Farmers swarming to buy used 40-year-old tractors

Buy dumb! The market for used 40-year-old tractors is booming, due to the “smart” but expensive-to-repair designs of modern computer-based tractors.

Tractors manufactured in the late 1970s and 1980s are some of the hottest items in farm auctions across the Midwest these days — and it’s not because they’re antiques. Cost-conscious farmers are looking for bargains, and tractors from that era are well-built and totally functional, and aren’t as complicated or expensive to repair as more recent models that run on sophisticated software.

“It’s a trend that’s been building. It’s been interesting in the last couple years, which have been difficult for ag, to see the trend accelerate,” said Greg Peterson, the founder of Machinery Pete, a farm equipment data company in Rochester with a website and TV show. “There’s an affinity factor if you grew up around these tractors, but it goes way beyond that,” Peterson said. “These things, they’re basically bulletproof. You can put 15,000 hours on it and if something breaks you can just replace it.”

Because of the computer software built into the new machines, a farmer can no longer fix it himself. He must call in a service truck, at high cost with long wait times. This extra cost is on top of the high cost to buy the new tractor, which cost a lot more than the used machines.

I predict that the cost for used tractors is going to continue to rise, until some smart entrepreneur realizes the market possibilities, and begins making new tractors without the bells and whistles.

First image of Ganymede’s north pole

Ganymede's north polar region

During Juno’s 24th close approach to Jupiter the spacecraft was able to take the first images ever of the north pole of Ganymede, the largest moon in the solar system. The image to the right was processed by citizen scientist Roman Tkacenko, and shows a variety of light and dark features.

The Juno science team decided for some reason to highlight a different set of images processed by citizen scientist Gerald Eichstädt, using the same data. I prefer Tkacenko’s version, because he focused in on the planet itself, making it easier to see what’s there.

In either case, however, the fuzziness of the image reminds me of planetary astronomy in my early childhood. Images like this, taken by telescopes on Earth, were the best we had of any planet beyond the Moon. Made it very hard to understand what was there, or what it meant.

More problems at Boeing, this time with military aircraft

In this article about Israel’s desire to obtain the new KC-46A airplane tankers being built by Boeing for the Air Force, it is revealed that Boeing has had numerous disturbing manufacturing problems on this particular plane.

Earlier in 2019 the U.S. air force resumed, after a two-month delay, accepting new KC-46As. That two-month delay was because of FOD (Foreign Object Debris), including tools and other metal objects, still showing up in various parts of the aircraft. This indicated a serious lapse in the management of assembly and quality control while producing these aircraft. By March, after nearly a month of effort to check out aircraft nearly ready for delivery as well as factory inspection procedures, the air force agreed to begin accepting KC-46s once more. Deliveries continued despite the recently discovered cargo lock (unreliable cargo tie down latches) problem. The Americans are now concerned about Boeing, the manufacturer while also needing the KC-46As as soon as possible. This is the same firm that is having worse problems with its new 737 Max commercial airliner.

In mid-2019 Boeing planned to deliver 36 KC-46As by the end of 2019 and later expected to meet that goal even though only 19 had been delivered by early September. At the end of the year the goal of 36 was missed but Boeing did fix the cargo lock problem and this allowed cargo to again be carried. There is one problem left with the accuracy of the remote viewing system used by the 46A boom operator. That does not prevent operation of the aircraft, just slows down refueling in some cases.

Boeing has had problems with its 737-Max commercial jet (now grounded), with the construction of the Space Launch System (SLS) for NASA (a decade behind schedule and billions over budget), and with its manned Starliner space capsule. The list of issues above for the KC-46A is equally troubling, and indicates that the management and quality control problems indicated by the other projects might very well be systemic to the entire company. Not good, not good at all.

Hat tip to reader Norm Donovan.

Update on Dream Chaser

Link here. According to Sierra Nevada, the company that is building this mini-shuttle cargo ship, they are on track to launch next year. They are also aggressively working on a Dream Chaser version that would be able to transport humans to space.

SNC has “never stopped working” on the crewed version of Dream Chaser, Lindsey said. While the company’s focus right now is getting the cargo version ready for its first flight on a United Launch Alliance (ULA) Vulcan-Centaur rocket next year, the first crewed flight “absolutely” will take place within 5 years.

“There’s interest, not necessarily from NASA, but other customers” that Lindsey expects to grow once the cargo version is flying. SNC will offer either a “taxi model” where it supplies the crew to fly it, or a “rental car model” where the customer provides the crew. It will be up to the customer to decide.

If they can get this spacecraft operational, they will join SpaceX as a leader in the reusability market, having built a ship that can be flown repeatedly on profit-making missions. In fact, it appears that the entire private American effort to get humans into space is aggressively shifting towards full reusability. SpaceX has got the first stage solved, and is also now routinely reusing its cargo Dragon capsules. It is also working to make both the upper stage (Starship) and manned capsules (crew Dragon) reusable. Sierra Nevada is in turn working on the manned spacecraft with Dream Chaser. Similarly, Blue Origin says the first stage of its New Glenn rocket will be reusable.

Those companies and nations that ignore this development (such as the Europeans Space Agency and Russia) will find themselves left far behind. Reusablity of rockets has been proven, and it lowers the cost to get to space so radically that without it you cannot compete.

House committee approves bill coordinating the government’s space weather work

The House science, space, and technology committee has approved a new bill that establishes a coordinating structure for the many government agencies involved in observing and research space weather, the material that the Sun throws at us that can affect electrical grids and communications.

A similar bill has been approved by the Senate commerce committee, but with several important differences, the most important of which is likely this provision in the House bill:

The provision requires NOAA to establish a commercial space weather data pilot program within one year of the bill’s enactment. Through that program, NOAA is to offer to enter into contracts with “one or more entities in the commercial space weather sector” to provide data that meets standards and specifications that NOAA, in consultation with the Secretary of Defense, must publish within 18 months of enactment. The data may be ground-based, ocean-based, air-based, or space-based. NOAA “may offer” to award “at least one” competitively-bid contract within 12 months of when the Integrated Strategy required in the bill, as reviewed by the National Academies, is transmitted to Congress. “If” one or more contract is awarded, NOAA is to assess the value of the pilot program and report to Congress within 4 years of enactment.

The goal of this provision is to shift construction of new space weather facilities, including satellites, from the government to private industry. Like NASA and the Defense Department, NOAA in recent decades has generally done a poor job of building satellites cheaply and quickly to maintain its in-space monitoring network. The hope is that by depending on the growing private sector, the agency can get its satellites replaced more effectively, while also energizing the space private sector.

The Senate and House bills both have only passed through committee. We shall see if the Senate agrees to add this provision to its version of the bill.

Arecibo shut temporarily due to earthquakes

The Arecibo Observatory in Puerto Rico has suspended all operations temporarily because of the swarm of earthquakes that have hit the island in the past two weeks.

The strongest of those quakes was a 6.4 temblor early in the morning of Tuesday (Jan. 7). An initial survey conducted by drone after that event found no damage to the massive radio dish or the equipment above it, an Arecibo Observatory representative said here at the 235th meeting of the American Astronomical Society on Tuesday (Jan. 7).

However, safety protocols mean that observatory personnel can’t examine the dish or its accessories until the ground stops shaking, and it’s difficult to predict when that will happen.

The observatory was about to embark on a yearlong refitting to repair damage caused by Hurricane Maria in 2017. They have set January 10th as a tentative reopen date.

Probe to visit 8 asteroids, not 7

Scientists developing the Lucy mission to visit seven Trojan asteroids that share an orbit with Jupiter have found an eighth satellite they will also be able to visit.

This first-ever mission to the Trojans was already going to break records by visiting seven asteroids during a single mission. Now, using data from the Hubble Space Telescope (HST), the Lucy team discovered that the first Trojan target, Eurybates, has a satellite. This discovery provides an additional object for Lucy to study.

“If I had to bet that one of our destinations had a satellite, it would have been this one,” said SwRI’s Hal Levison, principal investigator of the mission. “Eurybates is considered the largest remnant of a giant collision that occurred billions of years ago. Simulations show that asteroid collisions like the one that made Eurybates and its family often produce small satellites.”

The mission is targeting a 2021 launch date.

First SLS core stage completed and ready for final testing

After sixteen years of development, slowed by politics and a confused management at NASA, the first core stage of NASA’s SLS rocket is finally completed and ready for shipping to the Stennis Space Center in Mississippi for its final full test.

The heart of NASA’s first flight-ready Space Launch System heavy-lift rocket emerged from its factory in New Orleans Wednesday morning for a barge trip to the Stennis Space Center in Mississippi for an eight-minute test-firing of its space shuttle-era hydrogen-fueled engines.

The 212-foot-long (64.6-meter), 27.6-foot-wide (8.4-meter) core stage of the Space Launch System rolled out of its factory at the Michoud Assembly Facility, signaling a significant, but long-delayed milestone in the SLS program’s eight-year history. Teams loaded the core stage into NASA’s Pegasus barge to be ferried on a half-day journey to the Stennis Space Center in Mississippi.

The link has a lot of cool images of the stage. You can also find more cool images and videos of the core stage’s unveiling yesterday here.

Whether this stage will pass that eight-minute test remains unknown. And if it does, it also remains unknown whether it will be ready to fly in November 2020, sending an unmanned Orion capsule around the Moon. Either way, the cost to build that SLS rocket is approaching $25 billion, a cost that only includes two flights, one unmanned.

We could have bought a lot of Falcon Heavies for that price, and be heading for the Moon right now had we done so.

Pedestal craters in the Martian northern lowlands?

Pedestal craters on Mars?
Click for full image.

Cool image time! The photo on the right, cropped and reduced to post here, shows a cluster of really strange mesas, craters, and pits, located in Utopia Planitia, the largest and deepest plain of Mars’ northern lowlands where an intermittent ocean might have once existed.

The image was taken on October 26, 2019 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) as part of its regular image-taking program. In this case it was dubbed a “terrain sample” image, meaning that it was not specifically requested by any researcher, but was taken because they need to use the camera regularly to maintain its temperature, and thus sometime produce images over previously untouched areas, not knowing what they will find, as part of that maintenance schedule.

In this case the terrain sampled is especially intriguing. Are the upraised depressions what are called pedestal craters, created when the impact landed on what was once an icy plain, which subsequently sublimated away to leave the crater sitting high above the surrounding flats? Maybe, but this location is at 23 degrees north latitude, and research has generally found these pedestal craters at latitudes higher than 30 degrees.

Moreover, that many of these upraised depressions are not circular suggests that their formation was not impact related.

Other mysteries: Why are all the ridgelines bright? What caused the parallel white streaks to the east and west of some mesas? And if these are impact craters, why are some distorted?

If this region was once the seabed of an intermittent ocean, this fact might explain the features. Then again, it is more likely that this lowland area was once covered in ice in the far past, when the planet’s tilt was greater and the lower latitudes were actually colder than the polar regions, and thus allowed ice to build up in those lower latitudes. We might therefore be seeing the end result of an erosion/sublimation process as that ice disappeared when Mars’ inclination shifted.

Lots of questions, and no answers.

China releases data and images from Yutu-2 and Chang’e-3

Yutu-2 on the far side of the Moon
Click for full image.

The new colonial movement: To celebrate the completion of a year on the lunar surface, China has released the bulk of the data and images produced by the lander Chang’e-3 and the rover Yutu-2.

The link includes a nice gallery of images. I especially like the image to the right, cropped to post here. It shows Yutu-2 moving away from Chang’e-3 early in the mission. It also shows how truly colorless the Moon is. The rover proves this is a color image, but if it wasn’t in the shot you’d have no way of knowing.

And then there is that pitch black sky. I wonder what’s behind it.

India releases Vikram failure report

India’s space agency ISRO has released its investigation report on the failure of its lunar lander Vikram on September 7, 2019 to soft land on the Moon.

The Chandrayaan-2’s Vikram lander ended up spinning over 410 degrees, deviating from a calibrated spin of 55 degrees, and making a hard landing on the moon, according to ISRO scientists. The anomaly, which occurred during the second of four phases of the landing process, was reflected in the computer systems in the mission control room, but ISRO scientists could not intervene to correct it as the lander was on autonomous mode, using data already fed into its system before the start of the powered descent.

According to the report, they are using what was learned to incorporate changes in Chandrayaan-3, their next attempt at putting a lander and rover on the Moon, presently scheduled to launch 14 to 16 months from now. That launch date, about six months later than previous reports, also seems more realistic. Initially the agency was saying it planned to launch Chandrayaan-3 in less than a year from project inception, by November 2020, a schedule that seemed rushed and ripe for mistakes.

Webb telescope remains on schedule for March 2021 launch

Good news: According to NASA and Northrop Grumman officials, the James Webb Space Telescope remains on schedule for its March 2021 launch by an Ariane 5 rocket.

This might be the first update on Webb in years where no new delays were announced. Instead, the Space Telescope Science Institute in Maryland, which will manage the telescope, is preparing to release in two weeks its first call for research proposals.

Proposals will be due May 1, with the institute making selections later in the summer. …[I]nstitute officials said they expect to receive 1,000 to 1,600 proposals, seeking some fraction of the 6,000 hours of observing time that will be available in that initial round of observations. About 300 proposals will be selected for Cycle 1, which will begin once spacecraft commissioning is complete about six months after launch.

Let us all pray that all goes well during launch and spacecraft deployment.

SpaceX crew Dragon launch abort test delayed another week

NASA and SpaceX have delayed the launch abort test flight of the company’s crew Dragon capsule one week, to January 18, in order to allow “additional time for spacecraft processing.”

SpaceX has made it clear for the past month that their hardware is ready to go and that they could have launched by the end of December. That makes me suspect that the processing delay relates to NASA’s bureaucracy and paperwork requirements.

Dragon returns to Earth with mice and cookies baked in space

After several months docked to ISS SpaceX’s cargo Dragon returned to Earth today, bringing back forty mice send up in December for research and some cookies that were baked in space.

Researchers want to inspect the handful of chocolate chip cookies baked by astronauts in a special Zero G oven just in time for Christmas. The oven launched to the space station in November, so astronauts could pop in pre-made cookie dough provided by DoubleTree. A spokesman for the hotel chain said five cookies were baked up there, one at a time. The company plans to share details of this first-of-its-kind experiment in the coming weeks. “We made space cookies and milk for Santa this year,” NASA astronaut Christina Koch tweeted late last month from the space station, posing with one of the individually wrapped cookies.

Scientists also are getting back 40 mice that flew up in early December, including eight genetically engineered to have twice the normal muscle mass. Some of the non-mighty mice bulked up in orbit for the muscle study; others will pack it on once they’re back in the lab.

At the moment the only way to get experiments like this back from ISS is with cargo Dragon. Hopefully that will change when Sierra Nevada’s Dream Chaser mini-shuttle finally flies in the next few years.

Firefly reschedules first rocket launch for April

Capitalism in space: Due to a number of engineering issues, Firefly Aerospace has pushed back the first launch of its Alpha rocket from March to April, 2020.

In particular, figuring out the two-stage rocket’s avionics system “gave us fits,” Firefly CEO Tom Markusic told Space.com in a recent interview. That’s because the company was originally hoping to make Alpha’s flight-termination system fully autonomous, he explained.

When the vendor couldn’t qualify that advanced system in time, the vendor switched to the usual “human in the loop” system. But waiting for parts pushed back Firefly’s December 2019 launch time frame to something closer to March 2020. Firefly then chose to take a little more time for further refinements and is now aiming for April 2020 for the first launch of the 95-foot-tall (29 meters) rocket, Markusic said.

According to the article at the link, the company plans two other launches in 2020. We shall see if that pans out.

Tonight’s SpaceX launch

Capitalism in space: Tonight SpaceX is hoping to launch another 60 Starlink smallsats as part of its planned huge constellation aimed at providing internet access worldwide.

The launch is scheduled for 9:19 pm Eastern, with a 20 minute launch window. I have embedded the live stream below the fold if you wish to watch, beginning fifteen minutes before launch. Or you can go to SpaceX’s own website instead.

The launch has some significance. First, with this launch SpaceX will leap-frog a number of other satellite companies attempting to accomplish the same thing. Though it only began pursuing this project about two years ago, with this launch SpaceX will have the largest satellite constellation of any company in orbit.

Second, the first stage will be flying for the fourth time, a record, and all flown since September 2018, a mere sixteen months. That’s once every four months, a pace that far exceeds anything the space shuttle ever accomplished. Moreover, SpaceX intends to land it and reuse it again. The launch savings from this reuse guarantees that they will be able to undercut those other satellite companies when they begin offering services on the Starlink constellation. [Note: My readers corrected me: SpaceX has already launched a first stage four times.]

The company will also make another attempt to recover one fairing half.

UPDATE: The launch appears successful, including a successful landing of the first stage.

SpaceX right now is the leader in the 2020 launch race, as they are the only one to have completed a launch in 2020.
» Read more

Sunspot update: The record flatline continues

In the month of December 2019 the Sun continued its longest stretch of overall sunspot inactivity ever recorded, reaching seven months in length. At no point since the last grand minimum in the 1600s have scientists ever seen so few sunspots over so long a time period.

Below is NOAA’s December update of its graph showing the long term sunspot activity of the Sun. As I have done now every month since this webpage began in 2011, it is posted below, with annotations:
» Read more

Hubble captures giant galaxy

Giant spiral galaxy imaged by Hubble
Click for full image.

Cool image time! The above image, cropped and reduced to post here, was compiled from images taken by the Hubble Space Telescope in 2018 of one of the largest known spiral galaxies.

One of the most photogenic is the huge spiral galaxy UGC 2885, located 232 million light-years away in the northern constellation, Perseus. It’s a whopper even by galactic standards. The galaxy is 2.5 times wider than our Milky Way and contains 10 times as many stars, about 1 trillion. This galaxy has lived a quiescent life by not colliding with other large galaxies. It has gradually bulked up on intergalactic hydrogen to make new stars at a slow and steady pace over many billions of years. The galaxy has been nicknamed “Rubin’s galaxy,” after astronomer Vera Rubin (1928 – 2016). Rubin used the galaxy to look for invisible dark matter. The galaxy is embedded inside a vast halo of dark matter. The amount of dark matter can be estimated by measuring its gravitational influence on the galaxy’s rotation rate.

This majestic spiral galaxy might earn the nickname the “Godzilla Galaxy” because it may be the largest known in the local universe. The galaxy, UGC 2885, is 2.5 times wider than our Milky Way and contains 10 times as many stars.

But it is a “gentle giant,” say researchers, because it looks like it has been sitting quietly over billions of years, possibly sipping hydrogen from the filamentary structure of intergalactic space. This fuels modest ongoing star birth at half the rate of our Milky Way. In fact, its supermassive central black hole is a sleeping giant, too; because the galaxy does not appear to be feeding on much smaller satellite galaxies, it is starved of infalling gas.

There are mysteries here, many of which we are as yet entirely unaware of yet.

China now predicts more than 40 launches in 2020

The new colonial movement: China has increased its launch prediction for 2020 from 30 to more than 40 launches.

The key planned achievements:

The highlights of the space activities include the launch of China’s first Mars probe, the Chang’e-5 lunar probe, which is expected to bring moon samples back to Earth, the final step of China’s current lunar exploration program, as well as the completion of the BeiDou Navigation Satellite System constellation.

Three new types of carrier rockets including the Long March-5B, Long March-7A and Long March-8 will make their maiden flights in 2020.

It sure looks like 2020 is shaping up to possibly be the most spectacular year for space since Sputnik.

Astronaut treated for blood clot on ISS

In a first, an unnamed astronaut had been treated for a blood clot while on a six-month mission on ISS sometime in the last few years.

Ultrasound examinations of the astronauts’ internal jugular veins were performed at scheduled times in different positions during the mission. Results of the ultrasound performed about two months into the mission revealed a suspected obstructive left internal jugular venous thrombosis (blood clot) in one astronaut. The astronaut, guided in real time and interpreted by two independent radiologists on earth, performed a follow-up ultrasound, which confirmed the suspicion.

Since NASA had not encountered this condition in space before, multiple specialty discussions weighed the unknown risks of the clot traveling and blocking a vessel against anticoagulation therapy in microgravity. The space station pharmacy had 20 vials containing 300 mg of injectable enoxaparin (a heparin-like blood thinner), but no anticoagulation-reversal drug. The injections posed their own challenges – syringes are a limited commodity, and drawing liquids from vials is a significant challenge because of surface-tension effects.

The astronaut began treatment with the enoxaparin, initially at a higher dose that was reduced after 33 days to make it last until an oral anticoagulant (apixaban) could arrive via a supply spacecraft. Anticoagulation-reversing agents were also sent.

Although the size of the clot progressively shrank and blood flow through the affected internal jugular segment could be induced at day 47, spontaneous blood flow was still absent after 90 days of anticoagulation treatment. The astronaut took apixaban until four days before the return to Earth.

On landing, an ultrasound showed the remaining clot flattened to the vessel walls with no need for further anticoagulation. It was present for 24 hours after landing and gone 10 days later. Six months after returning to Earth, the astronaut remained asymptomatic.

What is not known is whether weightlessness caused the clot, or whether it would have occurred regardless. The former seems very possible as the astronaut had no history of such clots, and returned to normal almost immediately upon return to Earth. As noted at the link, more research is necessary, especially in anticipation of long interplanetary flights.

Yutu-2 completes 13th lunar day

China’s Yutu-2 lunar rover and its lander Chang’e-4 have completed their thirteenth lunar day on the far side of the Moon and have been placed in sleep mode.

During the twelve lunar day the rover traveled about 12 meters, or about 40 feet.

The rover has found materials from deep inside the moon that could help unravel the mystery of the lunar mantle’s composition and the formation and evolution of the moon and the earth. Using data obtained by the visible and near-infrared spectrometer installed on Yutu-2, Chinese scientists found that the lunar soil in the landing area of the Chang’e-4 probe contains olivine and pyroxene which came from the lunar mantle deep inside the moon.

Due to the complicated geological environment and the rugged and heavily cratered terrain on the far side of the moon, the rover drives slowly but steadily and is expected to continue traveling on the moon and make more scientific discoveries.

Darkened craters on Mars

Darkened craters on Elysium Planitia
Click for full image.

It’s time for the first cool image of 2020! The photo to the right, cropped and reduced to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on October 10, 2019. It shows a handful of darkened craters on the vast volcanic Elysium Planitia plain between the giant volcanoes Olympus Mons to the east and Elysium Mons to the north.

My first thought was that these dark craters were recent crater impacts, possibly a set of secondary impacts from a larger nearby impact. However, in looking at the archive of MRO’s high resolution camera at this location (Latitude 5.925° norther; Longitude 164.965°) I found that almost no high resolution images have been taken in this region, as shown by the overview map below to the right.
» Read more

India picks its first astronauts; confirms new lunar rover

The new colonial movement: The head of India’s space agency ISRO yesterday confirmed that their plans to build and land a rover on the Moon in 2020, while also announcing that they have chosen the first four astronauts to train for their first manned mission in 2022.

He also confirmed that the land acquisition for a second launch site is proceeding.

The astronauts, whose identity has not been revealed, will be trained by Russia.

Modern cars automatically invade your privacy

Buy dumb! According to a December 17, 2019 news story, modern cars automatically collect a vast amount of incredibly private information about their owners, especially if the owner uses the installed blue tooth phone and GPS.

[The reporter] discovered that the car was recording details about where the car was driven and parked, call logs, identification information for his phone and contact information from his phone, “right down to people’s address, emails and even photos.” In another example, Fowler bought a Chevy infotainment computer on eBay and was able to extract private information from it about whoever owned it before him, including pictures of the person the previous owner called “Sweetie.”

While GM was the subject of Fowler’s experiments, it’s not the only company collecting data on its drivers. In 2017, the U.S. Government Accountability Office looked at automakers and their data privacy policies and found that the 13 car companies it looked at are not exactly using best practices. For example, while the automakers say they obtain “explicit consumer consent before collecting data,” the GAO says they “offered few options besides opting out of all connected vehicle services to consumers who did not want to share their data.”

There is no justified ethical reason for any car company to collect and keep this information, especially without asking the owner permission to gather it. It simply does not belong to them, under any reasonable definition.

As I said, buy dumb. Better to get a used car without these invasive tools, or disable them if the car has them.

The state of the global rocket industry in 2019

With 2019 ending, it is time once again (as I did for 2016, 2017, and 2018) to review the trends in the global launch industry for the past year.

Below is my updated graph, showing the launch numbers for 2019 as well as for every year going back to 1990, just before the fall of the Soviet Union. That range I think covers all recent trends, while also giving some perspective on what happened in 2019.

The graph is worth reviewing at length, as it not only gives a sense of recent trends, it also summarizes well the history of the entire global space industry during the past thirty years. For example, it shows the transition in the U.S. in the past two decades from government-owned launchers to private rockets, a change that has revitalized the American space industry in more ways than can be counted.
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