NASA Astronomy Picture of the Day

December 27, 2024

Planet Earth at Twilight

No sudden, sharp boundary marks the passage of day into night in this gorgeous view of ocean and clouds over our fair planet Earth. Instead, the shadow line or terminator is diffuse and shows the gradual transition to darkness we experience as twilight. With the Sun illuminating the scene from the right, the cloud tops reflect gently reddened sunlight filtered through the dusty troposphere, the lowest layer of the planet's nurturing atmosphere. A clear high altitude layer, visible along the dayside's upper edge, scatters blue sunlight and fades into the blackness of space. This picture was taken from the International Space Station orbiting at an altitude of 211 nautical miles. Of course from home, you can check out the Earth Now.

https://apod.nasa.gov/apod/astropix.html

https://www.nasa.gov/centers-and-facilities/nesc/mechanical-systems-tdt-support-reaches-across-nasa-programs/

https://www.nasa.gov/centers-and-facilities/nesc/nesc-assists-in-heatshield-investigation/

Mechanical Systems TDT Support Reaches Across NASA Programs

Dec 26, 2024

The NESC Mechanical Systems TDT provides broad support across NASA’s mission directorates.

We are a diverse group representing a variety of sub-disciplines including bearings, gears, metrology, lubrication and tribology, mechanism design, analysis and testing, fastening systems, valve engineering, actuator engineering, pyrotechnics, mechatronics, and motor controls.

In addition to providing technical support, the TDT owns and maintains NASA-STD-5017, “Design and Development Requirements for Space Mechanisms.”

Mentoring the Next Generation

The NESC Mechanical Systems TDT actively participates in the Structures, Loads & Dynamics, Materials, and Mechanical Systems (SLAMS) Early Career Forum that mentors early-career engineers.

The TDT sent three members to this year’s forum at WSTF, where early-career engineers networked with peers and NESC mentors, gave presentations on tasks they worked on at their home centers, and attended splinter sessions where they collaborated with mentors.

New NASA Valve Standard to Reduce Risk and Improve Design and Reliability

Valve issues have been encountered across NASA’s programs and continue to compromise mission performance and increase risk, in many cases because the valve hardware was not qualified in the environment as specified in NASA-STD-5017.

To help address these issues, the Mechanical Systems TDT is developing a NASA standard for valves.

The TDT assembled a team of subject matter experts from across the Agency representing several disciplines including mechanisms, propulsion, environmental control and life support systems, spacesuits, active thermal control systems, and materials and processes.

The team has started their effort by reviewing lessons learned and best practices for valve design and hope to have a draft standard ready by the end of 2025.

Bearing Life Testing for Reaction Wheel Assemblies

The Mechanical Systems TDT just concluded a multiyear bearing life test on 40 motors, each containing a pair of all steel bearings of two different conformities or a pair of hybrid bearings containing silicon nitride balls.

The testing confirmed that hybrid bearings outperformed their steel counterparts, and bearings with higher conformity (54%) outperformed bearings with lower conformity (52%).

The team is disassembling and inspecting the bearings, and initial results have been surprising. The TDT was able to “recover” some of the bearings that failed during the life test and get them running as well as they did when testing began.

Some bearings survived over five billion revolutions and appeared like new when they were disassembled and inspected. These results will be published once analysis is complete.

X-57 Design Assessment

The Mechanical Systems TDT was asked by the Aeronautics Mission Directorate to assess the design of the electric cruise motors installed on X-57.

The team responded quickly to meet the Project’s schedule, making an onsite visit and attending numerous technical interchange meetings.

After careful review of the design, the TDT identified areas for higher-level consideration and risk assessment and attended follow-on reviews to provide additional comments and advice.

CLARREO Pathfinder Inner Radial Bearing Anomaly

The Climate Absolute Radiance and Refractivity Observatory (CLARREO) Pathfinder was designed to take highly accurate measurements of reflected solar radiation to better-understand Earth’s climate.

During payload functional testing, engineers detected a noise as the HySICS pointing system was rotated from its normal storage orientation.

Mechanical Systems TDT members reviewed the design and inspection reports after disassembly of the inner bearing unit, noticing contact marks on the bore of the inner ring and the shaft that confirmed that the inner ring of the bearing was moving on the shaft with respect to the outer ring.

Lubricant applied to this interface resolved the noise problem and allowed the project to maintain schedule without any additional costs.

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>>22236503

JPL Wheel Drive Actuator Extended Life Test Independent Review Team

A consequence of changes to its mission on Mars will require the Perseverance Rover to travel farther than originally planned.

Designed to drive 20 km, the rover will now need to drive ~91 km to rendezvous and support Mars sample tube transfer to the Sample Retrieval Lander.

The wheel drive actuators with integral brakes had only been life tested to 40 km, so a review was scheduled to discuss an extended life test.

The OCE Science Mission Directorate Chief Engineer assembled an independent review team (IRT) that included NESC Mechanical Systems TDT members.

This IRT issued findings and guidance that questioned details of the JPL assumptions and plan. Several important recommendations were made that improved the life test plan and led to the identification of brake software issues that were reducing brake life.

The life test has achieved 40 km of its 137 km goal and is ongoing. In addition, software updates were sent to the rover to improve brake life.

Orion Crew Module Hydrazine Valve

When an Orion crew module hydrazine valve failed to close, the production team asked the Mechanical Systems TDT for help.

A TDT member attended two meetings and then visited the valve manufacturer, where it was determined this valve was a scaled-down version of the 12-inch SLS prevalve that was the subject of a previous NESC assessment and shared similar issues.

The Orion Program requested NESC materials and mechanical systems support.

The Mechanical Systems TDT member then worked closely with a Lockheed Martin (LM) Fellow for Mechanisms to review all the valve vendor’s detailed drawings and assembly procedures and document any issues.

A follow-on meeting was held to brief both the LM and NASA Technical Fellows for Propulsion that a redesign and requalification was recommended.

These recommendations have now been elevated to the LM Vice President for Mission Success and the LM Chief Engineer for Orion.

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Volcanic Vistas of the Guatemala Highlands

Dec 26, 2024

Between 158,000 and 40,000 years ago, at least three explosive eruptions—including the first-documented super-eruption in Central America—reshaped the landscape of southwestern Guatemala.

The activity created a huge caldera that filled with water and formed Lago de Atitlán (Lake Atitlán).

The modern-day lake and volcanic landscape are visible in this image, acquired on January 17, 2024, with the OLI (Operational Land Imager) on Landsat 8.

The data were draped over a digital elevation model from NASA’s SRTM (Shuttle Radar Topography Mission) to emphasize the terrain.

Since the super-eruption about 85,000 years ago, three “new” volcanoes have formed along the southern side of the caldera rim.

Volcán Atitlán is the most active, youngest, and tallest. Its forested slopes are replaced by rocky terrain near the summit, especially on the southern side, deposited there during past eruptions.

Explosive eruptions at Atitlán have been documented since the 15th century, with the most recent known event occurring in 1853. Atitlán has been known to release volcanic gases between explosive events.

In contrast, nearby Volcán San Pedro and Volcán Tolimán lie dormant. Past activity at Tolimán, however, has left behind thick, hardened lava flows that form the irregular shape of Lago de Atitlán’s southern shoreline.

Elsewhere around the shore, the land is dotted with towns (gray) and agricultural land (light brown). Coffee, corn, beans, wheat, potatoes, sugar cane, and vegetables are commonly grown in the region.

Lago de Atitlán, which plunges to a maximum depth of about 340 meters (1,115 feet), is thought to be the deepest lake in Central America and appears a striking shade of blue.

Some areas, however, display a slight tinge of green. This color might be due to sediment washed into the lake carried by the rivers at the lake’s northern side.

Some of it might be due to blue-green algae, or cyanobacteria—single-celled organisms that can grow swiftly when nutrients like phosphorus and nitrogen are abundant in still water.

Blooms of these cyanobacteria now occur most years, with significant blooms appearing in Lago de Atitlán in October-November 2009 and August 2015.

The Lake Atitlán Forecasting System, however, indicated that the probability of a bloom on the day of this image was about 42 percent.

That’s low, according to Africa Flores-Anderson, a research physical scientist at NASA’s Marshall Space Flight Center.

Flores-Anderson, who worked with scientists from the University of Alabama in Huntsville, the joint USAID-NASA SERVIR program, and Lake Atitlán’s environmental authority to design the forecasting system, noted that blooms typically occur when probabilities reach 60 percent or higher.

In abundance, cyanobacteria can produce toxins and lead to dead zones. Modern societies may not be the only ones to have grappled with these issues.

Researchers found evidence in sediment cores that bloom events may have coincided with ancient Maya settlements around the lake 1,000 years ago.

https://earthobservatory.nasa.gov/images/153749/volcanic-vistas-of-the-guatemala-highlands

NASA's Parker Solar Probe: What Happens Next After Sun Flyby?

Dec 27, 2024 at 6:31 AM EST

NASA's Parker Solar Probe has once again made history, completing its closest-ever approach to the sun on December 24, 2024.

Hurtling through the solar corona at an astonishing 430,000 miles per hour and enduring temperatures nearing 1,800°F, the spacecraft ventured just 3.8 million miles from the solar surface.

After a tense period without contact, mission controllers at the Johns Hopkins Applied Physics Laboratory (APL) received a reassuring beacon tone late on December 26, confirming Parker's health and operational status.

As scientists await detailed data from the flyby, set to arrive on January 1, 2025, the probe's survival marks a critical milestone in science's quest to unravel the mysteries of our closest star.

Newsweek contacted NASA and Johns Hopkins APL via email for further comment.

NASA's Parker Solar Probe is a groundbreaking mission to dive into the sun's atmosphere, enduring extreme heat and radiation to give humanity its first-ever close-up sampling of a star's outer layers.

Launched in 2018, the spacecraft is equipped with cutting-edge thermal engineering and instruments to study the sun's magnetic fields, plasma, energetic particles and the solar wind.

The probe is named after the late Eugene N. Parker, a pioneer in solar physics who predicted the existence of the solar wind.

Designed to orbit the sun in highly elliptical loops, Parker uses Venus's gravity to accelerate and adjust its path for close encounters with the solar corona.

The Parker Solar Probe's discoveries have already transformed our understanding of the sun and its influence on Earth.

By answering long-standing questions—such as why the corona is hotter than the sun's surface and how solar wind accelerates—it provides critical data for forecasting space weather.

These insights protect satellites, power grids and astronauts from solar radiation.

"This is a monumental and audacious achievement," Helene Winters, Parker Solar Probe's project manager from Johns Hopkins APL, said in a statement.

"Parker Solar Probe is changing the field of heliophysics. After years of braving the heat and dust of the inner solar system, taking blasts of solar energy and radiation that no spacecraft has ever seen, Parker Solar Probe continues to thrive."

On December 24, 2024, Parker completed its closest-ever approach to the sun, passing just 3.8 million miles from its surface at a record-breaking speed of 430,000 miles per hour.

For context, if the distance between Earth and the sun was equivalent to the length of a football field, this closest approach would be around 4 yards from the end zone.

This latest flyby marks the spacecraft's 23rd close flyby and brings it deeper into the corona than ever before.

When data is returned, it will provide unprecedented details of the sun's behavior during its 11-year solar maximum.

NASA confirmed the probe's health on December 27, 2024, when a beacon tone signaled its successful navigation through the sun's outer atmosphere.

The mission team anticipates receiving detailed telemetry data on January 1, 2025, which will include observations about the solar wind, corona heating and the origins of high-energy solar particles.

Previous mission highlights include: sampling particles and magnetic fields in the sun's atmosphere, becoming the first spacecraft to "touch the sun" in 2021; capturing images of Venus' surface in visible wavelengths and studying its atmosphere;

observing dust thinning near the sun, confirming a theorized dust-free zone; and detecting magnetic reconnection events in the corona, linked to solar wind acceleration and corona heating.

Parker Solar Probe's journey isn't over just yet. It will continue its highly elliptical orbit, making two more close passes of the sun in March and June 2025.

After completing its primary mission in June 2025, the probe will remain in orbit to conduct additional observations until its onboard fuel runs out.

Without corrective thrusts, the solar wind will gradually push the spacecraft out of alignment with Earth, ending its ability to transmit data.

When its mission concludes, most of the probe will incinerate, leaving only its carbon heat shield to orbit the sun for potentially billions of years, until the very end of the solar system itself.

https://www.newsweek.com/nasa-parker-solar-probe-what-happens-next-sun-solar-flyby-2006481

https://science.nasa.gov/mission/parker-solar-probe/

https://x.com/NASASun/status/1872507988533039371

>>22236595

Quantum computers in space? Google’s CEO and Elon Musk are planning a revolution

December 27, 2024

The future of technology often feels like science fiction, and a recent conversation between Sundar Pichai, CEO of Google, and Elon Musk of SpaceX proved just that.

With Google unveiling its groundbreaking quantum chip Willow, a bold idea was floated—launching quantum computers into space.

This visionary concept could not only transform quantum computing but also push the boundaries of modern science as we know it.

Google’s Quantum Leap with Willow

Quantum computing has long promised to solve problems far beyond the reach of traditional computers, and Google’s Willow chip seems to be delivering on that vision.

In a recent demonstration, the chip completed a complex calculation in just five minutes—a task that would take classical supercomputers billions of years.

Google’s researchers describe this milestone as exceeding the known scales of physics, potentially unlocking groundbreaking possibilities in scientific research and technological development.

But despite its promise, the field of quantum computing faces significant challenges.

Quantum chips require isolation from electromagnetic interference and must operate at extremely low temperatures—conditions that are difficult to achieve on Earth.

These limitations hinder large-scale deployment and raise the question: Where can quantum computers thrive without such constraints?

Starship’s Role in the Quantum Future

Enter SpaceX’s Starship, the world’s most powerful spacecraft designed for ambitious missions such as lunar landings and the colonization of Mars.

With its ability to transport massive payloads, Starship could offer an unexpected solution: creating a quantum cluster in space.

During a conversation on X (formerly Twitter), Sundar Pichai proposed sending quantum computers into orbit to take advantage of the ideal conditions offered by space.

Free from Earth’s interference and with the ability to maintain stable, low temperatures, orbiting quantum systems could revolutionize how we process data and conduct research.

Elon Musk, ever the innovator, responded enthusiastically, suggesting that such a project could become a reality. Musk has long been an advocate for futuristic ideas, and this proposal aligns with his broader vision of leveraging space for human advancement.

A New Frontier for Energy and Innovation

The conversation didn’t stop at quantum computing. Musk also emphasized the untapped potential of solar energy, noting that humans currently use only about 5% of the sun’s available power.

He proposed installing large-scale solar farms in deserts to increase usage to 30%, and even hinted at future technologies like Dyson spheres, structures that could capture the sun’s energy on an unimaginable scale.

This fusion of ideas—quantum computing in space and maximizing solar energy—paints an ambitious picture of the future, where technological breakthroughs address some of humanity’s most pressing challenges.

The Promise of Quantum in Space

While the concept of deploying quantum computers in orbit is still in its infancy, the potential benefits are vast.

From advancing climate modeling to solving complex problems in medicine and materials science, space-based quantum systems could unlock capabilities far beyond what’s currently possible.

By combining Google’s expertise in quantum technology with SpaceX’s revolutionary Starship, Pichai and Musk are charting a course for a future where innovation knows no bounds. The next step? Turning this bold vision into reality.

One thing is clear: the collaboration between these two tech giants is a glimpse of what’s to come, and it’s nothing short of extraordinary.

https://glassalmanac.com/quantum-computers-in-space-googles-ceo-and-elon-musk-are-planning-a-revolution/