Connect with us

Science

As it prepares to fly humans, Elon Musk's SpaceX faces its biggest challenge – Stars and Stripes

Published

 on


The company was never supposed to succeed. Even its founder gave it odds few gamblers would take — 1 in 10.

But Elon Musk decided to go all in anyway, investing some $100 million of his own money, over the protests of his friends, family and the basic logic that said a private entrepreneur with no experience in spaceflight shouldn’t start a rocket company.

The result — Space Exploration Technologies — has become one of the most improbable stories in the history of American enterprise, a combination of disruption, failure and triumph that has transformed it from a spunky start-up to an industry powerhouse with some 7,000 employees.

Now, SpaceX, as it’s commonly known, faces the most significant test since it was founded in 2002. On May 27, the California-based company is scheduled to launch two veteran NASA astronauts, Bob Behnken and Doug Hurley, to the International Space Station from the same launchpad at the Kennedy Space Center that hoisted the crew of Apollo 11 to the moon.

If all goes according to plan, the mission would herald a monumental moment in human space exploration: the first launch by a private company of people into orbit. The two astronauts will be lifted to the space station by a booster and spacecraft owned and operated by SpaceX, marking the end of the era where only government-owned spacecraft achieved such heights and adding another major step in the privatization of space. It also would become a victory for SpaceX over rival Boeing, the other company working to fly NASA’s astronauts to the space station, which has stumbled badly along the way.

If, however, SpaceX’s mission fails, it would be a tragic setback that would derail NASA’s plan to restore human spaceflight from American soil and fuel criticism that the space agency never should have outsourced such a sacred mission to the private sector.

The flight — the first of NASA astronauts from the United States since the space shuttle was retired nearly a decade ago — is the culmination of years of work by SpaceX and NASA to end America’s reliance on Russia to fly astronauts to the space station. Without a way to get astronauts to orbit, NASA has had to rely on the Russians to get to space — a fact that has embarrassed the agency but could soon come to an end if SpaceX is successful.

To get to this point, SpaceX and NASA have formed an odd-couple pairing of a 62-year-old government bureaucracy and a scrappy company still in its teens that has embraced failure as a learning tool. It has, at times, been a strained relationship — especially since SpaceX has had two of its Falcon 9 rockets blow up, one during a mission in 2015 to take cargo to the space station, another a year later while it was fueling on the launchpad ahead of an engine test to launch a commercial satellite.

Then, last year, the same Dragon spacecraft that would fly astronauts to the station exploded during a test of its abort engines.

But now, as they prepare to launch astronauts together for the first time, both NASA and SpaceX say the past failures have been investigated and remedied. Last year, SpaceX successfully completed a test mission of its Dragon spacecraft without crews to the space station. Earlier this year, it performed what NASA said was a flawless test of the abort system in flight that would carry astronauts to safety in the event of an emergency — a feature the space shuttle did not have.

Both SpaceX and NASA say that after years of hard work and testing, they are nearly ready to fly. The teams are proceeding with a “launch readiness review” on Thursday, an indication they feel confident with the date, though any number of problems — bad weather, last-minute mechanical glitches — could delay the launch.

SpaceX and NASA “are diligently working on getting the vehicles ready,” Kathy Lueders, the manager for NASA’s commercial crew program, said during a recent news conference. She said the teams were “going through all the reviews and making sure that we are ready for this important mission to safely fly. … This is a humbling job. I think we’re up to it.”

Even under ideal circumstances, launching astronauts is a dangerous and risky endeavor, but SpaceX and NASA now are doing it during the coronavirus pandemic, adding another degree of difficulty to a mission with no room for error. At least half of SpaceX’s engineers are working from home, said Gwynne Shotwell, SpaceX’s president and chief operating officer. Those that do come to the factory are keeping their distance, she said. And NASA officials have urged all but essential personnel to stay home for the mission.

For a rocket launch to go off successfully, “a million things have to go right,” Shotwell likes to say. “And only one thing has to go wrong to have a particularly bad day.”

Everyone at SpaceX knows the stakes, she said during the recent news conference.

“As far as my team goes, they don’t need to be reminded about the criticality of the work that every person is doing for this mission,” she said.

As for herself, she held her hand up just under her chin and said: “My heart is sitting right here. And I think it’s going to stay there until we get Bob and Doug back safely.”

A decade ago, it would have been unthinkable that NASA, chastened by the Challenger and Columbia space shuttle disasters that led to the deaths of 14 crew members, would entrust the lives of its astronauts to a private space company, especially one as green as SpaceX.

The company nearly died in infancy, after three consecutive launches that failed to reach orbit drained Musk’s bank account and put the company on a path to bankruptcy. It emerged triumphant after its fourth launch successfully delivered a dummy satellite to orbit in 2008 and was rescued by NASA, which awarded it a $1.6 billion contract to fly cargo and supplies to the space station a few months later. Musk, overcome, changed a log-in password to “ilovenasa.”

Then Musk took on Boeing and Lockheed Martin’s decade-long monopoly on Pentagon launch contracts. It sued the Air Force — the very customer it was trying to court — and eventually reached a settlement that allowed it to compete for launches worth hundreds of millions of dollars.

It eventually succeeded in its quest to build reusable rockets, long considered the holy grail of spaceflight that in many ways illustrates the company’s struggle — a near-impossible goal, a string of failures and then an improbable success.

SpaceX also benefited from good timing.

In 2010, President Barack Obama canceled the Constellation program, NASA’s plan to build a new fleet of rockets and spacecraft to fly astronauts to the space station and beyond. The program was way over budget and years behind schedule. The space shuttle program was near its end. And so NASA looked to the private sector to fly its astronauts — a decision that many found premature at best, reckless at worst.

“One day it will be like commercial airline travel, just not yet,” former NASA administrator Mike Griffin said at the time. “It’s like 1920. Lindbergh hasn’t flown the Atlantic, and they’re trying to sell 747s to Pan Am.”

Former NASA astronaut Garrett Reisman went to work at SpaceX in the midst of that turmoil and found the perceptions of the company to be way off.

“There was a popular perception that these were a bunch of people who didn’t really know what they were doing,” he recalled in a recent interview. “It wasn’t just a bunch of surfer dudes in a garage living in their parents’ basement and building rockets. It was a real impressive, large-scale operation.”

Since its founding, SpaceX has helped spark a renewed interest in space, and has led a growing commercial space industry that includes Jeff Bezos’s Blue Origin and Richard Branson’s Virgin Galactic. (Bezos owns The Washington Post.)

In late 2018, Virgin Galactic sent a pair of test pilots to an altitude of just over 50 miles, past where the Federal Aviation Administration says space begins. It was a straight up-and-down trip that didn’t reach orbit, but it was the first human space launch from U.S. soil since the end of the shuttle era.

Having developed a company that hopes to routinely fly tourists to space and back, Branson knows how difficult such a venture is. To get to this point, Virgin Galactic had to overcome a failure during a test flight of its SpaceShipTwo spacecraft in 2014 that killed one of the pilots.

“I have a huge amount of respect for what Elon and the SpaceX team have achieved in such a short period of time,” he said in a recent statement to The Post. “My respect is magnified because I know something of the enormous challenges involved in reinventing human spaceflight for the 21st century, but also the unparalleled satisfaction that comes with each successful milestone. While the setbacks are plentiful and painful, the breakthroughs are already transforming our relationship with the cosmos.”

Mark Cuban, one of the hosts of “Shark Tank,” the reality television show where startup companies pitch a panel of investors, said in an email to The Post that he gives Musk “a ton of credit. It’s easy to dream. It’s hard to do. He did both.”

The relationship with NASA has, at times, been strained. In 2018, senior leaders at NASA were incensed when Musk took a hit of marijuana on a show streamed on the Internet, and ordered a safety review of the company. Boeing was also supposed to be subject to a similar review, but initially got a pass. (After the company’s first flight of its Starliner spacecraft without crews went awry late last year, NASA said it would, in fact, conduct a full probe of the company’s safety culture.)

Last October, NASA administrator Jim Bridenstine, a former Republican congressman from Oklahoma who was appointed to his job by President Trump in 2017, also was upset at Musk for focusing too much on his next-generation Starship spacecraft as it was preparing to fly NASA astronauts. Bridenstine chastised him on Twitter, writing that NASA “expects to see the same level of enthusiasm focused on the investments of the American taxpayer. It’s time to deliver.”

Afterward, Musk gave Bridenstine a tour of SpaceX’s headquarters and allayed his concerns. “I think probably a couple of weeks ago we were not on the same page,” Bridenstine said at the time. “But now we are, 100 percent.”

SpaceX has always ruffled feathers, especially among traditionalists in the industry, who derided its public failures as signs that it was reckless. SpaceX, however, sees them as growing pains to be overcome.

“If there’s a test program and nothing happens in that test program, I would say it’s insufficiently rigorous,” Musk said last year. “If there hasn’t been hardware that’s blown up on a test stand, I don’t think you’ve tested it hard enough. You’ve got to push the envelope.”

One of Musk’s goals was to alter the economics of spaceflight by changing the way rockets operated. Traditionally, the first stages, or boosters, were ditched into the ocean after liftoff, never to be used again. That, Musk thought, was a waste that made spaceflight prohibitively expensive. How could an industry be sustainable if it kept throwing away the most expensive part of the rocket after a single use?

So he started trying to fly his boosters back to Earth. The effort prompted SpaceX to invent entirely new rocket components and hardware — expanding not just technical capabilities but adding to the vocabulary of space as well.

SpaceX’s Falcon 9 rockets were outfitted with “grid fins,” heat-resistant wings that helped steer the 230-foot-tall booster through the atmosphere. It had a quartet of landing legs that would unfurl just before touching down on an autonomous platform, 300 feet long by 170 feet wide, that the company called a “droneship.”

And when the rockets crashed, Musk dubbed the fireballs not explosions but “rapid unscheduled disassemblies.”

At first, there were a fair number of them, a parade of fireballs, one after the other.

In 2014, a rocket hovered over the ocean, then tipped over and scattered debris across the water’s surface. In early 2015, one slammed into the droneship — “close but no cigar” Musk tweeted at the time. A few months later, another crashed and burned.

<element>

The company eventually released a blooper reel of its rockets blowing up, with a caption for one crash that read, “Well, technically, it did land … just not in one piece.”

To some in the space industry, the embrace of failure was refreshing. When NASA veterans visited Reisman at SpaceX, he said they’d tell him “this place reminds me a lot of what NASA was like during Apollo. So it was kind of like it was almost like taking NASA back to its roots.”

Then, in December 2015, another Falcon 9 landed just as an ominous thunder cascaded over Cape Canaveral.

Another explosion, Musk thought.

But this time, when the smoke cleared, there was no fire. Just a rocket standing triumphantly on a landing pad on the Cape. The sound Musk heard was a sonic boom, not a detonation.

“You have to learn those hard lessons,” Shotwell said. “I think sometimes the aerospace industry shies away from failure in the development phase. It looks bad politically. It’s tough. And the media certainly makes a lot of failures. But, candidly, that’s the best way to learn — to push your systems to their limit, which includes your people systems and your processes, and learn where you’re weak and make things better.”

Let’s block ads! (Why?)



Source link

Continue Reading

Science

You’ve Seen the New Image of the Milky Way’s Black Hole – Now Hear It! – SciTechDaily

Published

 on


This is a sonification — translation into sound — of the latest image from the Event Horizon Telescope (EHT) of the supermassive black hole at the center of the Milky Way called Sagittarius A* (Sgr A*). Using a radar-like scan, the sonification begins at the 12 o’clock position and sweeps clockwise. Changes in the volume represent the differences in brightness the EHT observed around the event horizon of Sgr A*. The material that is closer to the <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

black hole
A black hole is a place in space where the pull of gravity is so strong not even light can escape it. Astronomers classify black holes into three categories by size: miniature, stellar, and supermassive black holes. Miniature black holes could have a mass smaller than our Sun and supermassive black holes could have a mass equivalent to billions of our Sun.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>black hole and hence moving faster corresponds to higher frequencies of sound. This sonification was processed in a special way to allow a listener to hear the data in 3D stereo sound, in which the sounds seem to start directly ahead and then move clockwise to one ear and then the other as the sweep is made.

[embedded content]

About the Sound:

  • This is a radar-like scan, starting from 12 o’clock and moving clockwise.
  • The brightness controls the volume and the radial position controls the frequencies that are present.
  • The emission from material closer to the black hole (which orbits faster) is mapped to higher frequencies.
  • The sound is rendered in binaural audio. When listened to with headphones, the sound will appear to start directly in front of you and then move clockwise all the way around your head.
  • Listen for the three bright regions at about 1, 5, and 9 o’clock, as well as the very low tones indicating fainter light from outside the main ring.

Sonification Credit: <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

NASA
Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It's vision is &quot;To discover and expand knowledge for the benefit of humanity.&quot;

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>NASA/CXC/SAO/K.Arcand, SYSTEM Sounds (M. Russo, A. Santaguida);

Image Credit: Radio: EHT Collaboration; X-ray (NASA/CXC/SAO); Infrared (NASA/HST/STScI)

Adblock test (Why?)



Source link

Continue Reading

Science

When Is The Next Total Lunar Eclipse ‘Blood Moon?’ The Coming Once-In-430 Years ‘Twin’ Totality Will Be The Longest Until 2029 – Forbes

Published

 on


If you’re reading this having just seen the spectacular sight of the “Blood Moon” (or perhaps you didn’t because of cloud) it’s likely that there’s only one question on your mind: when’s the next one?

The next total lunar eclipse is on Monday, November 7 and into Tuesday, November 8, 2022. That’s in just 145 days! It will be best seen from west coast of North America, with Australia and southeast Asia also in a good position.

Like the events of May 15-16 it will also features an 84-minute totality (it’s actually four seconds longer). That’s highly unusual. According to Timeanddate.com, it’s the most balanced pair of lunar eclipses in 430 years.

Here’s a simulation of exactly what it will look like and here’s an interactive Google Map.

November’s eclipse will be just as long as what North America just experienced, with lunar totality seeing the full “Frosty” or “Beaver” Moon turn a spectacular reddish color for 84 minutes.

That kind of duration of totality won’t be topped until a 102 minute totality on June 26, 2029.

A total lunar eclipse can be seen from any given location every 2.5 years, on average, and that plays out in the 2020s. The following total lunar eclipse is on March 13-14, 2025.

North America will once again get a good view, though it comes at a time of year when cloud will likely be a big problem.

It will almost be part of a “tetrad,” which is when four consecutive eclipse seasons—which are about six months apart—each contain a total lunar eclipse. However, the final event is a bit of a celestial letdown:

  • March 14, 2025: Total lunar eclipse
  • September 7, 2025: Total lunar eclipse
  • March 3, 2026: Total lunar eclipse
  • August 28, 2026: Partial lunar eclipse

However, with 93% of the Moon covered by the Earth’s shadow at the peak even that will be a sight to behold.

What is an ‘eclipse season?’

Every 173 days (six months), for between 31 and 37 days, the Moon is lined-up perfectly to intersect the ecliptic—the apparent path of the Sun through our daytime sky and the plane of Earth’s orbit around the Sun.

The result, of course, is a short season during which two—and occasionally three—solar and lunar eclipses can occur.

Disclaimer: I am the editor of WhenIsTheNextEclipse.com

Wishing you clear skies and wide eyes.

Adblock test (Why?)



Source link

Continue Reading

Science

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

Published

 on


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.

<img data-attachment-id="10398" data-permalink="https://everydayastronaut.com/starlinksatsloaded/" data-orig-file="https://everydayastronaut.com/wp-content/uploads/2019/11/starlinksatsloaded.jpg" data-orig-size="1282,1920" data-comments-opened="1" data-image-meta=""aperture":"0","credit":"","camera":"","caption":"","created_timestamp":"0","copyright":"","focal_length":"0","iso":"0","shutter_speed":"0","title":"","orientation":"0"" data-image-title="starlinksatsloaded" data-image-description data-image-caption="

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

Adblock test (Why?)



Source link

Continue Reading

Trending