Microscopic roundabout directs light without a magnet

May 4 (UPI) — Circulators direct light on optical chips, a process essential to communication technology. The component relies on a tiny magnet, but miniaturizing magnets is difficult.

Enter the magnet-free optical circulator. The roundabout can route light without the assistance of a tiny magnet. Researchers say it’s the first of its kind.

Using a unique combination of entrance and exit ports, circulators ensure that light is directed to the proper place and that no light — or information — is lost on the path from one port to another.

“Light propagation is symmetric in nature, which means if light can propagate from A to B, the reverse path is equally possible. We need a trick to break the symmetry,” lead researcher Ewold Verhagen, scientist at the Dutch research institute AMOLF, said in a news release. “Usually this ‘trick’ is using centimeter-sized magnets to impart directionality and break the symmetric nature of light propagation. Such systems are difficult to miniaturize for use on photonic chips.”

Verhagen and his research partners, including scientists from the University of Texas, replaced the magnetized circulator with a microscale glass ring resonator. Structural vibrations control when light can exit and where.

“By shining light of a ‘control’ laser in the ring, light of a different color can excite vibrations through a force known as radiation pressure, but only if it propagates in the same direction as the control light wave,” Verhagen said. “Since light propagates differently through a vibrating structure than through a structure that is standing still, the optical force breaks symmetry in the same way as a magnetic field would.”

Scientists still had to find a way to ensure the propagated light exited at the proper port, the next available exit. They realized the control laser can use a phenomenon called optical interference to propagate the light out of a specific exit.

“We demonstrated this circulation in experiments, and showed that it can be actively tuned,” said postdoc John Mathew. “The frequency and power of the control laser allow the circulation to be turned on and off and change handedness.”

The breakthrough — detailed in the journal Nature Communications — could do more than improve communication technologies, it could also power quantum computers.

“The fact that the circulator can be actively controlled provides additional functionality as the optical circuits can be reconfigured at will,” Verhagen said.

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Scientists capture video of cells as they function inside organisms

April 20 (UPI) — Scientists have adapted an optics technique used by astronomers to render biological processes at both the cellular and sub-cellular level in unprecedented detail.

Researchers at the Howard Hughes Medical Institute, Boston Children’s Hospital and Harvard Medical School worked together to build a next-generation microscope powered by “guide star” technology.

“For the first time, we are seeing life itself at all levels inside whole, living organisms,” Tom Kirchhausen, a professor of cell biology and pediatrics at Harvard Medical School and a researcher at Boston Children’s Hospital, said in a news release.

The new microscope can be used to study almost any biological process or system in any kind of living organism. Scientists can use the microscope to render 3D images of a range biological phenomena in real-time.

The technology was originally designed to help large telescopes observe faraway galaxies, stars and planetary systems. The guide star refers to an artificial light source, a laser, that helps the adaptive optics system correct for atmospheric distortion.

Scientists successfully adapted the technology to work with a lattice light sheet microscope on much smaller scales. The hybrid technology allows scientists to probe deeper into tissue and cells by scanning a less-powerful layer of diffused light across biological samples.

As part of the initial tests, scientists used the microscope to survey the cells of a zebrafish. For the first time, scientists watched an immune cell swimming through the zebra fish’s ear, scooping up sugar particles along the way.

Until now, it was necessary to deploy high-powered lasers for such high-resolution images — but powerful beams can damage biological samples. The new technology allows scientists to study biological systems in vitro. Scientists were also able to watch human cancer cells migrating through the bloodstream of a zebrafish model.

Scientists say studying cells inside natural biological systems, inside real tissue and real organisms, is essential to truly understanding how cells and cellular processes function and evolve.

“This raises the nagging doubt that we are not seeing cells in their native state, happily ensconced in the organism in which they evolved,” said lead researcher Eric Betzig. “It’s often said that seeing is believing, but when it comes to cell biology, I think the more appropriate question is, ‘When can we believe what we see?'”

Betzig and his colleagues detailed their technological breakthrough in a new paper published this week in the journal Science.

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Virgin Galactic completes first rocket-powered Unity space craft launch

April 5 (UPI) — Virgin Galactic successfully launched and landed its Unity spacecraft by rocket power, completing its first powered flight in almost four years.

Richard Branson‘s space company shared a photo of the SpaceShipTwo model spacecraft as it blasted into the air above the Mojave Air and Space Port before going supersonic and landing safely.

“VSS Unity completed her first supersonic, rocket-powered flight this morning in Mojave, California. Another great test flight, another step closer to being,” Virgin Galactic wrote on Twitter.

Unity took off at about 8:02 a.m. as it was propelled to an altitude of 46,500 feet by the WhiteKnightTwo carrier aircraft, VMS Eve.

Eve then released Unity from under its wing and the SpaceShipTwo’s pilots Mark Stucky and Dave Mackay brought the spacecraft’s engines to life and propelled it into an 80 degree climb, accelerating to Mach 1.87 during the 30 seconds of rocket burn.

“On rocket shutdown, Unity continued an upwards coast to an apogee of 84,271 feet before readying for the downhill return,” Virgin Galactic said.

Once the spacecraft began to descend, the pilots raised its tail booms to a 60 degree angle from the fuselage into the “feathered” configuration, which was adopted after fatal 2014 VSS Enterprise test flight crash.

At 50,000 feet, the tail-booms were lowered again and the Unity glided toward a safe landing on the runway.

“The flight has generated valuable data on flight, motor and vehicle performance which our engineers will be reviewing,” Virgin Galactic said. “It also marks a key moment for the test flight program, entering now the exciting phase of powered flight and the expansion to full duration rocket burns.”

The newest SpaceShipTwo model was unveiled in February 2016, when the late professor Stephen Hawking gave the ship the name “Unity.”

In the future Virgin Galactic’s spacecraft will take passengers 68 miles above the Earth’s surface for a price of $ 250,000.

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New source of global nitrogen could help soil store more CO2

April 6 (UPI) — Until now, scientists thought plants got all their nitrogen from the atmosphere, but new research suggests Earth’s bedrock supplies as much as a quarter of the planet’s nitrogen.

The discovery, detailed this week in the journal Science, could change researchers’ understanding of the carbon cycle.

“Our study shows that nitrogen weathering is a globally significant source of nutrition to soils and ecosystems worldwide,” Ben Houlton, director of the Muir Institute at the University of California, Davis, said in a news release. “This runs counter [to] the centuries-long paradigm that has laid the foundation for the environmental sciences. We think that this nitrogen may allow forests and grasslands to sequester more fossil fuel CO2 emissions than previously thought.”

Nitrogen is essential to the carbon sequestration process, but until now, scientists thought ecosystems were limited to the small amount of nitrogen plants and soil pull from the atmosphere.

In order for nitrogen to leach out of bedrock and into the ecosystem, weathering must occur. Tectonic activity could free up nitrogen, researchers suggest, as could chemical weathering, which occurs when rainwater reacts with a rock’s minerals.

Mountains like the Himalayas and Andes are likely home to large amounts of nitrogen weathering, as are grasslands, tundra, deserts and woodlands.

Places with high levels of nitrogen weathering may warrant extra environmental protections.

“Geology might have a huge control over which systems can take up carbon dioxide and which ones don’t,” Houlton said. “When thinking about carbon sequestration, the geology of the planet can help guide our decisions about what we’re conserving.”

Scientists knew there was a missing nitrogen input somewhere because the atmosphere couldn’t account for the levels researchers were measuring in soils. But scientists couldn’t find it — until now.

“We show that the paradox of nitrogen is written in stone,” said researcher Scott Morford, a UC Davis grad student at the time of the study. “There’s enough nitrogen in the rocks, and it breaks down fast enough to explain the cases where there has been this mysterious gap.”

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You'll soon be able to sleep in space for just $792,000 a night

April 6 (UPI) — Space is scheduled to get its first luxury hotel thanks to Houston-based aerospace startup Orion Span. The company aims to launch its Aurora Station in late 2021.

“By early 2022, we will be hosting tourists, astronauts, space research, and manufacturing on board Aurora Station,” the company announced in a blog post.

A stay on the Aurora Station will run guests an estimated $ 792,000 a night. Staying just one night, however, likely won’t be an option.

“We’re not selling a hey-let’s-go-to-the-beach equivalent in space,” Frank Bunger, Orion Span’s founder and chief executive officer, told Bloomberg. “We’re selling the experience of being an astronaut. You reckon that there are people who are willing to pay to have that experience.”

Twelve-day stays will cost about $ 9.5 million per person, the company predicts.

The hotel will orbit Earth at a distance of 200 miles, circling the globe once every 90 minutes.

As of now, the company has a business model and basic plans for the construction of its luxury space hotel. But to make their plans a reality, they need to raise money.

According to Bloomberg, the startup has yet to team up with a launch provider. But Orion Span isn’t the only commercial space outfit with bold plans.

Another Texas-based company, Axiom Space, plans to put a commercial space station into orbit by 2024. Virgin Galactic wants to take tourists on shorter but slightly more affordable — at $ 250,000 a pop — trips through space. SpaceX has also said it plans to carry a pair of space tourists around the moon.

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Watch live: SpaceX to launch space station resupply mission

April 2 (UPI) — SpaceX is set to send another Dragon spaceship to the International Space Station on Monday afternoon. The cargo vessel will be launched into space by a Falcon 9 rocket.

The blastoff from South Florida’s Cape Canaveral Air Force Station is scheduled for 4:30 p.m. ET.

Monday’s launch will be SpaceX’s 14th space station resupply mission.

“Dragon will separate from Falcon 9’s second stage about 10 minutes after liftoff and attach to the space station on Wednesday, April 4,” SpaceX announced in an update. “Both Falcon 9 and the Dragon spacecraft for the CRS-14 mission are flight-proven.”

SpaceX will broadcast a live stream of the mission beginning 20 minutes before launch.

As usual, the cargo vessel will carry a combination of supplies, equipment and science experiments to the space station. Included among the science-related cargo is an experiment designed to study severe thunderstorms on Earth. Also included are a range of materials, coatings and components that will be exposed to the harsh space environment and monitored for damage.

Another experiment making its way to space is the Comparative Real-time Metabolic Activity Tracking for Improved Therapeutic Assessment Screening Panels. The study is designed to test the effects of microgravity on the synthesis and deployment of five different therapeutic compounds.

“This investigation determines the feasibility of developing improved pharmaceuticals in microgravity using a new method to test the metabolic impacts of drug compounds,” NASA said in an update. “This could lead to more effective, less expensive drugs.”

The Dragon cargo ship and its 5,800 pounds of supplies, hardware and science experiments will be received by the space station’s Canadarm2 robotic arm. The astronauts aboard ISS have been cleaning up to make room for the cargo and practicing for the vessel’s reception.

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