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'Aliens vs. Avengers' pits Marvel superheroes against acid-spewing xenomorphs
As Bird Flu Spreads through Cows, Is Pasteurized Milk Safe to Drink?
H5N1 influenza virus particles have been detected in commercially sold milk, but it’s not clear how the virus is spreading in cattle or whether their milk could infect humans
Week in images: 22-26 April 2024
Week in images: 22-26 April 2024
Discover our week through the lens
Asteroid that broke up over Berlin was fastest-spinning one ever seen
Asteroid that broke up over Berlin was fastest-spinning one ever seen
People Keep Secrets Because They Overestimate Harsh Judgments
Research suggests that people tend to exaggerate how critically they will be viewed if they reveal negative information about themselves to others
NASA’s ORCA, AirHARP Projects Paved Way for PACE to Reach Space
It took the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission just 13 minutes to reach low-Earth orbit from Cape Canaveral Space Force Station in February 2024. It took a network of scientists at NASA and research institutions around the world more than 20 years to carefully craft and test the novel instruments that allow PACE to study the ocean and atmosphere with unprecedented clarity.
In the early 2000s, a team of scientists at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, prototyped the Ocean Radiometer for Carbon Assessment (ORCA) instrument, which ultimately became PACE’s primary research tool: the Ocean Color instrument (OCI). Then, in the 2010s, a team from the University of Maryland, Baltimore County (UMBC), worked with NASA to prototype the Hyper Angular Rainbow Polarimeter (HARP), a shoebox-sized instrument that will collect groundbreaking measurements of atmospheric aerosols.
Neither PACE’s OCI nor HARP2 — a nearly exact copy of the HARP prototype — would exist were it not for NASA’s early investments in novel technologies for Earth observation through competitive grants distributed by the agency’s Earth Science Technology Office (ESTO). Over the last 25 years, ESTO has managed the development of more than 1,100 new technologies for gathering science measurements.
“All of this investment in the tech development early on basically made it much, much easier for us to build the observatory into what it is today,” said Jeremy Werdell, an oceanographer at NASA Goddard and project scientist for PACE.
Charles “Chuck” McClain, who led the ORCA research team until his retirement in 2013, said NASA’s commitment to technology development is a cornerstone of PACE’s success. “Without ESTO, it wouldn’t have happened. It was a long and winding road, getting to where we are today.”
Left to right: Gerhard Meister, Bryan Monosmith, and Chuck McClain are shown here at NASA’s Goddard Space Flight Center in Greenbelt, Md., in 2015 with the Ocean Radiometer for Carbon Assessment (ORCA) prototype that led to the Ocean Color Instrument (OCI) aboard NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission.NASA/Bill Hrybyk
It was ORCA that first demonstrated a telescope rotating at a speed of six revolutions per second could synchronize perfectly with an array of charge-coupled devices — microchips that transform telescopic projections into digital images. This innovation made it possible for OCI to observe hyperspectral shades of ocean color previously unobtainable using space-based sensors.
But what made ORCA especially appealing to PACE was its pedigree of thorough testing. “One really important consideration was technology readiness,” said Gerhard Meister, who took over ORCA after McClain retired and serves as OCI instrument scientist. Compared to other ocean radiometer designs that were considered for PACE, “we had this instrument that was ready, and we had shown that it would work.”
Technology readiness also made HARP an appealing solution to PACE’s polarimeter challenge. Mission engineers needed an instrument powerful enough to ensure PACE’s ocean color measurements weren’t jeopardized by atmospheric interference, but compact enough to fly on the PACE observatory platform.
By the time Vanderlei Martins, an atmospheric scientist at UMBC, first spoke to Werdell about incorporating a version of HARP into PACE in 2016, he had proven the technology with AirHARP, an airplane-mounted version of HARP, and was using an ESTO award to prepare HARP CubeSat for space.
HARP2 relies on the same optical system developed through AirHARP and HARP CubeSat. A wide-angle lens observes Earth’s surface from up to 60 different viewing angles with a spatial resolution of 1.62 miles (2.6kilometers) per pixel, all without any moving parts. This gives researchers a global view of aerosols from a tiny instrument that consumes very little energy.
HARP2, short for Hyper Angular Rainbow Polarimeter 2, undergoes calibration testing prior to launch aboard PACE.NASA/Denny Henry
Were it not for NASA’s early support of AirHARP and HARP CubeSat, said Martins, “I don’t think we would have HARP2 today.” He added: “We achieved every single goal, every single element, and that was because ESTO stayed with us.”
That support continues making a difference to researchers like Jessie Turner, an oceanographer at the University of Connecticut who will use PACE to study algal blooms and water clarity in the Chesapeake Bay.
“For my application that I’m building for early adopters of PACE data, I actually think that polarimeters are going to be really useful because that’s something we haven’t fully done before for the ocean,” Turner said. “Polarimetric data can actually help us see what kind of particles are in the water.”
Without the early development and test-drives of the instruments from McClain’s and Martins’ teams, PACE as we know it wouldn’t exist.
“It all kind of fell in place in a timely manner that allowed us to mature the instruments, along with the science, just in time for PACE,” said McClain.
To explore current opportunities to collaborate with NASA on new technologies for studying Earth, visit ESTO’s open solicitations page here.
By Gage Taylor
NASA’s Goddard Space Flight Center, Greenbelt, Md.
How Unhealthy Are Ultra-Processed Foods?
Processed foods have been blamed for many health problems, but dietary research is tricky and nuanced
Global warming could make tides higher as well as raising sea levels
Global warming could make tides higher as well as raising sea levels
Cicadas Are Basically Safe for You—And Your Dog—to Eat. Here’s What to Know
Here’s what a chef, a vet and two anthropologists have to say about eating periodical cicadas
The Threat of a Solar Superstorm Is Growing—And We’re Not Ready
Someday an unlucky outburst from our sun could strike Earth and fry most of our electronics—and we’ve already had some too-close-for-comfort near misses
Black Holes Can Halt Star Formation in Massive Galaxies
It’s difficult to actually visualise a universe that is changing. Things tend to happen at snails pace albeit with the odd exception. Take the formation of galaxies growing in the early universe. Their immense gravitational field would suck in dust and gas from the local vicinity creating vast collections of stars. In the very centre of these young galaxies, supermassive blackholes would reside turning the galaxy into powerful quasars. A recent survey by the James Webb Space Telescope (JWST) reveals that black holes can create a powerful solar wind that can remove gas from galaxies faster than they can form into stars, shutting off the creation of new stars.
To remove the confusion and mystique around black holes, they are the corpse of massive stars. When supermassive stars collapse at the end of their lives their core turns into a point source that is so incredibly dense that even light, travelling at 300,000 kilometres per second, is unable to escape. It’s believed that many galaxies have supermassive black holes at their core.
Swift scene change to the earlier part of the life of a star. Fusion in the core generates incredible amounts of energy as new elements are synthesised. Along with new elements, heat and light, a powerful outflow of electrically charged particles rushes away and permeates the surrounding space. Here in our Solar System, charged particles rush Earthward and on arrival we experience the glorious display of the northern lights.
Visualization of the solar wind encountering Earth’s magnetic “defenses” known as the magnetosphere. Clouds of southward-pointing plasma are able to peel back layers of the Sun-facing bubble and stack them into layers on the planet’s nightside (center, right). The layers can be squeezed tightly enough to reconnect and deliver solar electrons (yellow sparkles) directly into the upper atmosphere to create the aurora. Credit: JPLA team of astronomers using the JWST have found that, over 90 percent of the wind that flows through a distant galaxy is made of neutral gas and to date, has been invisible. Until recently it was only possible to detect ionised gas – gas which carries an electric charge – which is warm. The neutral gas in the study revealed that neutral gas was cold but JWST was able to detect it.
The powerful outflow of neutral gas is thought to come from the supermassive blackholes at the core of some galaxies at the edge of the Universe. The team, led by Dr Rebecca Davies from Swinburne University first identified that black hole driven outflow in a distant galaxy over 10 billion light years away. The paper published in Nature explains how ‘The outflow is removing gas faster than gas is being converted into stars, indicating that the outflow is likely to have a very significant impact on the evolution of the galaxy.’
With a lack of gas and dust, star formation will slow and eventually stop. Just like a forest that always has new trees growing to replace old, dying trees, so galaxies usually have star formation to replace dying stars. Ultimately the forest, and a galaxy will be unable to grow and develop and eventually become static and slowly die with the final stars blinking out.
This is a JWST view of the Crab Nebula. Like other supernovae, a star exploded to create this scene.The result is a rapidly spinning neutron star (a pulsar) at its heart, surrounded by material rushing out from the site of the explosion. SN 2022jli could have either a neutron star or a black hole orbiting with a companion star.The team found that the active galactic nuclei with supermassive black holes are the driving force behind this outflow of gas. Those with the most massive black holes can even strip the host galaxy of all the star forming gasses playing a major role in the evolution of the galaxy.
Source : New JWST observations reveal black holes rapidly shut off star formation in massive galaxies
The post Black Holes Can Halt Star Formation in Massive Galaxies appeared first on Universe Today.
Satellite images overlay 2024 and 2017 total solar eclipses sweeping across US
A Long-Awaited Climate Experiment Is Poised to Launch in the Amazon. What Will It Find?
Ahead of a project to spray carbon dioxide into jungle plots, researchers contemplate what its results might signal about the forest’s future.
This Week's Sky at a Glance, April 26 – May 5
All the planets now huddle around our line of sight toward the Sun. However, these moonless evenings present us the Spring Triangle, the Great Diamond with a sugar sprinkle on its edge, and the Pointers aligned vertically.
The post This Week's Sky at a Glance, April 26 – May 5 appeared first on Sky & Telescope.