioneer 10 and 11 probes were launched, visiting Jupiter and Saturn before heading off towards the edge of the Solar System, these probes both experienced something strange as they passed between 20 to 70 AU (Uranus to the Kuiper Belt) from the Sun.

Basically, the probes were both 386,000 km (240,000 mi) farther from where existing models predicted they would be. This came to be known as the “Pioneer anomaly“, which became common lore within the space physics community. While the Pioneer anomaly was resolved, the same phenomena has occurred many times since then with subsequent missions.

…Another mystery is that while in some cases the anomaly was clear, in others it was on the threshold of detectability or simply absent – as was the case with Juno‘s flyby of Earth in October of 2013. The absence of any convincing explanation has led to a number of explanations, ranging from the influence or dark matter and tidal effects to extensions of General Relativity and the existence of new physics.

However, none of these have produced a substantive explanation that could account for flyby anomalies.

The article describes in detail an effort to pin down the extent of Juno’s orbital anomaly, and to use that information to develop a model that would explain the phenomenon. Not surprisingly, they have not really come up with a comprehensive explanation. To me, the variability of the phenomenon suggests that it isn’t real, that it is either an unmeasured instrument effect or an ordinary component of solar system travel and orbital mechanics that programmers have not yet pinned down. For example, the gravitational effect of every planet and rock in the solar system will influence the path of a spacecraft, though with most that influence will be very small. It would not surprise me if this anomaly is simply the consequence of missing some of this influence.

13 comments

Voyager 1 fires thrusters not used in 37 years

3:30 pm

Because Voyager 1’s primary attitude thrusters are beginning to show wear (after forty years in space), engineers decided to experiment using a different set of thrusters not used since the spacecraft flew past Saturn in 1980, and found that they worked!

In the early days of the mission, Voyager 1 flew by Jupiter, Saturn, and important moons of each. To accurately fly by and point the spacecraft’s instruments at a smorgasbord of targets, engineers used “trajectory correction maneuver,” or TCM, thrusters that are identical in size and functionality to the attitude control thrusters, and are located on the back side of the spacecraft. But because Voyager 1’s last planetary encounter was Saturn, the Voyager team hadn’t needed to use the TCM thrusters since November 8, 1980. Back then, the TCM thrusters were used in a more continuous firing mode; they had never been used in the brief bursts necessary to orient the spacecraft.

…On Tuesday, Nov. 28, 2017, Voyager engineers fired up the four TCM thrusters for the first time in 37 years and tested their ability to orient the spacecraft using 10-millisecond pulses. The team waited eagerly as the test results traveled through space, taking 19 hours and 35 minutes to reach an antenna in Goldstone, California, that is part of NASA’s Deep Space Network.

Lo and behold, on Wednesday, Nov. 29, they learned the TCM thrusters worked perfectly — and just as well as the attitude control thrusters.

They figure these back-up thrusters will allow them to extend the mission by two or three years. The test also went so well that they now plan to do the same test on Voyager 2, which has still not entered interstellar space.

10 comments

Watch a rocket tank being built, mostly by robots

10:39 am

Capitalism in space: The video below the fold shows the process by which Interorbital Systems built a rocket test tank for the Neptune smallsat rocket it is developing. It is definitely worth watching if you want to see the future of complex manufacturing. Robotic equipment does most of the work, in a precise manner that would be impossible for humans, which therefore allows for the construction of engineering designs that were previously impossible or too expensive. Now, such designs can be built relatively cheaply, and repetitively.

Hat tip Doug Messier at Parabolic Arc.

» Read more

5 comments

Development at SpaceX’s Texas spaceport to pick up in 2018

10:31 am

Capitalism in space: Though construction at SpaceX’s Texas spaceport has been slower than expected, the company expects to accelerate development in 2018.

According to SpaceX, [people] won’t have to wait much longer for an increase in activity at the future spaceport. The recently installed antennas at Boca Chica are expected to be operational next year — although they’ll initially track flights blasting off from elsewhere — and the company also indicated development of the overall launch complex should pick up. “Even as our teams worked to modernize and repair our launch complexes in Florida so that we could reliably return to flight for our customers, SpaceX invested $14 million into the South Texas project,” said Gleeson, the company’s spokesman.

“Now, with our launch construction projects in Florida wrapping up by early 2018, SpaceX will be able to turn more attention to our work in South Texas,” he said.

In other words, once SpaceX has got its two launchpads in Florida both up and running, including the first use by the Falcon Heavy of one of those pads, the company will then be able to shift its launchpad operations down to Texas.

The article outlines in detail many of the reasons the development has been slow, but I think the issues highlighted in the quote above, issues I had not considered previously, might be the most important. After the September 2016 launchpad explosion in Florida, SpaceX had to divert resources to repairing that pad, which put Boca Chica on the back burner.

2 comments
1 … 297 298 299 300 301 … 477