Feed aggregator
AI that determines risk of death helps save lives in hospital trial
Highly precise atomic clocks could soon get even better. Here's how
NASA Uses Small Engine to Enhance Sustainable Jet Research
3 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater) The DGEN380 Aero-Propulsion Research Turbofan (DART) is a small-scale jet engine NASA uses to test new aviation technology. DART is seen here inside its host facility, the Aero-Acoustic Propulsion Laboratory at NASA’s Glenn Research Center in Cleveland. This soundproofed chamber ensures researchers can understand the level of noise the engine is producing, as well as keeping the volume low outside.NASA/Bridget Caswell
Located inside a high-tech NASA laboratory in Cleveland is something you could almost miss at first glance: a small-scale, fully operational jet engine to test new technology that could make aviation more sustainable.
The engine’s smaller size and modestly equipped test stand means researchers and engineers can try out newly designed engine components less expensively compared to using a more costly full-scale jet engine test rig.
Named DGEN380 Aero-Propulsion Research Turbofan, or DART, the engine is tiny enough to fit on a kitchen table, measuring at just 4.3 feet (1.3 meters) long. That’s about half the length of engines used on single-aisle airliners.
DART – not to be confused with NASA’s asteroid redirect mission of the same name – enables the agency to boost its sustainable aviation technology research because of its accessibility.
A hidden gem located inside the Aero-Acoustic Propulsion Laboratory at NASA’s Glenn Research Center in Cleveland, the DART engine was made by a French company named Price Induction (now Akira) and was acquired by NASA in 2017.
“DART’s small size makes it appealing,” said Dan Sutliff, who coordinates research for the engine at NASA Glenn. “It’s a great way to explore new technology that hasn’t yet reached the level of a full-scale operation.”
Small Steps Towards Big GoalsSeveral key NASA activities studying jet engines used DART in the past.
For example, it helped researchers learn more about incorporating materials that can help reduce engine noise. These technologies could be incorporated for use in next-generation airliners to make them quieter.
Now, NASA researchers plan to use the DART engine to investigate ideas that could help develop new ultra-efficient airliners for use during the 2030s and beyond. If all goes well, the technology could proceed to more exhaustive tests involving larger facilities such as NASA’s wind tunnels.
“DART is a critical bridge between a design and a wind tunnel test,” Sutliff said. “Technologies that work well here have a greater chance of achieving successful inclusion on future aircraft engines. The test rig helps NASA save resources and contribute to protecting our environment.”
DART tests are run from the Mobile Control Unit – a large van converted into a high-tech control facility with video monitors reporting live data from the engine. In this image, two engineers supervise an engine test, with the nearest researcher operating DART’s thrust lever.NASA/Bridget Caswell
Among its features, DART has a high bypass ratio, which is a measure of how much air passes through the turbofan and around the main core of the engine as opposed to entering it. Having a high bypass ratio means that DART is more characteristic of larger high-bypass ratio engines on commercial aircraft.
This design is more fuel efficient than other jet engines and makes DART ideal for testing new propulsion methods alongside NASA’s efforts in developing a small-core, fuel efficient jet engine for commercial airliners in the 2030s.
The DART engine also can test many other aspects of a jet engine including engine noise, operating controls, coatings used to protect engine parts, sensors and other instrumentation, and much more.
More information can be found on NASA’s Aero-Acoustic Propulsion Laboratory webpage.
About the AuthorJohn GouldAeronautics Research Mission DirectorateJohn Gould is a member of NASA Aeronautics' Strategic Communications team at NASA Headquarters in Washington, DC. He is dedicated to public service and NASA’s leading role in scientific exploration. Prior to working for NASA Aeronautics, he was a spaceflight historian and writer, having a lifelong passion for space and aviation.
Facebook logo @NASA @NASA Instagram logo @NASA Linkedin logo @NASA Explore More 5 min read Updates from NASA’s HyTEC Engine Core Project Show Progress Article 11 months ago 3 min read Sustainable Flight National Partnership Article 2 years ago 5 min read University Researchers Moving Electrified Aviation Forward with NASA Article 1 year ago Keep Exploring Discover More Topics From NASAMissions
Humans in Space
Climate Change
Aeronautics STEM
Share Details Last Updated Apr 26, 2024 EditorJim BankeContactBrian Newbacherbrian.t.newbacher@nasa.gov Related TermsTwo new satellites join the Galileo constellation
The European Galileo navigation system has two more satellites in orbit following their launch in the early morning of Sunday, 28 April, at 01:34 BST/02:34 CEST. With 30 satellites now in orbit, Galileo is expanding its constellation, increasing the reliability, robustness and, ultimately, the precision, benefiting billions of users worldwide.
Webb captures iconic Horsehead Nebula in unprecedented detail
The NASA/ESA/CSA James Webb Space Telescope has captured the sharpest infrared images to date of one of the most distinctive objects in our skies, the Horsehead Nebula. The observations show a part of the iconic nebula in a whole new light, capturing its complexity with unprecedented spatial resolution.
The nebula formed from a collapsing interstellar cloud of material, and glows because it is illuminated by a nearby hot star. The gas clouds surrounding the Horsehead have already dissipated, but the jutting pillar is made of thick clumps of material that is harder to erode. Astronomers estimate that the Horsehead has about five million years left before it too disintegrates. Webb’s new view focuses on the illuminated edge of the top of the nebula’s distinctive dust and gas structure.
Read more about the new Webb observations
This image showcases three views of the Horsehead Nebula, which resides in the constellation Orion (The Hunter), in the western side of the Orion B molecular cloud. Rising from turbulent waves of dust and gas is the Horsehead Nebula, otherwise known as Barnard 33, roughly 1300 light-years away.
The first image (left), released in November 2023, features the Horsehead Nebula as seen by ESA’s Euclid telescope. Euclid captured this image of the Horsehead in about one hour, which showcases the mission's ability to very quickly image an unprecedented area of the sky in high detail. You can learn more about this image here.
The second image (middle) shows the NASA/ESA Hubble Space Telescope’s infrared view of the Horsehead Nebula, which was featured as the telescope’s 23rd anniversary image in 2013. This image captures plumes of gas in the infrared and reveals a beautiful, delicate structure that is normally obscured by dust. You can learn more about this image here.
The third image (right) features a new view of the Horsehead Nebula from the NASA/ESA/CSA James Webb Space Telescope’s NIRCam (Near-InfraRed Camera) instrument. It is the sharpest infrared image of the object to date, showing a part of the iconic nebula in a whole new light, and capturing its complexity with unprecedented spatial resolution.
[Image description: A collage of three images of the Horsehead Nebula. In the left image labelled “Euclid (Visible-Infrared)”, the Nebula is seen amongst its surroundings. A small box around it connects to the second image labelled “Hubble (Infrared)”, where the Nebula is zoomed in on. A portion of the Nebula’s head has another box, which leads with a callout to the third image, labelled “Webb (Infrared)”, of that area.]
Image-generating AI creates uncanny optical illusions
Image-generating AI creates uncanny optical illusions
Psyche is Still Sending Data Home at Broadband Speeds
When I heard about this I felt an amused twinge of envy. Over the last year I have been using an unimpressive 4G broadband service and at best get 20 Mbps, NASA’s Psyche mission has STILL been getting 23 Mbps at 225 million km away! It’s all thanks to the prototype optical transmission system employed on the probe. It means it can get up to 100 times more data transmission rate than usual radio.
NASA’s Pysche mission is on its way to explore the metal rich asteroid between the orbits of Mars and Jupiter called, not surprisingly Psyche. The intriguing thing about the asteroid is that it seems to be the iron rich core of an unformed planet. The spacecraft carried a wealth of scientific instruments to explore the asteroid including an imaging rig, gamma ray and neutron spectrometer, magnetometer and an X-band Gravity platform.
It began its two year journey on 13 October with its destination, a tiny world that may help us unravel some of the mysteries of the formation of our Solar System. The theory that Psyche is a failed planetary core is not certain so this will be one of the first of its mission objectives; is it simply unmelted metal or was it a core. In order to understand this it’s necessary to work out its age. Secondary to the origin, other objectives are to explore the composition and its topography across the surface.
Asteroid Psuche was discovered in March 1852 by Italian astronomer Annibale de Gasparis. Because he discovered it, he was allowed to name it and settled on Psyche after the Greek goddess of the soul. It orbits the Sun at a distance of between 378 million to 497 million kilometres and takes about 5 Earth years to complete an orbit. Shaped like a potato, or perhaps more accurately classed as ‘irregular’ it is actually a little ellipsoid in shape measuring 280 km across wide at its widest part and 232 km across long.
Illustration of the metallic asteroid Psyche. Credit: Peter Rubin/NASA/JPL-Caltech/ASUOf more interest than the objectives perhaps (although I for one am looking forward to learn more about this wonderful asteroid) was the trial communication system. The newly developed Deep Space Optical Communications technology (DSOC) is not the primary communications platform but it is there as a prototype.
The optical system which relies upon laser technology successfully sent back engineering data at a distance of 226 million kilometres. Perhaps more impressively though, the spacecraft has shown that it can transmit at a rate of 267 Mbps (YES you read that right, just over quarter of a Gbps!) The impressive download speed was achieved on 11 December last year when a 15 second ultra high definition video was sent to Earth. Sadly though, as the spacecraft recedes, its data transmission capability will reduce. Still far better than normal radio communications though.
Using a powerful modulated laser, the Optical Communication Telescope Laboratory in California will be able to send data at a low rate to Psyche. To receive data, a photon counting receiver has been installed at the Caltech Palomar Observatory to pickup information sent by the spacecraft. Communication has always been a great challenge in space exploration and, whilst we cannot reduce transit time for data, we can improve the amount of data sent at any one time. A great step forward in space exploration.
Source : NASA’s Optical Comms Demo Transmits Data Over 140 Million Miles
The post Psyche is Still Sending Data Home at Broadband Speeds appeared first on Universe Today.
LIVE SpaceX Starlink Launch
Uh oh. Hubble's Having Gyro Problems Again
The Hubble Space Telescope has gone through its share of gyroscopes in its 34-year history in space. Astronauts replaced the gyros during the last servicing mission in 2009, bringing it back up to six (three with three spares), but they only last so long. Last week, HST went into safe mode because one of the gyros experienced fluctuations in power. NASA paused the telescope’s science operations today to investigate the fluctuations and perhaps come up with a fix.
With this one gyro experiencing problems, only two of the gyros remain fully operational. HST works best with three gyros, and so engineers are working to understand the issue and hopefully figure out a way to fix it remotely. However, several years ago, engineers figured out a way to still conduct science operations with only a single gyro.
HST entered safe mode on April 23, 2024 when the one gyro sent faulty readings. This particular gyro also caused Hubble to enter safe mode last November after returning similar faulty readings. The gyroscopes are part of Hubble’s Pointing Control System, which includes three Fine Guidance Sensors, reaction wheels and the gyros. This allows Hubble to track stars with incredible accuracy, helping the telescope find its way as it scans the heavens, as well as keep Hubble locked onto to its targets.
To work correctly, Hubble must be able to stay focused on a target without deviating more than 7/1000th of an arcsecond, or about the width of a human hair seen at a distance of a mile.
Hubble team created a contingency plan in preparation for a time when the spacecraft might find itself with less than three working gyros again. The team developed a two-gyro mode that substitutes other sensors for one missing gyro. Although less efficient, two-gyro mode allows Hubble to continue collecting ground-breaking science data.
The end of a Hubble gyro reveals the hair-thin wires known as flex leads. They carry data and electricity inside the gyro. Credit: NASANASA said that Hubble gyros fail over time, usually because of “wear and tear” of thin (less than the width of a human hair), metal wires, called flex leads that carry power in, and data out, of the mechanism. Hubble’s flex leads pass through a thick fluid inside the gyro. Over time, the flex leads begin to corrode and can physically bend or break.
During its 34-year history, Hubble has had eight out of 22 gyros fail due to a corroded flex lead. For example, in 1999, four out of six gyros had failed, with the last one failing about a month before a servicing mission was scheduled to replace them (and do other upgrades to the telescope). This meant Hubble sat in safe mode waiting for the space shuttle and astronauts to arrive.
Engineers developed a two-gyro mode when the final planned Hubble servicing mission was (temporarily) canceled following the space shuttle Columbia disaster. The mission was reinstated after outcry from scientists and the public, and so NASA figured out a way to mitigate the risks of flying the space shuttle. Servicing Mission 4 replaced all six gyros one last time in 2009.
With his feet firmly anchored on the shuttle’s robotic arm, astronaut Mike Good maneuvers to retrieve the tool caddy required to repair the Space Telescope Imaging Spectrograph during the final Hubble servicing mission in May 2009. Periodic upgrades have kept the telescope equipped with state-of-the-art instruments, which have given astronomers increasingly better views of the cosmos. Credits: NASAHowever, during the time it was thought no future servicing mission would happen, the observatory was proactively put into two-gyro mode to prolong its life. During this time, the team also devised a one-gyro mode, which could further extend Hubble’s life if needed.
“We knew gyros would be a limiting factor so we started to working on a reduced gyro mode to extend their life,” the director of the Space Telescope Science Institute Ken Sembach told me back in 2015 for my book, “Incredible Stories From Space.” “As it turned out, we did need that reduced gyro mode, and now they aren’t [as big of a] limiting factor for Hubble because we now know how to use the gyro resources in a new way. That added a longer life to the mission we didn’t think we would have.”
While the difference between two-gyro mode and one gyro-mode is negligible, one-gyro mode provides the option to have one of the remaining gyros placed in reserve. As of now, three of the six gyros onboard Hubble have had a flex lead fail and are no longer functional. NASA has not announced if the faulty readings are due to flex lead fail or another issue. If this gyro fails, the team will invoke one-gyro mode.
NASA did say that all of the science instruments are in good shape and they anticipate Hubble will “continue making groundbreaking discoveries, working with other observatories throughout this decade and possibly into the next.”
Hubble launched in 1990, and recently celebrated its 34th anniversary. While everyone expected HST would revolutionize astronomy, I don’t think anyone expected it would continue to be such a productive, world-class observatory even more than a thirty years after it launched. But, please, let’s keep it going for as long as possible!
The post Uh oh. Hubble's Having Gyro Problems Again appeared first on Universe Today.