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Is There An Apollo 14 Moon Tree Near You? – Universe Today

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50 years ago this week, the Apollo 14 crew flew their mission to the Moon. Alan Shepard and Edgar Mitchell were the third pair of astronauts to walk on the lunar surface. They conducted two moonwalks in the Frau Mauro highlands, collecting rocks and setting up science experiments, as well as broadcasting the first color TV images from the Moon.

Meanwhile, Stuart Roosa remained in orbit as the Command Module pilot. But Roosa wasn’t alone while circling above the Moon.  

The crew of the Apollo 14 lunar landing mission: Alan B. Shepard Jr., center, commander; Stuart A. Roosa, left, command module pilot; and Edgar D. Mitchell, lunar module pilot. The Apollo 14 emblem is in the background. Credit: NASA

In his personal preference kit, Roosa brought along five varieties of tree seeds, about 400 seeds in total. After the mission, those seeds were germinated and grown, with between 200-300 seedlings and saplings planted across the country and around the world, between 1975 and the early 1980s. But exactly where all those “Moon Trees” were planted has been lost. NASA has been trying to locate and document any of those trees, and find out whether any are still living.

“It’s possible you might live near a Moon tree and you don’t know about it,” said NASA scientist Dave Williams, who works at Goddard Spaceflight Center.

Williams has documented the locations of about 80 of these trees. If anyone knows of a Moon Tree or remembers attending a planting ceremony for a Moon Tree not already on his list, Williams would love to hear from you.   

Branches of a Sycamore Moon Tree located at the University of Arizona. Image courtesy of Geoff Notkin.

The story of the Moon Trees started before Stuart Roosa became an astronaut. He had served as a smoke jumper for the US Forest Service, parachuting into areas to help fight wildfires. After Roosa was chosen to be part of Apollo 14, the Forest Service approached him and asked if he’d consider being part of a small experiment: would he bring tree seeds along to the Moon, and after the flight, the Forest Service would oversee the project to see if the seeds would germinate after being in weightlessness.

“The seeds were kept in a container about the size of a soda can, and it was sealed so they were never in the vacuum of space,” Williams said. “They also had seeds that remained back on Earth, so they did plan a type of controlled experiment, but no one really expected there to be any difference in the seeds.”

However, everything brought back from the Moon had to be decontaminated in a vacuum chamber, and during the decontamination process, the seed cannister burst open, with the seeds scattering about – and so the seeds actually were exposed to vacuum – which was not part of the original experiment!

“The seeds were germinated and grown in greenhouses,” Williams said, “and in some sense they did do a science experiment, but it was mainly a public relations kind of thing.”

The Sycamore Moon Tree at Kennedy Space Center in Florida. Credit: NASA.

The seedlings and saplings were given to congressional members and foreign ambassadors. They were planted at town halls, parks and libraries, as well as at NASA centers, universities and state capitals across the US.

There were five different types of tree seeds: Loblolly Pine, Sycamore, Sweetgum, Redwood, and Douglas Fir. A Loblolly Pine, which has since died, was planted at the White House. Trees were planted in Brazil, Switzerland, and presented to the Emperor of Japan, among others.

The Moon Tree clone at Washington Square in Philadelphia, which was planted in 2011 and has since been removed. This picture was taken in 2017. Credit: Nancy Atkinson

The first Moon Tree ever planted was a Sycamore at Washington Square in Philadelphia, Pennsylvania in 1975 in preparation for the US Bicentennial in 1976. The original tree planted there died, but a clone was planted in 2011; the clone was not thriving and was removed in 2019. The original plaque still remains, with plans to plant another clone tree.

There were plans to commemorate the 50th anniversary of the Apollo 14 flight at Goddard Space Flight Center, where another Moon Tree is planted, but the plans fell through due to the pandemic. 

From personal experience, seeing and touching a Moon Tree is a wonderful experience, which beautifully provides a connection to both the Apollo program and also the effect it had on our appreciation of our own planet Earth. I’ve had the chance to visit three Moon Trees: one at Kennedy Space Center, the clone in Philadelphia a few years ago, and another Sycamore that stands on the University of Arizona campus in Tucson, just outside of the Flandrau Science Center & Planetarium. The tree was shown to me by Geoff Notkin, author, adventurer and co-star of the Discovery Channel’s Meteorite Men series. Notkin is also the president of the National Space Society and is CEO of Aerolite Meteorites Inc, a company that provides meteorite specimens to researchers, museums, and collectors worldwide.

“I’ve long been fascinated by the Moon Tree story, and after I moved to Tucson, I was almost speechless to discover there was a Moon Tree in my adopted home town!” Notkin said. He agreed that seeing a Moon Tree is an experience in itself.

Geoff Notkin with the Moon Tree, several years ago at the University of Arizona. Image courtesy of Geoff Notkin.

“It was almost a metaphysical experience to put my hand on the trunk of the tree, which was grown from a seed that was flown to the Moon,” he said. “I have held any number of space rocks in my hands – both NASA samples and lunar meteorites — and I have to say, none of them were as thrilling as touching the Moon Tree! Something in me connected deeply with Stuart Roosa’s story and the idea to take these seeds with him to the Moon.”

Notkin is working on a book about the Moon Trees and Stuart Roosa’s story (Roosa, sadly, passed away in 1994), in attempt to tell the entire tale and possibly locate more of the trees. But the hunt for more Moon Trees might be as challenging as hunting for meteorites. Without good records of where all the trees were planted, the whereabouts of the trees today are mostly unknown.

“As space exploration enthusiasts, we’re usually very caught up in the technical aspects of spaceflight,” Notkin told me. “But to me, it is so mesmerizing that there is a tangible natural history result from this experiment. These trees are out there – all around the world – and in their own quiet way, they are celebrating the might of the Apollo program.”

If you know of any additional Moon Trees that aren’t already listed here, or if you recall attending a tree planting ceremony for a Moon Tree, see this NASA website on how to get your tree documented. If you’ve got a Moon Tree story, we’d love to hear it! Share your story in the comments below or on Universe Today’s social media sites.  

Lead image caption: The plaque at Washington Square in Philadelphia commemorating the planting of the first Moon Tree.

The author by the Moon Tree at the University of Arizona in 2017. Image taken by Geoff Notkin.

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Starlink Group 4-13 | Falcon 9 Block 5 – Everyday Astronaut

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Lift Off Time
May 13, 2022 – 22:07 UTC | 15:07 PDT
Mission Name
Starlink Group 4-13; the fifteenth launch to Starlink Shell 4
Launch Provider
(What rocket company launched it?)
SpaceX
Customer
(Who paid for this?)
SpaceX
Rocket
Falcon 9 Block 5, B1063-5; 108.20 day turnaround
Launch Location
Space Launch Complex 4 East (SLC-4E), Vandenberg Space Force Base, California, USA
Payload mass
~16,250 kg (~35,800 lb) (53 x 307 kg, plus dispenser)
Where did the satellites go?
Starlink Shell 4; 540 km circular low-Earth orbit (LEO); initial orbit: 315 x 305 km at 53.22°
Did they attempt to recover the first stage?
Yes
Where did the first stage land?
B1063 successfully landed 642 km downrange on Of Course I Still Love You

Tug: Debra C; Support: GO Quest

Did they attempt to recover the fairings?
The fairing halves were recovered from the water ~654 km downrange by NRC Quest
Were these fairings new?
No, both fairing halves were flight proven
This was the:
– 153rd Falcon 9 launch
– 93rd Falcon 9 flight with a flight proven booster
– 97th re-flight of a booster
– 18th re-flight of a booster in 2022
– 119th booster landing

– 45th consecutive landing (a record)
– 19th launch for SpaceX in 2022
– 23rd SpaceX launch from SLC-4E
– 53rd orbital launch attempt of 202
2
Where to watch
Official Replay

How Did It Go?

SpaceX’s Starlink Group 4-13 mission successfully launched 53 Starlink satellites atop a Falcon 9 rocket. The Falcon 9 lifted off from Space Launch Complex 4 East (SLC-4E), at the Vandenberg Space Force Base, in California, United States. Starlink Group 4-13 marked the 44th operational Starlink mission, boosting the total number of Starlink satellites launched to 2,547, of which 2,300 are in orbit around the Earth. Starlink Group 4-13 marked the 15th launch to the fourth Starlink shell; roughly 30 launches will be required to fill this shell.

Starlink is SpaceX’s internet communication satellite constellation. The low-Earth orbit constellation will deliver fast, low-latency internet service to locations where ground-based internet is unreliable, unavailable, or expensive. The first phase of the constellation consists of five orbital shells.

Starlink is currently available in certain regions, allowing anyone in approved regions to order or preorder. After 28 launches SpaceX achieved near-global coverage, but the constellation will not be complete until ~42,000 satellites are in orbit. Once Starlink is complete, the venture is expected to profit $30-50 billion annually. This profit will largely finance SpaceX’s ambitious Starship program, as well as Mars Base Alpha.

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A stack of 60 Starlink sattelites prior to be encapsulated into Falcon 9’s payload fairing. (Credit: SpaceX)

” data-medium-file=”https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-200×300.jpg” data-large-file=”https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-684×1024.jpg” width=”684″ height=”1024″ src=”https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-684×1024.jpg” alt=”Starlink satellites, satellite dispenser.” class=”wp-image-10398″ srcset=”https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-684×1024.jpg 684w, https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-200×300.jpg 200w, https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-768×1150.jpg 768w, https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-1026×1536.jpg 1026w, https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-1200×1797.jpg 1200w, https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-380×569.jpg 380w, https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-800×1198.jpg 800w, https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded-1160×1737.jpg 1160w, https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded.jpg 1282w” sizes=”(max-width: 684px) 100vw, 684px”>

A stack of 60 Starlink V1.0 satellites prior to be encapsulated into Falcon 9’s payload fairing. (Credit: SpaceX)

Each Starlink V1.5 satellite has a compact design and a mass of 307 kg. SpaceX developed a flat-panel design, allowing them to fit as many satellites as possible into the Falcon 9’s 5.2 meter wide payload fairing. Due to this flat design, SpaceX is able to fit up to 60 Starlink satellites and the payload dispenser into the second stage, while still being able to recover the first stage. This is near the recoverable payload capacity of the Falcon 9 to LEO, around 16 tonnes. 

As small as each Starlink satellite is, each one is packed with high-tech communication and cost-saving technology. Each Starlink satellite is equipped with four phased array antennas, for high bandwidth and low-latency communication, and two parabolic antennas. The satellites also include a star tracker, which provides the satellite with attitude data, ensuring precision in broadband communication. 

Each Starlink V1.5 satellite is also equipped with an inter-satellite laser communication system. This allows each satellite to communicate directly with other satellites, not having to go through ground stations. This reduces the number of ground stations needed, allowing coverage of the entire Earth’s surface, including the poles.

The Starlink satellites are also equipped with an autonomous collision avoidance system, which utilizes the US Department of Defense (DOD) debris tracking database to autonomously avoid collisions with other spacecraft and space junk. 

To decrease costs, each satellite has a single solar panel, which simplifies the manufacturing process. To further cut costs, Starlink’s propulsion system, an ion thruster, uses krypton as fuel, instead of xenon. While the specific impulse (ISP) of krypton is significantly lower than xenon’s, it is far cheaper, which further decreases the satellite’s manufacturing cost.

Ion Power

Each Starlink satellite is equipped with the first Hall-effect krypton-powered ion thruster. This thruster is used for both ensuring the correct orbital position, as well as for orbit raising and orbit lowering. At the end of the satellite’s life, this thruster is used to deorbit the satellite.

A satellite constellation is a group of satellites that work in conjunction for a common purpose. Currently, SpaceX plans to form a network of 11,716 satellites; however, in 2019 SpaceX filed an application with the Federal Communication Commission (FCC) for permission to launch and operate an additional 30,000 satellites as part of phase 2 of Starlink. To put this number of satellites into perspective, this is roughly 20 times more satellites than were launched before 2019. 

Of the initial ~12,000 satellites, ~4,400 would operate on the Ku and Ka bands, with the other ~7,600 operating on the V-Band. 

Due to the vast number of Starlink satellites, many astronomers are concerned about their effect on the night sky. However, SpaceX is working with the astronomy community and implementing changes to the satellites to make them harder to see from the ground and less obtrusive to the night sky. SpaceX has changed how the satellites raise their orbits and, starting on Starlink V1.0 L9, added a sunshade to reduce light reflectivity. These changes have already significantly decreased the effect of Starlink on the night sky.

Inclination (°) Orbital Altitude (km) Number of Satellites
Shell 1 53.0 550 1,584
Shell 2 70.0 570 720
Shell 3 97.6 560 348
Shell 4 53.2 540 1,584
Shell 5 97.6 560 172
Orbital Shells

Shell 1

The first orbital shell of Starlink satellites consists of 1,584 satellites in a 53.0° 550 km low-Earth orbit. Shell 1 consists of 72 orbital planes, with 22 satellites in each plane. This shell is currently near complete, with occasional satellites being replaced. The first shell provides coverage between roughly 52° and -52° latitude (~80% of the Earth’s surface), and will not feature laser links until replacement satellites launch after 2021.

Shell 2

Starlink’s second shell will host 720 satellites in a 70° 570 km orbit. These satellites will significantly increase the coverage area, which will make the Starlink constellation cover around 94% of the globe. SpaceX will put 20 satellites in each of the 36 planes in the third shell. This shell is currently being filled, along with Shell 4.

Shell 3

Shell 3 will consist of 348 satellites in a 97.6° 560 km orbit. SpaceX deployed 10 laser link test satellites into this orbit on their Transporter-1 mission to test satellites in a polar orbit. SpaceX launched an additional three satellites to this shell on the Transporter-2 mission. On April 6, 2021, Gwynne Shotwell said that SpaceX will conduct regular polar Starlink launches in the summer, but this shell is now the lowest priority, and is expected to be the last filled. All satellites that will be deployed into this orbit will have inter-satellite laser link communication. Shell 4 will have six orbital planes with 58 satellites in each plane.

Shell 4

The fourth shell will consist of 1,584 satellites in a 540 km 53.2° LEO. This updated orbital configuration will slightly increase coverage area and will drastically increase the bandwidth of the constellation. This shell will also consist of 72 orbital planes with 22 satellites in each plane. This shell is currently being filled alongside Shell 2.

Shell 5

The final shell of Phase 1 of Starlink will host 172 satellites in another 97.6° 560 km low-Earth polar orbit. Shell 5 will also consist purely of satellites with laser communication links; however, unlike Shell 3, it will consist of four orbital planes with 43 satellites in each plane.

Shell 6

The sixth orbital shell of Starlink satellites is permitted to consist of 2,493 satellites in a 42° 335.9 km LEO. This large number of satellites will decrease latency and increase bandwidth for lower latitudes.

Shell 7

The seventh Starlink shell permits SpaceX to deploy 2,478 satellites into a 48° 340.8 km low-Earth orbit. These satellites will further decrease latency and increase bandwidth for lower latitudes.

Shell 8

The final shell of Starlink Phase 2 allows SpaceX to deploy 2,547 satellites in a 53° 345.6 km orbit.

SpaceX has until March of 2024 to complete half of phase 1 and must fully complete Phase 1 by March of 2027. Phase 2 must be half complete by November of 2024, and be finished by November of 2027. Failure to do so could result in SpaceX losing its dedicated frequency band.

What Is Falcon 9 Block 5?

The Falcon 9 Block 5 is SpaceX’s partially reusable two-stage medium-lift launch vehicle. The vehicle consists of a reusable first stage, an expendable second stage, and, when in payload configuration, a pair of reusable fairing halves.

First Stage

The Falcon 9 first stage contains 9 Merlin 1D+ sea level engines. Each engine uses an open gas generator cycle and runs on RP-1 and liquid oxygen (LOx). Each engine produces 845 kN of thrust at sea level, with a specific impulse (ISP) of 285 seconds, and 934 kN in a vacuum with an ISP of 313 seconds. Due to the powerful nature of the engine, and the large amount of them, the Falcon 9 first stage is able to lose an engine right off the pad, or up to two later in flight, and be able to successfully place the payload into orbit.

The Merlin engines are ignited by triethylaluminum and triethylborane (TEA-TEB), which instantaneously burst into flames when mixed in the presence of oxygen. During static fire and launch the TEA-TEB is provided by the ground service equipment. However, as the Falcon 9 first stage is able to propulsively land, three of the Merlin engines (E1, E5, and E9) contain TEA-TEB canisters to relight for the boost back, reentry, and landing burns.

Second Stage

The Falcon 9 second stage is the only expendable part of the Falcon 9. It contains a singular MVacD engine that produces 992 kN of thrust and an ISP of 348 seconds. The second stage is capable of doing several burns, allowing the Falcon 9 to put payloads in several different orbits.

For missions with many burns and/or long coasts between burns, the second stage is able to be equipped with a mission extension package. When the second stage has this package it has a grey strip, which helps keep the RP-1 warm, an increased number of composite-overwrapped pressure vessels (COPVs) for pressurization control, and additional TEA-TEB.

Falcon 9 Block 5 launching on the Starlink V1.0 L27 mission (Credit: SpaceX)

Falcon 9 Booster

The booster that supported Starlink Group 4-13 is B1063. As the booster had supported 4 previous flights, its designation for Starlink Group 4-13 is B1063-5. This changed to B1063-6 upon successful landing.

B1063’s missions Launch Date (UTC) Turnaround Time (Days)
Sentinel-6 November 21, 2020 17:17 N/A
Starlink V1.0 L28 May 26, 2021 18:59 186.07
DART November 24, 2021 06:21 181.47
Starlink Group 4-11 February 25, 2022 17:12 62.45
Starlink Group 4-13 May 13, 2022 22:07 108.20

Following stage separation, the Falcon 9 conducted two burns. These burns softly touched down the booster on SpaceX’s autonomous spaceport drone ship Of Course I Still Love You.

falcon 9 booster, landing, drone ship
Falcon 9 landing on Of Course I Still Love You after launching Bob and Doug (Credit: SpaceX)

Falcon 9 Fairings

The Falcon 9’s fairing consists of two dissimilar reusable halves. The first half (the half that faces away from the transport erector) is called the active half, and houses the pneumatics for the separation system. The other fairing half is called the passive half. As the name implies, this half plays a purely passive role in the fairing separation process, as it relies on the pneumatics from the active half.

Both fairing halves are equipped with cold gas thrusters and a parafoil which are used to softly touch down the fairing half in the ocean. SpaceX used to attempt to catch the fairing halves, however, at the end of 2020 this program was canceled due to safety risks and a low success rate. On Starlink Group 4-13, SpaceX recovered the fairing halves from the water with their recovery vessel NRC Quest.

In 2021, SpaceX started flying a new version of the Falcon 9 fairing. The new “upgraded” version has vents only at the top of each fairing half, by the gap between the halves, whereas the old version had vents placed spread equidistantly around the base of the fairing. Moving the vents decreases the chance of water getting into the fairing, making the chance of a successful scoop significantly higher.

All times are approximate

HR/MIN/SEC EVENT
00:38:00 SpaceX Launch Director verifies go for propellant load
00:35:00 RP-1 (rocket grade kerosene) loading underway
00:35:00 1st stage LOX (liquid oxygen) loading underway
00:16:00 2nd stage LOX loading underway
00:07:00 Falcon 9 begins engine chill prior to launch
00:01:00 Command flight computer to begin final prelaunch checks
00:01:00 Propellant tank pressurization to flight pressure begins
00:00:45 SpaceX Launch Director verifies go for launch
00:00:03 Engine controller commands engine ignition sequence to start
00:00:00 Falcon 9 liftoff

All times are approximate

HR/MIN/SEC EVENT
00:01:12 Max Q (moment of peak mechanical stress on the rocket)
00:02:30 1st stage main engine cutoff (MECO)
00:02:34 1st and 2nd stages separate
00:02:40 2nd stage engine starts (SES-1)
00:02:45 Fairing deployment
00:06:25 1st stage entry burn start
00:06:44 1st stage entry burn complete
00:08:10 1st stage landing burn start
00:08:33 1st stage landing
00:08:46 2nd stage engine cutoff (SECO-1)
00:53:40 2nd stage engine starts (SES-2)
00:53:41 2nd stage engine cutoff (SECO-2)
01:02:42 Starlink satellites deploy

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Supermassive black hole at the center of our galaxy revealed – Earth.com

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By use of extremely powerful telescopes, scientists had previously seen stars orbiting around something invisible, compact, and very massive at the center of our galaxy. This object – known as Sagittarius A* (Sgr A*) – appears to be a huge black hole located 27,000 light-years away from Earth. Now, for the fist time, astrophysicists have managed to capture an image of this supermassive black hole – which is four million times more massive than our sun – at the heart of the Milky Way.

Although the black hole itself is invisible, glowing gas around it reveals a tell-tale signature: a dark central region – called a “shadow”- surrounded by a bright ring-like structure, which is the light bent by the enormous gravity of the black hole.

“For decades, astronomers have wondered what lies at the heart of our galaxy, pulling stars into tight orbits through its immense gravity,” said Michael Johnson, an astrophysicist at Harvard University. “With the image [captured by Event Horizon Telescope or EHT], we have zoomed in a thousand times closer than these orbits, where the gravity grows a million times stronger. At this close range, the black hole accelerates matter to close to the speed of light and bends the paths of photons in the warped (space-time).”

“We were stunned by how well the size of the ring agreed with predictions from Einstein’s theory of general relativity,” added EHT Project Scientist Geoffrey Bower. “These unprecedented observations have greatly improved our understanding of what happens at the very center of our galaxy and offer new insights on how these giant black holes interact with their surroundings.”

To image the black hole, scientists used the powerful EHT, which linked together eight radio observatories across the planet to form a single, “Earth-sized” virtual telescope. By employing this groundbreaking technology to observe Sgr A* on multiple nights and collect data for long periods of time, the researchers created a library of millions of images which then needed to be interpreted theoretically to assess what type of astronomical objects they had in fact detected.

“To understand how the EHT has produced an image of Sgr A* one can think of producing a picture of a mountain peak based on a time-lapse video,” explained Luciano Rezzolla, a theoretical astrophysicist at Goethe University Frankfurt. “While most of the time the peak will be visible in the time-lapse video, there are times when it is not because it is obscured by clouds. On average, however, the peak is clearly there. Something similar is true also for Sgr A*, whose observations lead to thousands of images which have been collected in four classes and then averaged according to their properties. The end result is a clear first image of the black hole at the center of the Milky Way.” 

This breakthrough discovery follows EHT’s 2019 release of the first image of a black hole, called M87*, located at the center of the more distant Messier 87 galaxy. Even though our galaxy’s black hole is over a thousand times smaller than M87*, the two astronomical objects look amazingly similar. Now, the scientists can compare the two to shed more light on how gas behaves around supermassive black holes. 

“Now we can study the differences between these two supermassive black holes to gain valuable new clues about how this important process works,” said EHT scientist Keiichi Asada. “We have images for two black holes — one at the large end and one at the small end of supermassive black holes in the Universe — so we can go a lot further in testing how gravity behaves in these extreme environments than ever before.”

A detailed description of Sgr A* is published in the Astrophysical Journal Letters.

Image Credit: Younsi, Fromm, Mizuno & Rezzolla (University College London, Goethe University Frankfurt

—-

By Andrei Ionescu, Earth.com Staff Writer

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SpaceX launches Starlink 4-15 mission, expands booster fleet – NASASpaceFlight.com – NASASpaceflight.com

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SpaceX launches Starlink 4-15 mission, expands booster fleet – NASASpaceFlight.com

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