NASA Astronomy Picture of the Day

May 16, 2024

Aurora Georgia

A familiar sight from Georgia, USA, the Moon sets near the western horizon in this rural night skyscape. Captured on May 10 before local midnight, the image overexposes the Moon's bright waning crescent at left in the frame. A long irrigation rig stretches across farmland about 15 miles north of the city of Bainbridge. Shimmering curtains of aurora shine across the starry sky, definitely an unfamiliar sight for southern Georgia nights. Last weekend, extreme geomagnetic storms triggered by the recent intense activity from solar active region AR 3664 brought epic displays of aurora, usually seen closer to the poles, to southern Georgia and even lower latitudes on planet Earth. As solar activity ramps up, more storms are possible.

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

https://www.nasa.gov/missions/juno/nasas-juno-provides-high-definition-views-of-europas-icy-shell/

NASA’s Juno Provides High-Definition Views of Europa’s Icy Shell

MAY 15, 2024

Images from the JunoCam visible-light camera aboard NASA’s Juno spacecraft supports the theory that the icy crust at the north and south poles of Jupiter’s moon Europa is not where it used to be. Another high-resolution picture of the icy moon, by the spacecraft’s Stellar Reference Unit (SRU), reveals signs of possible plume activity and an area of ice shell disruption where brine may have recently bubbled to the surface.

The JunoCam results recently appeared in the Planetary Science Journal and the SRU results in the journal JGR Planets.

On Sept. 29, 2022, Juno made its closest flyby of Europa, coming within 220 miles (355 kilometers) of the moon’s frozen surface. The four pictures taken by JunoCam and one by the SRU are the first high-resolution images of Europa since Galileo’s last flyby in 2000.

Juno’s ground track over Europa allowed imaging near the moon’s equator. When analyzing the data, the JunoCam team found that along with the expected ice blocks, walls, scarps, ridges, and troughs, the camera also captured irregularly distributed steep-walled depressions 12 to 31 miles (20 to 50 kilometers) wide. They resemble large ovoid pits previously found in imagery from other locations of Europa.

A giant ocean is thought to reside below Europa’s icy exterior, and these surface features have been associated with “true polar wander,” a theory that Europa’s outer ice shell is essentially free-floating and moves.

“True polar wander occurs if Europa’s icy shell is decoupled from its rocky interior, resulting in high stress levels on the shell, which lead to predictable fracture patterns,” said Candy Hansen, a Juno co-investigator who leads planning for JunoCam at the Planetary Science Institute in Tucson, Arizona. “This is the first time that these fracture patterns have been mapped in the southern hemisphere, suggesting that true polar wander’s effect on Europa’s surface geology is more extensive than previously identified.”

The high-resolution JunoCam imagery has also been used to reclassify a formerly prominent surface feature from the Europa map.

“Crater Gwern is no more,” said Hansen. “What was once thought to be a 13-mile-wide impact crater — one of Europa’s few documented impact craters — Gwern was revealed in JunoCam data to be a set of intersecting ridges that created an oval shadow.”

Although all five Europa images from Juno are high-resolution, the image from the spacecraft’s black-and-white SRU offers the most detail. Designed to detect dim stars for navigation purposes, the SRU is sensitive to low light. To avoid over-illumination in the image, the team used the camera to snap the nightside of Europa while it was lit only by sunlight scattered off Jupiter (a phenomenon called “Jupiter-shine”).

This innovative approach to imaging allowed complex surface features to stand out, revealing intricate networks of cross-cutting ridges and dark stains from potential plumes of water vapor. One intriguing feature, which covers an area 23 miles by 42 miles (37 kilometers by 67 kilometers), was nicknamed by the team “the Platypus” because of its shape.

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Characterized by chaotic terrain with hummocks, prominent ridges, and dark reddish-brown material, the Platypus is the youngest feature in its neighborhood. Its northern “torso” and southern “bill” — connected by a fractured “neck” formation — interrupt the surrounding terrain with a lumpy matrix material containing numerous ice blocks that are 0.6 to 4.3 miles (1 to 7 kilometers) wide. Ridge formations collapse into the feature at the edges of the Platypus.

For the Juno team, these formations support the idea that Europa’s ice shell may give way in locations where pockets of briny water from the subsurface ocean are present beneath the surface.

About 31 miles (50 kilometers) north of the Platypus is a set of double ridges flanked by dark stains similar to features found elsewhere on Europa that scientists have hypothesized to be cryovolcanic plume deposits.

“These features hint at present-day surface activity and the presence of subsurface liquid water on Europa,” said Heidi Becker, lead co-investigator for the SRU at NASA’s Jet Propulsion Laboratory in Southern California, which also manages the mission. “The SRU’s image is a high-quality baseline for specific places NASA’s Europa Clipper mission and ESA’s (European Space Agency’s) Juice missions can target to search for signs of change and brine.”

“These features hint at present-day surface activity and the presence of subsurface liquid water on Europa,” said Heidi Becker, lead co-investigator for the SRU at NASA’s Jet Propulsion Laboratory in Southern California, which also manages the mission. “The SRU’s image is a high-quality baseline for specific places NASA’s Europa Clipper mission and ESA’s (European Space Agency’s) Juice missions can target to search for signs of change and brine.”

Europa Clipper’s focus is on Europa — including investigating whether the icy moon could have conditions suitable for life. It is scheduled to launch on the fall of 2024 and arrive at Jupiter in 2030. Juice (Jupiter Icy Moons Explorer) launched on April 14, 2023. The ESA mission will reach Jupiter in July 2031 to study many targets (Jupiter’s three large icy moons, as well as fiery Io and smaller moons, along with the planet’s atmosphere, magnetosphere, and rings) with a special focus on Ganymede.

Juno executed its 61st close flyby of Jupiter on May 12. Its 62nd flyby of the gas giant, scheduled for June 13, includes an Io flyby at an altitude of about 18,200 miles (29,300 kilometers).

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Korea's version of NASA to launch on May 27

May 16, 2024

A banner announcing the opening of the Korea AeroSpace Administration (KASA), set to open on May 27, is shown hanging in Changwon, South Gyeongsang, on Thursday.

KASA was based off of NASA from the United States. The Yoon Suk Yeol government aims to develop over 2,000 aerospace companies and generate 500,000 jobs through the establishment of the agency, with the goal of becoming one of the top five space powers globally by 2045. Seoul National University's aerospace engineering professor Yoon Young-bin was appointed by Yoon as KASA's inaugural chief on April 24.

https://koreajoongangdaily.joins.com/news/2024-05-16/business/industry/Koreas-version-of-NASA-to-launch-on-May-27/2048498

FAA reauthorization bill includes short-term learning period extension

May 15, 2024

WASHINGTON — A reauthorization bill for the Federal Aviation Administration passed by Congress will extend current restrictions on the agency’s ability to regulate commercial spaceflight occupant safety through the end of the year.

The House approved H.R. 3935, the bill reauthorizing the agency for five years, on a 387 to 26 vote May 15. The Senate approved the bill on an 88 to 4 vote on May 9.

The bill primarily covers the FAA’s aviation operations, but does include a few provisions related to spaceflight. Key among them is another extension of the “learning period” that restricts the FAA’s ability to enact regulations for the safety of occupants of commercial spacecraft. That learning period, which was to expire this month, is now extended until Jan. 1, 2025.

The learning period was enacted in a commercial space bill in 2004 and originally set to expire in eight years. The intent of the learning period was to give industry time to build up flight experience that would inform future regulations. The slow development of commercial human spaceflight vehicles, though, led to several extensions of the learning period.

The relatively short extension included in the FAA reauthorization bill means additional legislation will be needed this year for the longer extension that many in industry desire. The House Science Committee approved a commercial space bill last November that would extend the learning period to October 2031 while a Senate bill introduced in March would provide a five-year extension.

The FAA reauthorization bill includes a few other provisions that tangentially involve commercial spaceflight. It directs the Government Accountability Office to study the effect of airspace congestion on commercial aviation, with “commercial space launch and reentry activities” among the factors to include in the study.

Another section authorizes the FAA to spend $10 million annually from 2025 through 2028 on technologies to better integrate space launch and reentry data into air traffic management systems. Those include systems to provide such information directly to displays used by air traffic controllers as well as systems intended for more dynamic closing and reopening of airspace based on the status of launches and reentries.

The FAA has been working on such systems, including a long-running project called the Space Data Integrator, a tool to automate the distribution of data from launches and reentries to air traffic controllers. An FAA official said at an advisory committee meeting a year ago that full integration of launch and reentry data into air traffic management systems wouldn’t be completed until 2028 because of budget constraints.

https://spacenews.com/faa-reauthorization-bill-includes-short-term-learning-period-extension/

https://www.congress.gov/bill/118th-congress/house-bill/3935/text