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SpaceX modifies Starlink network design as another 60 satellites gear up for launch – Spaceflight Now

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Artist’s illustration of the distribution of satellites in SpaceX’s Starlink network. Credit: SpaceX

Another 60 Starlink satellites are ready for launch Wednesday to beam Internet signals to future SpaceX consumers as the company seeks regulatory approval to fly all 4,400 relay stations in the network’s first phase of deployment at lower altitudes than previously planned.

SpaceX’s Starlink network is a multibillion-dollar program aimed at blanketing the planet in broadband connectivity, serving a wide range of consumers in homes, businesses, schools and hospitals. The network, which could eventually number thousands of satellites, is also designed to provide connectivity to airplanes and ships, and the U.S. military is testing the Starlink service to gauge its military usefulness.

“With performance that far surpasses that of traditional satellite Internet, and a global network unbounded by ground infrastructure limitations, Starlink will deliver high speed broadband internet to locations where access has been unreliable, expensive, or completely unavailable,” SpaceX says.

SpaceX has launched 360 Starlink satellites on six Falcon 9 rockets since last May. Another 60 are scheduled for launch Wednesday at 3:37 p.m. EDT (1937 GMT) from pad 39A at NASA’s Kennedy Space Center in Florida.

Sporting a previously-flown first stage and a recycled payload fairing, the Falcon 9 rocket will be fueled with super-chilled, densified kerosene and liquid oxygen propellants beginning around 35 minutes prior to liftoff.

There is a 90 percent chance of acceptable weather conditions for launch Wednesday, according to an outlook issued by the U.S. military’s 45th Weather Squadron at Cape Canaveral. SpaceX says it moved up the launch by a day from Thursday to take advantage of the good weather forecast.

The Falcon 9’s engine controller will command ignition of the rocket’s nine Merlin 1D main engines around three seconds before liftoff. The engines will power up to full throttle and hold-down clamps will open to allow the 229-foot-tall (70-meter) launcher to take off from pad 39A with 1.7 million pounds of thrust.

Heading toward the northeast, the Falcon 9 rocket will surpass the speed of sound in about one minute, then shut down its first stage engines roughly two-and-a-half minutes into the mission. The 15-story first stage booster will separate and attempt a propulsive landing on SpaceX’s drone ship parked several hundred miles northeast of Cape Canaveral in the Atlantic Ocean.

The Falcon 9’s second stage will fire its single Merlin engine to power the 60 quarter-ton Starlink satellites into orbit. Early in the second stage burn, the rocket will jettison its clamshell-like nose shroud once it has climbed above the dense, lower layers of the atmosphere.

SpaceX’s two fairing recovery boats will also be on station in the Atlantic Ocean east of Charleston, South Carolina, to try to snare the two fairing halves in giant nets for potential reuse on a future mission.

The fairing on Wednesday’s mission previously launched last August with the Israeli Amos 17 communications satellite, and were recovered at sea. The first stage assigned to Wednesday’s flight is a veteran of three previous launches and landings, including on the unpiloted test flight of SpaceX’s Crew Dragon capsule in March 2019.

A plume of exhaust erupts from pad 39A’s flame trench at 12 p.m. EDT (1600 GMT) Friday during SpaceX’s static fire test. Credit: William Harwood/CBS News

If all goes according to plan, the Falcon 9’s second stage will shut down its engine nearly nine minutes after liftoff, injecting the Starlink satellites into a preliminary elliptical orbit ranging more than 200 miles (300 kilometers) above Earth.

The 60 Starlink spacecraft will deploy from the Falcon 9 upper stage all at once over the North Atlantic Ocean around 14 minutes into the mission.

Each of the quarter-ton Starlink satellites is expected to unfurl a solar array wing and activate a krypton ion propulsion drive to begin climbing to an operational orbit 341 miles (550 kilometers) in altitude, where they will join hundreds other Starlink nodes launched since last May.

SpaceX has modified the architecture of the Starlink network several times. Most recently, SpaceX submitted an application to the Federal Communication Commission on Friday proposing to operate more satellites in lower orbits than the FCC previously authorized.

The first phase of the Starlink network will include 1,584 satellites orbiting 341 miles (550 kilometers) above Earth in planes inclined 53 degrees to the equator. That part of the constellation, which SpaceX intends to launch through the end of the year, remains unchanged in SpaceX’s application.

SpaceX previously had regulatory approval from the FCC to operate another 2,825 satellites in higher orbits between 690 miles (1,110 kilometers) and 823 miles (1,325 kilometers) in altitude, in orbital planes inclined 53.8, 70, 74 and 81 degrees to the equator.

The modified plan submitted to the FCC by SpaceX foresees Ku-band and Ka-band satellites in the next phase of the Starlink network all operated at altitudes between 335 miles (540 kilometers) and 354 miles (570 kilometers) at inclinations of 53.2, 70 and 97.6 degrees.

The application covers 4,408 Starlink satellites, one fewer than SpaceX envisioned under the previous architecture.

In documentation submitted Friday to the FCC, SpaceX said lower altitude will put the satellites closer to Starlink consumers and allow the network “to provide low-latency broadband to unserved and underserved Americans that is on par with service previously only available in urban areas.”

The change will also improve Starlink service for U.S. government users in polar regions and allow for more rapid deployment of the network, SpaceX said.

Flying Starlink satellites in lower orbits will help ensure they re-enter the atmosphere a shorter time in case of failure. And the spacecraft will broadcast signals at reduced power levels because they are closer to Earth, which SpaceX said will allow the Starlink fleet to be compliant with limits to reduce radio interference with other satellite and terrestrial wireless networks.

Last week’s application to modify SpaceX’s FCC license is the latest in a series of adjustments to the Starlink architecture. Before the first launch of 60 Starlink satellites last year, SpaceX received FCC approval to migrate the positions of the fleet’s first 1,584 satellites from 714 miles (1,150 kilometers) to 341 miles (550 kilometers).

In December, the FCC granted a SpaceX request to reconfigure the distribution of the Starlink satellites in different orbital planes. SpaceX said that request was intended to expand Starlink coverage faster around the United States without the need for more satellites.

SpaceX wrote in the FCC filing Friday that the Starlink network remains on track to begins serving American consumers this year.

A view of 60 Starlink satellites stacked before a previous launch. Credit: SpaceX

At lower altitudes, the Starlink satellites will fly in a region with busier space traffic. SpaceX says its Starlink spacecraft can maneuver to avoid collisions with other objects in orbit, and it releases orbital data on the Starlink satellites so other operators can also perform evasive maneuvers.

Astronomers have also raised concerns about the brightness of the Starlink satellites, which could interfere with ground-based telescope images, particularly around sunrise and sunset.

The Starlink satellites reflect more sunlight than SpaceX or astronomers anticipated before the first dedicated Starlink launch last year. The American Astronomical Society and other groups are working with SpaceX to try and limit the satellites’ impacts on astronomy.

“SpaceX is committed to promoting all forms of space exploration, which is why it has already taken a number of proactive steps to ensure it does not materially impact optical astronomy,” the company wrote in Friday’s application to the FCC, which does not have regulatory authority over the brightness of satellites. “SpaceX is working with U.S. and international astronomy organizations and observatories to measure scientifically the actual impact of its satellites.”

Flying more Starlink satellites at lower altitudes could make the relay nodes appear brighter from the ground, but there will be fewer Starlink satellites visible in the sky at one time. The spacecraft at lower altitudes will also spend less time illuminated by sunlight.

One of 60 Starlink satellites launched Jan. 6 carried a new darker coating intended to reduce the spacecraft’s reflectivity. SpaceX said last month that preliminary data indicated a “notable reduction” in the brightness of that satellite, which has been dubbed “DarkSat.”

Beyond this (darkening) treatment, SpaceX is developing new mitigation efforts that it plans to test in the coming months,” SpaceX wrote in Friday’s FCC filing. “Additionally, SpaceX will make satellite tracking data available so astronomers can better coordinate their observations with our satellites.”

One change SpaceX is studying is the addition of a sunshade, or visor, to unfurl like an umbrella on Starlink satellites to reduce the amount of sunlight glinting off the spacecraft.

Beyond the 4,400 Ku-band and Ka-band satellites covered in Friday’s application for a modified FCC license, SpaceX plans to launch another 7,500 V-band data relay stations into orbits around 214 miles (345.6 kilometers) in altitude. The FCC has already approved SpaceX to operate the V-band network.

SpaceX’s next Starlink launch after Wednesday could happen as soon as early-to-mid May on another Falcon 9 rocket mission from Cape Canaveral.

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Follow Stephen Clark on Twitter: @StephenClark1.

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2 astronauts head for launch pad for historic SpaceX flight – Yahoo Canada Finance

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2 astronauts climb aboard SpaceX rocket for historic flight

CAPE CANAVERAL, Fla. — Two NASA astronauts climbed into their capsule Saturday for a second attempt at a history-making ride into orbit aboard a rocket ship designed and built by Elon Musk’s SpaceX company.

Stormy weather had threatened another postponement most of the day, but the outlook improved markedly in the afternoon, just ahead of the scheduled 3:22 p.m. liftoff of the 260-foot Falcon 9 in what would be the first launch of astronauts into orbit by a private company.

Their destination: the International Space Station, 250 miles above Earth.

It would also be NASA’s first human spaceflight launched from U.S. soil in nearly a decade.

The mission unfolded amid the gloom of the coronavirus outbreak, which has killed over 100,000 Americans, and racial unrest across the U.S. over the death of George Floyd, a handcuffed black man, at the hands of Minneapolis police. NASA officials and others held out hope the flight would would lift American spirits.

“Maybe there’s an opportunity here for America to maybe pause and look up and see a bright, shining moment of hope at what the future looks like, that the United States of America can do extraordinary things even in difficult times,” NASA Administrator Jim Bridenstine said.

Veteran astronauts Doug Hurley and Bob Behnken pulled on their angular, white-and-black spacesuits with help from technicians wearing masks, gloves and black hoods that made them look like ninjas.

Before setting out for the launch pad in a gull-wing Tesla SUV — another Musk product — Behnken pantomimed a hug of his 6-year-old son, Theo, and said: “Are you going to listen to Mommy and make her life easy?” Hurley blew kisses to his 10-year-old son and wife.

Wednesday’s countdown of the rocket and its bullet-shaped Dragon capsule was halted at just under 17 minutes because of the threat of lightning.

President Donald Trump and Vice-President Mike Pence returned to the Kennedy Space Center for the second launch attempt.

Ever since the space shuttle was retired in 2011, NASA has relied on Russian spaceships launched from Kazakhstan to take U.S. astronauts to and from the space station.

“I would be lying to you if I told you I wasn’t nervous,” Bridenstine said before the launch attempt. “We want to do everything we can to minimize the risk, minimize the uncertainty, so that Bob and Doug will be safe.”

Because of the coronavirus, NASA severely limited the number of employees, visitors and journalists allowed deep inside Kennedy Space Center, and the crowd was relatively small, at a few thousand. At the centre ‘s tourist complex, though, all 4,000 tickets were snapped up in a few hours.

The space agency urged people to stay safe and watch from home, and by NASA’s count, at least 1.14 million viewers followed the launch preparation online. But spectators also began lining the Cape Canaveral area’s beaches and roads. Signs along the main beach drag read, “Godspeed.”

Among the spectators was Neil Wight, a machinist from Buffalo, New York, who staked out a view of the launch pad from a park in Titusville.

“It’s pretty historically significant in my book and a lot of other people’s books. With everything that’s going on in this country right now, it’s important that we do things extraordinary in life,” Wight said. “We’ve been bombarded with doom and gloom for the last six, eight weeks, whatever it is, and this is awesome. It brings a lot of people together.”

NASA hired SpaceX and Boeing in 2014 to taxi astronauts to and from the space station, under contracts totalling $7 billion. Both companies launched their crew capsules last year with test dummies. SpaceX’s Dragon aced all of its objectives, while Boeing’s Starliner capsule ended up in the wrong orbit and was almost destroyed because of software errors.

As a result, the first Starliner flight carrying astronauts isn’t expected until next year.

___

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

Marcia Dunn, The Associated Press

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Two astronauts climb aboard SpaceX rocket for historic flight – CTV News

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CAPE CANAVERAL, FLA. —
Despite more storms in the forecast, two NASA astronauts climbed into their capsule Saturday for a second attempt at a history-making ride into orbit aboard a rocket ship designed and built by Elon Musk’s SpaceX company.

With the flight already delayed three days by bad weather, forecasters put the odds of acceptable conditions at 50-50 for the 3:22 p.m. liftoff of the 270-foot Falcon 9 in what would be the first launch of astronauts into orbit by a private company.

Their destination: the International Space Station, 250 miles above Earth.

It would also be NASA’s first human spaceflight launched from U.S. soil in nearly a decade.

NASA officials and others held out hope the mission would be a morale-booster amid the gloom of the coronavirus outbreak, which has killed over 360,000 people worldwide, including more than 100,000 Americans.

Veteran astronauts Doug Hurley and Bob Behnken pulled on their angular, white-and-black spacesuits with help from technicians wearing masks, gloves and black hoods that made them look like ninjas.

Before setting out for the launch pad in a gull-wing Tesla SUV — another Musk product — Behnken pantomimed a hug of his 6-year-old son, Theo, and said: “Are you going to listen to Mommy and make her life easy?” Hurley blew kisses to his 10-year-old son and wife.

SpaceX and NASA monitored the weather not just at Kennedy Space Center, where rain, thick clouds and the chance of lightning threatened another postponement, but all the way up the Eastern Seaboard and across the North Atlantic to Ireland. Waves and wind need to be within certain limits in case the astronauts have to make an emergency splashdown on the way to orbit.

Wednesday’s countdown of the rocket and its bullet-shaped Dragon capsule was halted at just under 17 minutes because of the threat of lightning.

Ever since the space shuttle was retired in 2011, NASA has relied on Russian spaceships launched from Kazakhstan to take U.S. astronauts to and from the space station.

“I would be lying to you if I told you I wasn’t nervous,” NASA Administrator Jim Bridenstine said before the launch attempt. “We want to do everything we can to minimize the risk, minimize the uncertainty, so that Bob and Doug will be safe.”

President Donald Trump and Vice-President Mike Pence planned to return for the second launch attempt.

Because of the coronavirus, NASA severely limited the number of employees, visitors and journalists allowed deep inside Kennedy Space Center, and the crowd was relatively small, at a few thousand. At the centre’s tourist complex, though, all 4,000 tickets were snapped up in a few hours.

The space agency urged people to stay safe and watch from home, and by NASA’s count, at least 1.14 million viewers followed the launch preparation online. But spectators also began lining the Cape Canaveral area’s beaches and roads. Signs along the main beach drag read, “Godspeed.”

Among the spectators was Neil Wight, a machinist from Buffalo, New York, who staked out a view of the launch pad from a park in Titusville.

“It’s pretty historically significant in my book, and a lot of other people’s books. With everything that’s going on in this country right now, it’s important that we do things extraordinary in life,” Wight said. “We’ve been bombarded with doom and gloom for the last six, eight weeks, whatever it is, and this is awesome. It brings a lot of people together.”

NASA hired SpaceX and Boeing in 2014 to taxi astronauts to and from the space station, under contracts totalling $7 billion. Both companies launched their crew capsules last year with test dummies. SpaceX’s Dragon aced all of its objectives, while Boeing’s Starliner capsule ended up in the wrong orbit and was almost destroyed because of software errors.

As a result, the first Starliner flight carrying astronauts isn’t expected until next year.

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How to Make the Food and Water Mars-Bound Astronauts Will Need for Their Mission – Universe Today

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If we ever intend to send crewed missions to deep-space locations, then we need to come up with solutions for how to keep the crews supplied. For astronauts aboard the International Space Station (ISS), who regularly receive resupply missions from Earth, this is not an issue. But for missions traveling to destinations like Mars and beyond, self-sufficiency is the name of the game!

This is the idea behind projects like BIOWYSE and TIME SCALE, which are being developed by the Centre for Interdisciplinary Research in Space (CIRiS) in Norway. These two systems are all about providing astronauts with a sustainable and renewable supply of drinking water and plant food. In so doing, they address two of the most important needs of humans performing long-duration missions that will take them far from home.

Even though the ISS can be resupplied in as little as six hours (the time between launch and the time a supply capsule will dock with the station), astronauts still rely on conservation measures while in orbit. In fact, roughly 80% of the water aboard the ISS comes from airborne water vapor (generated by breathing and sweat) as well as recycled shower water and urine – all of which is treated with chemicals to make it safe for drinking.

Food is another matter. NASA estimates that every astronaut aboard the ISS will consume 0.83 kg (1.83 pounds lbs) of food per meal, which works out to about 2.5 kg (5.5 lbs) a day. About 0.12 kg (0.27 pounds) of every meal is just from the packaging material, which means a single astronaut will generate close to a pound of waste per day – and that’s not even including the other kind of “waste” that comes from eating!

In short, the ISS relies on costly resupply missions to provide 20% of its water and all of its food. But if and when astronauts establish outposts on the Moon and Mars, this may not be an option. While sending supplies to the Moon can be done in three days, the need to do so regularly will make the cost of sending food and water prohibitive. Meanwhile, it takes eight months for spacecraft to reach Mars, which is totally impractical.

It is little wonder then why the proposed mission architectures to the Moon and Mars include in-situ resource utilization (ISRU), where astronauts will use local resources to be as self-sufficient as possible. The availability of ice on the lunar and Martian surfaces is a prime example, which will be harvested to provide drinking and irrigation water. But missions to deep-space locations will not have this option while they are in transit.

To provide a sustainable supply of water, Dr. Emmanouil Detsis and colleagues are developing the Biocontamination Integrated cOntrol of Wet Systems for Space Exploration (BIOWYSE). This project began as an investigation for ways to store freshwater for extended periods of time, monitor it in real-time for signs of contamination, decontaminate it with UV light (rather than chemicals), and dispense it as needed.

https://horizon-media.s3-eu-west-1.amazonaws.com/s3fs-public/field/image/time_scale_crop.jpg
The prototype space greenhouse developed by the TIME SCALE project, which recycles nutrients to grow food. Credit: Karoliussen/HORIZON

What resulted was an automated machine that could perform all of these tasks. As Dr. Detsis explained:

“We wanted a system where you take it from A to Z, from storing the water to making it available for someone to drink. That means you store the water, you are able to monitor the biocontamination, you are able to disinfect if you have to, and finally you deliver to the cup for drinking… When someone wants to drink water you press the button. It’s like a water cooler.”

In addition to monitoring stored water, the BIOWYSE machine is also capable of analyzing wet surfaces inside a spacecraft for signs of contamination. This is important since closed-systems like spacecraft and space stations, you have humidity buildup, which can cause water to accumulate in areas that are unclean. Once this water is reclaimed, it then becomes necessary to decontaminate all the water stored in the system.

“The system is designed with future habitats in mind,” added Dr. Detsis. “So a space station around the moon, or a field laboratory on Mars in decades to come. These are places where the water may have been sitting there some time before the crew arrives.”

http://www.esa.int/var/esa/storage/images/esa_multimedia/images/2001/07/biolab_is_designed_to_support_biological_experiments/9159967-5-eng-GB/Biolab_is_designed_to_support_biological_experiments_pillars.jpg
Artist’s impression of Biolab. a facility designed to support biological experiments on micro-organisms, small plants and small invertebrates. Credit: ESA – D. Ducros

The Technology and Innovation for Development of Modular Equipment in Scalable Advanced Life Support Systems for Space Exploration (TIME SCALE) project, meanwhile, is designed to recycle water and nutrients for the sake of growing plants. This project is overseen by Dr. Ann-Iren Kittang Jost from the Centre for Interdisciplinary Research in Space (CIRiS) in Norway.

This system is not unlike the European Modular Cultivation System (EMCS) or the Biolab system, which were sent to the ISS in 2006 and 2018 (respectively) to conduct biological experiments in space. Drawing inspiration from these systems, Dr. Jost and her colleagues designed a “greenhouse in space” that could cultivate plants and monitor their health. As she put it:

“We (need) state of the art technologies to cultivate food for future space exploration to the moon and Mars. We took (the ECMS) as a starting point to define concepts and technologies to learn more about cultivating crops and plants in microgravity.”

Much like its predecessors, Biolab and the ECMS, the TIME SCALE prototype relies on a spinning centrifuge to simulate lunar and Martian gravity and measures the effect this has on plants’ uptake of nutrients and water. This system could also be useful here on Earth, allowing greenhouses to reuse nutrients and water and more advanced sensor technology to monitor plant health and growth.

Plants cultivated in the TPU autonomous greenhouse. Credit: TPU

Technologies like these will be crucial when it comes time to establish a human presence on the Moon, on Mars, and for the sake of deep-space missions. In the coming years, NASA plans to make the long-awaited return to the Moon with Project Artemis, which will be the first step in the creation of what they envision as a program for “sustainable lunar exploration.”

Much of that vision rests on the creation of an orbital habitat (the Lunar Gateway) as well as the infrastructure on the surface (the Artemis Base Camp) needed to support an enduring human presence. Similarly, when NASA begins making crewed missions to Mars, the mission architecture calls for an orbital habitat (the Mars Base Camp), likely followed by one on the surface.

In all cases, the outposts will need to be relatively self-sufficient since resupply missions won’t be able to reach them in a matter of hours. As Dr. Detsis explained:

“It will not be like the ISS. You are not going to have a constant crew all the time. There will be a period where the laboratory might be empty, and will not have crew until the next shift arrives in three or four months (or longer). Water and other resources will be sitting there, and it may build up microorganisms.”

By having technologies that can ensure that drinking water is safe, clean, and in steady supply – and that plants can be grown in a sustainable way – outposts and deep-space missions will be able to achieve a level of self-sufficiency and be less reliant on Earth.

Further Reading: HORIZON/European Commission

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