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SpaceX just did something it’s never done before – BGR

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  • SpaceX successfully launched a South Korean military satellite into orbit on Monday.
  • The mission was historic as it was the first time SpaceX has successfully recovered both halves of its nosecone after launch.
  • By snagging the nosecone halves as they fall, the company could save millions of dollars and further shorten the turnaround time between launches.

SpaceX has built a business around its reusable rocket technology. The company saves money and performs more frequent launches thanks to its ability to use boosters multiple times. It’s gotten very, very good at recovering its boosters, but capturing other rocket components has proven more challenging.

In yesterday’s mission to send a South Korean military satellite skyward, the company pulled off something it’s never done before by snagging both halves of its rocket’s nosecone. The two halves — called fairings — are pricey pieces of equipment in their own right, and if SpaceX can make a habit of recovering them, it’ll make subsequent launches that much easier.

The mission itself, which delivered South Korea’s ANASIS-II satellite into orbit, had been previously delayed. It was one of several SpaceX missions that had to be pushed back for a variety of reasons, but the company managed to pull off the launch yesterday and, as an added bonus, made a bit of history for itself along the way.

Recovering rocket boosters is challenging, and SpaceX had many failures along its path to perfecting its technique. Today, the company’s boosters almost always land right where they’re supposed to, and SpaceX can rapidly refurbish them for subsequent trips to space. Catching the nosecone halves is quite a bit more challenging.

The nosecone of the Falcon 9 splits in half to deliver its payloads. Those halves then tumble back down to Earth, and SpaceX has ships with massive nets that do their best to catch them as they fall. However, even with parachutes equipped, the odd shape of the components adds some unpredictability to their descent. Catching them isn’t easy, and SpaceX is usually lucky if it manages to catch just one of the halves.

In a tweet shortly after the Monday launch, SpaceX boss Elon Musk revealed that both halves of the nosecone were recovered by the company’s vessels.

In speaking about the recovery of the company’s nosecones, Musk has thrown out some lofty figures as to their value. Allowing the nosecones to splashdown in the ocean is bad news, as salty seawater can damage sensitive components. He’s claimed that by recovering the nosecones, the company could save millions of dollars.

Along with the nosecones, SpaceX also recovered its Falcon 9 booster, which is basically a given at this point. The company tweeted out a video of the rocket stage landing on a droneship. It’s the 57th time the company has successfully recovered its pricey rocket booster.

Mike Wehner has reported on technology and video games for the past decade, covering breaking news and trends in VR, wearables, smartphones, and future tech.

Most recently, Mike served as Tech Editor at The Daily Dot, and has been featured in USA Today, Time.com, and countless other web and print outlets. His love of
reporting is second only to his gaming addiction.

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Lake Huron sinkhole surprise: The rise of oxygen on early Earth linked to changing planetary rotation rate – Phys.org

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A scuba diver observes the purple, white and green microbes covering rocks in Lake Huron’s Middle Island Sinkhole. Credit: Phil Hartmeyer, NOAA Thunder Bay National Marine Sanctuary.

The rise of oxygen levels early in Earth’s history paved the way for the spectacular diversity of animal life. But for decades, scientists have struggled to explain the factors that controlled this gradual and stepwise process, which unfolded over nearly 2 billion years.

Now an international research team is proposing that increasing on the early Earth—the spinning of the young planet gradually slowed over time, making the days longer—may have boosted the amount of oxygen released by photosynthetic cyanobacteria, thereby shaping the timing of Earth’s oxygenation.

Their conclusion was inspired by a study of present-day microbial communities growing under extreme conditions at the bottom of a submerged Lake Huron sinkhole, 80 feet below the water’s surface. The water in the Middle Island Sinkhole is rich in sulfur and low in oxygen, and the brightly colored bacteria that thrive there are considered good analogs for the single-celled organisms that formed mat-like colonies billions of years ago, carpeting both land and seafloor surfaces.

The researchers show that longer day length increases the amount of oxygen released by photosynthetic microbial mats. That finding, in turn, points to a previously unconsidered link between Earth’s oxygenation history and its . While the Earth now spins on its axis once every 24 hours, day length was possibly as brief as 6 hours during the planet’s infancy.

The team’s findings are scheduled for publication Aug. 2 in the journal Nature Geoscience.

Lead authors are Judith Klatt of the Max Planck Institute for Marine Microbiology and Arjun Chennu of the Leibniz Centre for Tropical Marine Research. Klatt is a former postdoctoral researcher in the lab of University of Michigan geomicrobiologist Gregory Dick, who is one of the study’s two corresponding authors. The other co-authors are from U-M and Grand Valley State University.

“An enduring question in the Earth sciences has been how did Earth’s atmosphere get its oxygen, and what factors controlled when this oxygenation took place,” Dick said from the deck of the R/V Storm, a 50-foot NOAA research vessel that carried a team of scientists and scuba divers on a sample-collection trip from the town of Alpena, Michigan, to the Middle Island Sinkhole, several miles offshore.

“Our research suggests that the rate at which the Earth is spinning—in other words, its day length—may have had an important effect on the pattern and timing of Earth’s oxygenation,” said Dick, a professor in the U-M Department of Earth and Environmental Sciences.

The researchers simulated the gradual slowing of Earth’s rotation rate and showed that longer days would have boosted the amount of oxygen released by early cyanobacterial mats in a manner that helps explain the planet’s two great oxygenation events.

[embedded content]

The project began when co-author Brian Arbic, a physical oceanographer in the U-M Department of Earth and Environmental Sciences, heard a public lecture about Klatt’s work and noted that day length changes could play a role, over geological time, in the photosynthesis story that Dick’s lab was developing.

Cyanobacteria get a bad rap these days because they are the main culprits behind the unsightly and toxic algal blooms that plague Lake Erie and other water bodies around the world.

But these microbes, formerly known as blue-green algae, have been around for billions of years and were the first organisms to figure out how to capture energy from sunlight and use it to produce organic compounds through photosynthesis—releasing oxygen as a byproduct.

Masses of these simple organisms living in primeval seas are credited with releasing oxygen that later allowed for the emergence of multicellular animals. The planet was slowly transformed from one with vanishingly small amounts of oxygen to present-day atmospheric levels of around 21%.

At the Middle Island Sinkhole in Lake Huron, purple oxygen-producing cyanobacteria compete with white sulfur-oxidizing bacteria that use sulfur, not sunlight, as their main energy source.

In a microbial dance repeated daily at the bottom of the Middle Island Sinkhole, filmy sheets of purple and white microbes jockey for position as the day progresses and as environmental conditions slowly shift. The white sulfur-eating bacteria physically cover the purple cyanobacteria in the morning and evening, blocking their access to sunlight and preventing them from carrying out oxygen-producing photosynthesis.

But when sunlight levels increase to a critical threshold, the sulfur-oxidizing bacteria migrate back down below the photosynthetic cyanobacteria, enabling them to start producing oxygen.

New theory: Earth's longer days kick-started oxygen growth
This June 19, 2019 photo provided by NOAA Thunder Bay National Marine Sanctuary shows purple microbial mats in the Middle Island Sinkhole in Lake Huron, Mich. Small hills and “fingers” like this one in the mats are caused by gases like methane and hydrogen sulfide bubbling up beneath them. Feel like days are just getting longer? They are and it’s a good thing because we wouldn’t have much to breathe if they weren’t, according to a new explanation for how Earth’s oxygen rich atmosphere may have developed because of Earth’s rotation slowing. Scientists provided evidence for this new hypothesis by lab testing gooey smelly purple bacteria from a deep sinkhole in Lake Huron. Credit: Phil Hartmeyer/NOAA Thunder Bay National Marine Sanctuary

The vertical migration of sulfur-oxidizing bacteria has been observed before. What’s new is that the authors of the Nature Geoscience study are the first to link these microbial movements, and the resultant rates of oxygen production, to changing day length throughout Earth’s history.

“Two groups of microbes in the Middle Island Sinkhole mats compete for the uppermost position, with sulfur-oxidizing bacteria sometimes shading the photosynthetically active cyanobacteria,” Klatt said while processing a core sample from Middle Island Sinkhole microbial mats in an Alpena laboratory. “It’s possible that a similar type of competition between microbes contributed to the delay in oxygen production on the early Earth.”

A key to understanding the proposed link between changing day length and Earth’s oxygenation is that longer days extend the afternoon high-light period, allowing photosynthetic cyanobacteria to crank out more oxygen.

“The idea is that with a shorter day length and shorter window for high-light conditions in the afternoon, those white sulfur-eating bacteria would be on top of the photosynthetic bacteria for larger portions of the day, limiting oxygen production,” Dick said as the boat rocked on choppy waters, moored a couple hundred yards from Middle Island.

The present-day Lake Huron microbes are believed to be good analogs for ancient organisms in part because the extreme environment at the bottom of the Middle Island Sinkhole likely resembles the harsh conditions that prevailed in the shallow seas of early Earth.

Lake Huron is underlain by 400-million-year-old limestone, dolomite and gypsum bedrock that formed from the saltwater seas that once covered the continent. Over time, the movement of groundwater dissolved some of that bedrock, forming caves and cracks that later collapsed to create both on-land and submerged sinkholes near Alpena.

Cold, oxygen-poor, sulfur-rich groundwater seeps into the bottom of the 300-foot-diameter Middle Island Sinkhole today, driving away most plants and animals but creating an ideal home for certain specialized microbes.

Dick’s team, in collaboration with co-author Bopaiah Biddanda of the Annis Water Resources Institute at Grand Valley State University, has been studying the microbial mats on the floor of Middle Island Sinkhole for several years, using a variety of techniques. With the help of scuba divers from NOAA’s Thunder Bay National Marine Sanctuary—which is best known for its shipwrecks but is also home to the Middle Island Sinkhole and several others like it—the researchers deployed instruments to the lake floor to study the chemistry and biology there.

They also brought mat samples to the lab to conduct experiments under controlled conditions.

Klatt hypothesized that the link between day length and oxygen release can be generalized to any given mat ecosystem, based on the physics of oxygen transport. She teamed up with Chennu to conduct detailed modeling studies to relate microbial mat processes to Earth-scale patterns over geological timescales.

The modeling studies revealed that day length does, in fact, shape oxygen release from the mats.

“Simply speaking, there is just less time for the oxygen to leave the mat in shorter days,” Klatt said.

This led the researchers to posit a possible link between longer day lengths and increasing atmospheric oxygen levels. The models show that this proposed mechanism might help explain the distinctive stepwise pattern of Earth’s oxygenation, as well as the persistence of low-oxygen periods through most of the planet’s history.

Throughout most of Earth’s history, atmospheric oxygen was only sparsely available and is believed to have increased in two broad steps. The Great Oxidation Event occurred about 2.4 billion years ago and has generally been credited to the earliest photosynthesizing cyanobacteria. Nearly 2 billion years later a second surge in , known as the Neoproterozoic Oxygenation Event, occurred.

Earth’s rotation rate has been slowly decreasing since the planet formed about 4.6 billion years ago due to the relentless tug of the moon’s gravity, which creates tidal friction.


Explore further

Researchers find oxygen spike coincided with ancient global extinction


More information:
Possible link between Earth’s rotation rate and oxygenation, Nature Geoscience (2021). DOI: 10.1038/s41561-021-00784-3 , www.nature.com/articles/s41561-021-00784-3

Citation:
Lake Huron sinkhole surprise: The rise of oxygen on early Earth linked to changing planetary rotation rate (2021, August 2)
retrieved 2 August 2021
from https://phys.org/news/2021-08-lake-huron-sinkhole-oxygen-early.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.

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Astronomers spot light behind a black hole for the first time, reaffirming Einstein's theory of general relativity – TechSpot

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Something to look forward to: An international team of astronomers have observed light from behind a black hole for the first time. Future observatories, like the Advanced Telescope for High Energy Astrophysics (Athena) should provider even higher resolution images with much shorter observation times.1

Led by Stanford University’s Dan Wilkins, the team focused on a black hole that is 10 million times as massive as our sun and located 1,800 million light years away in a galaxy called I Zwicky.

Armed with the European Space Agency’s XMM-Newton and NASA’s NuSTAR space telescopes, the astronomers observed bright flares of X-ray light coming from around the black hole. The X-ray flares echoed off of gas that was falling into the black hole, and as the flares were subsiding, the telescopes were remarkably able to pick up smaller flashes of X-rays that were different “colors.” These were the echoes bouncing off the gas behind the black hole.

“Any light that goes into that black hole doesn’t come out, so we shouldn’t be able to see anything that’s behind the black hole,” Wilkins said. “The reason we can see that is because that black hole is warping space, bending light and twisting magnetic fields around itself,” he added.

The black hole’s gravitational pull is responsible for the warping of space.

This is the first time that astronomers have directly observed light from behind a black hole, and it also matches Einstein’s theory of general relativity, yet again confirming his predictions.

The team’s findings were recently published in the scientific journal Nature.

Image credit Dan Wilkins

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Russian cosmonauts give video tour of module that jolted space station – Euronews

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MOSCOW – Russian cosmonauts have given a video tour of the interior of a research module which briefly threw the International Space Station out of control on Thursday a few hours after docking.

Russian space officials said a software glitch and possible lapse in human attention were to blame for the mishap that caused the entire space station to pitch out of its normal flight position 250 miles above the Earth with seven crew members aboard.

Footage published late on Saturday showed cosmonauts Oleg Novitsky and Pyotr Dubrov opening the hatches and giving a short tour inside the Nauka module, the Russian space agency Roscosmos said.

According to NASA‘s account of Thursday’s incident, the mission flight director immediately declared a spaceflight emergency as engineers on the ground struggled to restore stability to the sprawling research satellite.

NASA and Roscosmos each said that the seven crew members – two Russian cosmonauts, three U.S. astronauts and two others from Japan and France – were never in any immediate danger.

Roscosmos, which this week spoke of plans to launch another Russian module to the station in November, has suffered a series of mishaps and corruption scandals, including during the construction of the Vostochny Cosmodrome in the country’s far east where contractors were accused of embezzling state funds.

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