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SpaceX to attempt historic back-to-back Falcon 9 flights – CBS News

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SpaceX is gearing up for back-to-back launches on Sunday just nine hours apart, the shortest span between two Florida orbit-class flights since 1966. The launches are a dramatic bid to put 60 more Starlink internet relay stations into orbit followed by an Argentine remote sensing satellite.

The planned launchings follow on the heels of a last-second “hot-fire abort” of a United Launch Alliance Delta 4 Heavy rocket at the Cape Canaveral Air Force Station early Saturday that grounded a classified National Reconnaissance Office spy satellite.

At least one of the heavy-lift Delta 4’s three first stage engines was in the process of igniting when computers commanded a shutdown just three seconds before the planned liftoff. It’s not clear what triggered the abort, but the flight will be delayed at least a week pending inspections and corrective action.

Fire erupts from the base of a United Launch Alliance Delta 4 Heavy rocket as the engine start sequence began and then shut down in a “hot-fire abort,” grounding the booster for at least a week.

ULA webcast


SpaceX already had clearance from the Federal Aviation Administration and the Air Force Eastern Range to attempt back-to-back launches Sunday.

But the weather could play a role in the historic double header, with forecasters calling for a 50-50 chance of acceptable weather for the morning Starlink launch, declining to 40 percent “go” for the evening launch of Argentina’s SAOCOM 1B satellite.

If the weather cooperates, the Starlink flight will take off from pad 39A at the Kennedy Space Center at 10:12 a.m. ET. It will mark SpaceX’s 100th flight since the company’s first launch of a Falcon 1 in 2006 and the 94th flight of its workhorse Falcon 9. Three triple-core Falcon Heavies also have been launched.

The 60 Starlinks set for launch Sunday will boost SpaceX’s constellation to 713. The rocket’s first stage, making its second flight, will attempt to land on an off-shore droneship after boosting the vehicle out of the lower atmosphere.

Nine hours and six minutes after the Sunday morning launch, another Falcon 9 is scheduled for takeoff from pad 40 at the nearby Cape Canaveral Air Force Station to put SAOCOM 1B into an orbit around Earth’s poles, the first such flight from Florida since 1969.

The Falcon 9’s first stage, making its fourth flight, will attempt a landing back at the Cape Canaveral Air Force Station. If the Starlink and SAOCOM landings are successful, SpaceX’s record will stand at 60 first stage recoveries, 18 at the Air Force station, 40 on droneships and two at Vandenberg Air Force Base in California.

To reach a polar orbit from Cape Canaveral, the Falcon 9 will take off on a southerly trajectory and then carry out a “dogleg” maneuver once clear of Florida’s coast to bend the trajectory more directly south. The flight path will carry the rocket over Cuba.

082920-f9-file.jpg
A Falcon 9 rocket takes off from pad 40 at the Cape Canaveral Air Force Station on the most recent Starlink mission last August. Another Starlink flight is planned for Sunday, along with launch of an Argentine remote-sensing satellite.

SpaceX


In 1960, falling debris from a malfunctioning rocket reportedly killed a cow in Cuba, prompting protests in the island nation. All polar orbit missions since 1969 have taken off from Vandenberg where rockets remain above the Pacific Ocean all the way to orbit.

SpaceX initially planned to launch SAOCOM 1B from Vandenberg, but sought permission to move the flight to Cape Canaveral to ease ground processing issues.

The company presumably won government approval for the move in part because of the dogleg maneuver, which minimizes overflight of populated areas, the rocket’s high altitude by the time it reaches populated areas farther downrange and because the Falcon 9 features an automated flight safety system. The AFTS is designed to quickly terminate a flight if an impending catastrophic problem is detected.

The 6,720-pound SAOCOM 1B requires a polar orbit to enable its cloud-penetrating radar to observe the entire planet as it rotates below. The spacecraft will work in concert with an identical L-band radar mapper launched in 2018 along with Italy’s COSMO-SkyMed X-band satellites.

Bound for a 360-mile-high orbit, the $600 million SOACOM system is designed to monitor soil moisture and a range of other factors affecting the agricultural sector, collecting high-resolution data around the clock regardless of cloud cover.

“One of the main targets of the SAOCOM satellites is to provide information for the agriculture sector,” Raúl Kulichevsky, executive and technical director of CONAE, Argentina’s space agency, told Spaceflight Now.

“One of the things we develop is soil moisture maps, not only of the surface, but taking advantage of the L-band capabilities we can measure the soil moisture 1 meter below the surface of the land. So this is very important information.”

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2020 could be on track to be another record-setting warm year, despite global lockdowns – CBC.ca

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People around the world participated in the Global Day of Climate Action on Friday, a reminder that even though we’re in the midst of one of the biggest health issues to face humanity, climate change stands to pose an even bigger threat — with increased chances of drought, wildfires, hurricanes, flooding and heat waves.

At the start of the COVID-19 pandemic earlier this year, businesses shuttered and people went into lockdown. As a result, greenhouse gas emissions dropped, including both nitrogen dioxide and carbon dioxide (CO2), two drivers of global warming.

There was some hope that this could be the silver lining to a tragic situation, but the fact is, it’s unlikely to make a dent in the upward trend of Earth’s rising temperatures.

In fact, the U.S. National Atmospheric and Oceanic Administration’s National Centers for Environmental Information (NCEI) recorded that globally, August’s land and sea temperatures were the second-highest on record. For North America, it was the hottest August on record, at 1.52 C above average. August also marked the 428th-consecutive month with temperatures above the 20th-century average.

The issue is that CO2 has already accumulated in our atmosphere, and Earth is playing a game of catch-up.

“Carbon dioxide can last thousands and thousands of years in the atmosphere,” said Ahira Sanchez-Lugo, a physical scientist who compiles global temperature data at NCEI. “So just because with the pandemic we’ve seen a reduction in emissions, that doesn’t mean that we will see a reduction in global temperatures any time soon.”

This graph illustrates the rise of cumulative CO2 in the atmosphere over time. The data before 1958 was taken using ice cores. (Scripps Institution of Oceanography)

Climatologist Michael Mann, a professor of atmospheric science at Penn State University, said there’s likely to be a drop in emissions but that it won’t make a large difference. 

“It will probably lead to a roughly four to five per cent reduction in carbon emissions for 2020. That means a very slightly lower rate of warming,” he said. 

Too many blankets

Sanchez-Lugo likes to use the analogy of CO2 acting as Earth’s blanket: It’s needed in order to regulate the planet’s temperature, but additional accumulation is like throwing more and more blankets on top. 

“So that’s what’s happening right now in that sense: Right now, Earth already has several layers of blankets, and just because we stopped or we’ve reduced carbon greenhouse emissions recently, that doesn’t mean that we’re peeling off those blankets,” she said. 

Year-to-date, the temperature is 1.03 C higher than the average and is only behind 2016’s record warmth of 1.08 C above average. 

The hottest year on record was 2016, reaching 0.94 C above the average. It also marked the third-consecutive year a record was set. But that was also the year of a moderate to strong El Nino, a natural phenomenon that is characterized by warming in the Pacific Ocean — which in turn causes higher temperatures in some regions and greater precipitation in others. 

This year, however, has not been a year of El Nino.

So does this mean we might break the 2016 record without its warming effect?

“Right now, there is about a 55 per cent chance of [2020] being the second warmest,” Sanchez-Lugo said, “and … about a 39 per cent chance of it being the warmest year on record.”

While 2020 may not be on top of the list, it’s likely that more and more records will be set in the coming years.

This graphic illustrates temperature anomalies across the globe during August 2020. (NOAA/NCEI)

A study published in May in the Bulletin of the American Meteorological Society, of which Sanchez-Lugo was a co-author suggested that “there’s a greater than a 99 per cent chance that most of the next 10 years through 2028 will be ranked among the top 10 warmest.”

The pandemic might be a way of illustrating that countries can reduce their emissions by altering their lifestyles, such as by not commuting to work five days a week, which would be one way to continue to see emissions decrease.

But Mann said big changes need to be made in order to see significant improvement in the decades to come.

“If we can reduce carbon emissions a bit more — about seven per cent a year — for each of the next 10 years, we can stay on a path that stabilizes global warming below 1.5 C, preventing the most damaging and dangerous impacts of climate change,” he said.

“However, simple behavioural changes won’t get us there. We need systematic change, i.e. policies to rapidly decarbonize our economy.”

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New measurements show moon has hazardous radiation levels – FOX 8 Live WVUE

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Wimmer-Schweingruber said the radiation levels are close to what models had predicted. The levels measured by Chang’e 4, in fact, “agree nearly exactly” with measurements by a detector on a NASA orbiter that has been circling the moon for more than a decade, said Kerry Lee, a space radiation expert at Johnson Space Center in Houston.

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China's Chang'e-4 detects hazardous radiation levels on the Moon – CGTN

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Space radiation on the moon is two to three times higher than that on the International Space Station (ISS). This could be one of the biggest dangers for future moon explorers, the Chinese moon probe discovered.  

A Chinese-German team reported on the radiation data collected by the moon lander – named Chang’e-4 for the Chinese moon goddess – in the U.S. journal Science Advances. Chang’e-4 made the first ever soft-landing on the far side of the Moon in January, 2019.  

Read more:  China’s Chang’e-4 lunar probe completes 22nd lunar day with latest findings

The discovery provides the first full measurements of radiation exposure from the lunar surface, vital information for NASA and others aiming to send astronauts to the moon, the study noted. 

“This is an immense achievement in the sense that now we have a data set which we can use to benchmark our radiation” and better understand the potential risk to people on the moon, said Thomas Berger, a physicist with the German Space Agency’s medicine institute. 

Though Apollo missions in the 1960s and 1970s proved it was safe for people to spend a few days on the lunar surface, NASA did not take daily radiation measurements that would help scientists quantify just how long crews could stay. 

The question is now answered.  

Astronauts would get 200 to 1,000 times more radiation on the moon than what we experience on Earth – or five to 10 times more than passengers on a trans-Atlantic airline flight, noted Robert Wimmer-Schweingruber of Christian-Albrechts University in Kiel, Germany. 

“The radiation levels we measured on the Moon are about 200 times higher than on the surface of the Earth and five to 10 times higher than on a flight from New York to Frankfurt,” added Wimmer-Schweingruber. 

That means humans can stay at most two months on the surface of the Moon without special protection measures, according to Robert Wimmer-Schweingruber, an astrophysicist at the University of Kiel. 

Sources of radiation

There are several sources of radiation exposure: galactic cosmic rays, sporadic solar particle events (for example from solar flares), and neutrons and gamma rays from interactions between space radiation and the lunar soil. 

Radiation is measured using the unit sievert, which quantifies the amount absorbed by human tissues. 

The team found that the radiation exposure on the Moon is 1,369 microsieverts per day – about 2.6 times higher than the International Space Station crew’s daily dose. 

The reason for this is that the ISS is still partly shielded by the Earth’s protective magnetic bubble, called the magnetosphere, which deflects most radiation from space. 

Earth’s atmosphere provides additional protection for humans on the surface, but we are more exposed the higher up we go.

NASA is planning to bring humans to the Moon by 2024 under the Artemis mission and has said it has plans for a long term presence that would include astronauts working and living on the surface. 

For Wimmer-Schweingruber there is one work-around if we want humans to spend more than two or three months: build habitats that are shielded from radiation by coating them with 80 centimeters (30 inches) of lunar soil. 

(With input from agencies)

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