Tag Archives: NASA

Brighter Future For Us All: High-Fidelity Images of Sun’s Atmosphere Tell The Tale

A Southwest Research Institute-led team discovered never-before-detected, fine-grained structures in the Sun’s outer atmosphere, or corona. The team imaged this critical region in detail using sophisticated software techniques and longer exposures from the COR-2 camera onboard NASA’s Solar and Terrestrial Relations Observatory-A (STEREO-A).

The Sun’s outer corona is the source of the solar wind, the stream of charged particles that flow outward from the Sun in all directions. Measured near Earth, the magnetic fields embedded within the solar wind are intertwined and complex.

“Previous images showed the outer corona as a smooth structure, but in deep space, the solar wind is turbulent and gusty,” said SwRI’s Dr. Craig DeForest, a solar physicist and lead author of “The Highly Structured Outer Corona,” an article published by Astrophysical Journal July 18, 2018.

“Using new techniques to improve image fidelity, we realized that the corona is not smooth, but structured and dynamic. Every structure that we thought we understood turns out to be made of smaller ones and to be more dynamic than we thought.”

To understand the corona, DeForest and his colleagues started with extended exposures of STEREO-A’s coronagraph images – pictures of the Sun’s atmosphere produced by a special telescope that blocks out light from the bright solar disk.

The coronagraph is sensitive enough to image the corona in great detail, but in practice its measurements are polluted by noise both from the space environment and the instrument itself. The team’s key innovation was identifying and separating out that noise, boosting the signal-to-noise ratio and revealing the outer corona in unprecedented detail.

“We couldn’t tinker with the instrument itself, so we took a software approach, squeezing out the highest quality data possible by improving the data’s signal-to-noise ratio,” DeForest said. “We developed new filtering algorithms, designed and tested to delineate the true corona from the noisy measurements.”

The algorithms filtered out light and adjusted brightness. But the most challenging obstacle is inherent: blur due to the motion of the solar wind. “This technique adjusted images not just in space, not just in time, but in a moving coordinate system,” DeForest said.

“That allowed us to correct motion blur not just by the speed of the wind, but by how rapidly features changed in the wind.”

With the resulting unprecedented view of the corona, the team made several groundbreaking discoveries. For example, coronal streamers – magnetic loops that can erupt into coronal mass ejections that send blobs of solar material into space – are far more structured than previously thought.

“What we found is that there is no such thing as a single streamer,” DeForest said. “The streamers themselves are composed of myriad fine strands that, together, average to produce a brighter feature.”

Then there’s the theoretical Alfven surface – a proposed surface, or sheet-like layer where the gradually accelerating solar wind reaches a critical speed. But that’s not what DeForest’s team observed.

“What we found is that there isn’t a clean Alfven surface,” DeForest said. “There’s a wide ‘no-man’s land’ or `Alfven zone’ where the solar wind gradually disconnects from the Sun, rather than a single clear boundary.”

And the close look at the coronal structure also raised new questions. Techniques used to estimate the speed of the solar wind revealed that the wind suddenly changes its character at a distance of around 10 solar radii, well within the conventional boundary of the corona itself.

“Some interesting physics is happening around there,” DeForest said. “We don’t know what it is yet, but we do know that it is going to be interesting.”

These first observations will provide key insight for NASA’s upcoming Parker Solar Probe, the first-ever mission to gather measurements from within the outer solar corona.

First Space Tourist Flights Could Come In 2019

The two companies leading the pack in the pursuit of space tourism say they are just months away from their first out-of-this-world passenger flights — though neither has set a firm date.

Virgin Galactic, founded by British billionaire Richard Branson, and Blue Origin, by Amazon creator Jeff Bezos, are racing to be the first to finish their tests — with both companies using radically different technology.

– Moments of weightlessness –

Neither Virgin nor Blue Origin’s passengers will find themselves orbiting the Earth: instead, their weightless experience will last just minutes. It’s an offering far different from the first space tourists, who paid tens of millions of dollars to travel to the International Space Station (ISS) in the 2000s.

Having paid for a much cheaper ticket — costing $250,000 with Virgin, as yet unknown with Blue Origin — the new round of space tourists will be propelled dozens of miles into the atmosphere, before coming back down to Earth. By comparison, the ISS is in orbit 250 miles (400 kilometers) from our planet.

The goal is to approach or pass through the imaginary line marking where space begins — either the Karman line, at 100 kilometers or 62 miles, or the 50-mile boundary recognized by the US Air Force.

At this altitude, the sky looks dark and the curvature of the earth can be seen clearly.

– Virgin Galactic –

With Virgin Galactic, six passengers and two pilots are boarded onto SpaceShipTwo VSS Unity, which resembles a private jet.

The VSS Unity will be attached to a carrier spacecraft — the WhiteKnightTwo — from which it will then detach at around 49,000 feet (15,000 meters.) Once released, the spaceship will fire up its rocket, and head for the sky.

Then, the passengers will float in zero-gravity for several minutes, before coming back to Earth.

The descent is slowed down by a “feathering” system that sees the spacecraft’s tail pivot, as if arching, before returning to normal and gliding to land at Virgin’s “spaceport” in the New Mexico desert.

In total, the mission lasts between 90 minutes and two hours. During a May 29 test in California’s Mojave desert, the spaceship reached an altitude of 21 miles, heading for space.

In October 2014, the Virgin spaceship broke down in flight due to a piloting error, killing one of two pilots on board. The tests later resumed with a new craft.

The company has now also reached a deal to open a second “spaceport” at Italy’s Tarente-Grottaglie airport, in the south of the country.

Branson in May told BBC Radio 4 that he hoped to himself be one of the first passengers in the next 12 months. About 650 people make up the rest of the waiting list, Virgin told AFP.

– Blue Origin –

Blue Origin, meanwhile, has developed a system closer to the traditional rocket: the New Shepard.

On this journey, six passengers take their place in a “capsule” fixed to the top of a 60-foot-long rocket. After launching, it detaches and continues its trajectory several miles toward the sky. During an April 29 test, the capsule made it 66 miles.

After a few minutes of weightlessness, during which passengers can take in the view through large windows, the capsule gradually falls back to earth with three large parachutes and retrorockets used to slow the spacecraft.

From take-off to landing, the flight took 10 minutes during the latest test.

Until now, tests have only been carried out using dummies at Blue Origin’s West Texas site.

Company officials were recently quoted as saying the first tests with Blue Origin astronauts would take place “at the end of this year,” with tickets for the public expected to go on sale in 2019.

But in comments to AFP Friday, the company struck a more cautious note.

“We have not set ticket pricing and have had no serious discussions inside of Blue on the topic,” the firm said. “We have a flight test schedule and schedules of those types always have uncertainties and contingencies. Anyone predicting dates is guessing.”

– What’s next? –

SpaceX and Boeing are developing their own capsules to transport NASA astronauts, most likely in 2020, after delays — a significant investment that the companies will likely make up for by offering private passenger flights.

“If you’re looking to go to space, you’ll have quadruple the menu of options that you ever had before,” Phil Larson, assistant dean at the University of Colorado, Boulder’s College of Engineering and Applied Science, told AFP.

Longer term, the Russian firm that manufactures Soyuz rockets is studying the possibility of taking tourists back to the ISS. And a US start-up called Orion Span announced earlier this year it hopes to place a luxury space hotel into orbit within a few years — but the project is still in its early stages.

SpaceX Set To Launch Planet Hunter TESS On Monday

With the crippled Kepler orbital equipment almost out of fuel, NASA is preparing the launch of its newest planet-hunting spacecraft, TESS.

TESS, short for Transiting Exoplanet Survey Satellite, will be carried into space by SpaceX’s Falcon 9 rocket on April 16. With a little help from the moon’s gravity, the satellite will achieve a high Earth orbit, offering the probe wide, unobstructed views of the night sky. The probe will orbit Earth twice for every one lunar orbit.

While TESS’s scientific mission is largely the same as Kepler’s — image transiting exoplanets — the probe will use a different approach. Whereas Kepler focused on small fields of view for long periods of time, TESS will take a wider, more comprehensive view.

“TESS is designed to image almost all of the night sky — using four wide angle cameras — in long vertical strips called sectors,” Natalia Guerrero, MIT scientist and researcher on the TESS mission, told UPI.

TESS scientists have divided the sky into long strips called sectors. Each hemisphere contains 13 sectors, and over the next three years, TESS will survey, sector by sector, the Southern Hemisphere and then the Northern Hemisphere.

During each sector scan, TESS’s four cameras will capture 30-minute exposures. The four images will be stacked on top of each other by the satellite’s computer and transmitted back to Earth.

In addition to organizing the sky into sectors, TESS scientists have identified 200,000 especially bright stars likely to host transiting exoplanets. Each stellar target is highlighted by a so-called postage stamp.

Exposures of each postage stamp will be stacked on top of each other every two minutes and beamed back to Earth. These postage stamp observations are expected to identify planetary systems located much closer to Earth than those found by Kepler.

Data captured by TESS will go through the same image-processing pipeline used for Kepler observations. Basic algorithms will process images and identify the dimming patterns created when exoplanets pass across the face of their host star.

Scientists will review the transit events identified via computer analysis and highlight targets for follow-up observations.

“From the depth of the transit and the frequency light curve, we can back out the size of the planet and distance from its host star,” Guerrero said.

But, like Kepler, TESS is designed to survey the sky, not carry out in-depth investigations. Scientists will rely on other telescopes, both ground and space-based, to observe transiting objects in greater detail. Through follow-up investigations, astronomers will be able to estimate an exoplanet’s mass and the composition of its atmosphere, as well as its habitability.

TESS scientists will focus much of their analysis on the two-minute cadence of images of postage stamped targets, but the satellite’s biggest surprises may be more likely to be revealed by the full frame images. In addition to capturing transits, the full-frame images will record observations of thousands of stars.

“The full frame images will serve as really rich repositories of data,” Guerrero said. “They will be made public and will be a wonderful opportunity for the astronomical community and really any interested parties.”

“We’re very excited about the citizen science efforts that will be inspired by these images,” Guerrero said.

Aussies Seek Information About Interstellar Visitor

A telescope in outback Western Australia has been used to listen to a mysterious cigar-shaped object that entered our solar system late last year.

The unusual object – known as ‘Oumuamua – came from another solar system, prompting speculation it could be an alien spacecraft. So astronomers went back through observations from the Murchison Widefield Array (MWA) telescope to check for radio transmissions coming from the object between the frequencies of 72 and 102 MHz – similar to the frequency range in which FM radio is broadcast.

While they did not find any signs of intelligent life, the research helped expand the search for extraterrestrial intelligence (SETI) from distant stars to objects closer to home.

When ‘Oumuamua was first discovered, astronomers thought it was a comet or an asteroid from within the solar system. But after studying its orbit and discovering its long, cylindrical shape, they realised ‘Oumuamua was neither and had come from interstellar space.

Telescopes around the world trained their gaze on the mysterious visitor in an effort to learn as much as possible before it headed back out of the solar system, becoming too faint to observe in detail.

John Curtin Distinguished Professor Steven Tingay, from the Curtin University node of the International Centre for Radio Astronomy Research (ICRAR), said the MWA team did not initially set out to find ‘Oumuamua.

“We didn’t set out to observe this object with the MWA but because we can see such a large fraction of the sky at once, when something like this happens, we’re able to go back through the data and analyse it after the fact,” Professor Tingay said.

“If advanced civilizations do exist elsewhere in our galaxy, we can speculate that they might develop the capability to launch spacecraft over interstellar distances and that these spacecraft may use radio waves to communicate. Whilst the possibility of this is extremely low, possibly even zero, as scientists it’s important that we avoid complacency and examine observations and evidence without bias.”

The MWA is located in Western Australia’s remote Murchison region, one of the most radio-quiet areas on the planet and far from human activity and radio interference caused by technology. It is made up of thousands of antennas attached to hundreds of “tiles” that dot the ancient landscape, relentlessly observing the heavens day after day, night after night.

Professor Tingay said the research team was able to look back through all of the MWA’s observations from November, December and early January, when ‘Oumuamua was between 95 million and 590 million kilometres from Earth.

“We found nothing, but as the first object of its class to be discovered, `Oumuamua has given us an interesting opportunity to expand the search for extra-terrestrial intelligence from traditional targets such as stars and galaxies to objects that are much closer to Earth. This also allows for searches for transmitters that are many orders of magnitude less powerful than those that would be detectable from a planet orbiting even the most nearby stars.”

‘Oumuamua was first discovered by the Pan-STARRS project at the University of Hawaii in October. Its name loosely means “a messenger that reaches out from the distant past” in Hawaiian, and is the first known interstellar object to pass through our solar system.

Combining observations from a host of telescopes, scientists have determined that ‘Oumuamua is most likely a cometary fragment that has lost much of its surface water because it was bombarded by cosmic rays on its long journey through interstellar space.

Researchers have now suggested there could be more than 46 million similar interstellar objects crossing the solar system every year. While most of these objects are too far away to study with current technologies, future telescopes such as the Square Kilometre Array (SKA) will enable scientists to understand more about these interstellar interlopers.

“So once the SKA is online,” said Professor Tingay, “we’ll be able to look at large numbers of objects and partially balance out the low probability of a positive detection.”

Virgin Galactic Success! First Rocket-powered Unity Space Craft Launches & Returns Crew Safely To Ground

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.