Members Can Post Anonymously On This Site
NASA’s Webb Findings Support Long-Proposed Process of Planet Formation
-
Similar Topics
-
By European Space Agency
For the first time, the NASA/ESA/CSA James Webb Space Telescope has detected and ‘weighed’ a galaxy, in the early Universe, that has a mass that is similar to what our Milky Way galaxy’s mass might have been at the same stage of development. Found at around 600 million years after the Big Bang, this lightweight galaxy, nicknamed the Firefly Sparkle, is gleaming with star clusters – 10 in total – that researchers examined in great detail. Other galaxies Webb has detected at this period in the history of the Universe are significantly more massive.
View the full article
-
By NASA
Artist’s concept depicts new research that has expanded our understanding of exoplanet WASP-69 b’s “tail.” NASA/JPL-Caltech/R. Hurt (IPAC) The Planet
WASP-69 b
The Discovery
The exoplanet WASP-69 b has a “tail,” leaving a trail of gas in its wake.
Key Takeaway
WASP-69 b is slowly losing its atmosphere as light hydrogen and helium particles in the planet’s outer atmosphere escape the planet over time. But those gas particles don’t escape evenly around the planet, instead they are swept into a tail of gas by the stellar wind coming from the planet’s star.
Details
Hot Jupiters like WASP-69 b are super-hot gas giants orbiting their host stars closely. When radiation coming from a star heats up a planet’s outer atmosphere, the planet can experience photoevaporation, a process in which lightweight gases like hydrogen and helium are heated by this radiation and launched outward into space. Essentially, WASP-69 b’s star strips gas from the planet’s outer atmosphere over time.
What’s more, something called the stellar wind can shape this escaping gas into an exoplanetary tail.
The stellar wind is a continuous stream of charged particles that flow outwards into space from a star’s outer atmosphere, or corona. On Earth, the Sun’s stellar wind interacts with our planet’s magnetic field which can create beautiful auroras like the Northern Lights.
On WASP-69 b, the stellar wind coming from its host star actually shapes the gas escaping from the planet’s outer atmosphere. So, instead of gas just escaping evenly around the planet, “strong stellar winds can sculpt that outflow in tails that trail behind the planet,” said lead author Dakotah Tyler, an astrophysicist at the University of California, Los Angeles, likening this gaseous tail to a comet’s tail.
Because this tail is created by the stellar wind, however, that means it’s subject to change.
“If the stellar wind were to taper down, then you could imagine that the planet is still losing some of its atmosphere, but it just isn’t getting shaped into the tail,” Tyler said, adding that, without the stellar wind, that gas escaping on all sides of the planet would be spherical and symmetrical. “But if you crank up the stellar wind, that atmosphere then gets sculpted into a tail.”
Tyler likened the process to a windsock blowing in the breeze, with the sock forming a more structured shape when the wind picks up and it fills with air.
The tail that Tyler and his research team observed on WASP-69 b extended more than 7.5 times the radius of the planet, or over 350,000 miles. But it’s possible that the tail is even longer. The team had to end observations with the telescope before the tail’s signal disappeared, so this measurement is a lower limit on the tail’s true length at the time.
However, keep in mind that because the tail is influenced by the stellar wind, changes in the stellar wind could change the tail’s size and shape over time. Additionally changes in the stellar wind influence the tail’s size and shape, but since the tail is visible when illuminated by starlight, changes in stellar activity can also affect tail observations.
Exoplanet tails are still a bit mysterious, especially because they are subject to change. The study of exoplanet tails could help scientists to better understand how these tails form as well as the ever-changing relationship between the stellar and planetary atmospheres. Additionally, because these exoplanetary tails are shaped by stellar activity, they could serve as indicators of stellar behavior over time. This could be helpful for scientists as they seek to learn more about the stellar winds of stars other than the star we know the most about, our very own Sun.
Fun Facts
WASP-69 b is losing a lot of gas — about 200,000 tons per second. But it’s losing this gaseous atmosphere very slowly — so slowly in fact that there is no danger of the planet being totally stripped or disappearing. In general, every billion years, the planet is losing an amount of material that equals the mass of planet Earth.
The solar system that WASP-69 b inhabits is about 7 billion years old, so even though the rate of atmosphere loss will vary over time, you might estimate that this planet has lost the equivalent of seven Earths (in mass) of gas over that period.
The Discoverers
A team of scientists led by Dakotah Tyler of the University of California, Los Angeles published a paper in January, 2024 on their discovery, “WASP-69b’s Escaping Envelope Is Confined to a Tail Extending at Least 7 Rp,” in the journal, “The Astrophysical Journal.” The observations described in this paper were made by Keck/NIRSPEC (NIRSPEC is a spectrograph designed for Keck II).
View the full article
-
By NASA
Through the Artemis campaign, NASA will land the next American astronauts and first international astronaut on the South Pole region of the Moon. On Thursday, NASA announced the latest updates to its lunar exploration plans.
Experts discussed results of NASA’s investigation into its Orion spacecraft heat shield after it experienced an unexpected loss of charred material during re-entry of the Artemis I uncrewed test flight. For the Artemis II crewed test flight, engineers will continue to prepare Orion with the heat shield already attached to the capsule. The agency also announced it is now targeting April 2026 for Artemis II and mid-2027 for Artemis III. The updated mission timelines also reflect time to address the Orion environmental control and life support systems.
“The Artemis campaign is the most daring, technically challenging, collaborative, international endeavor humanity has ever set out to do,” said NASA Administrator Bill Nelson. “We have made significant progress on the Artemis campaign over the past four years, and I’m proud of the work our teams have done to prepare us for this next step forward in exploration as we look to learn more about Orion’s life support systems to sustain crew operations during Artemis II. We need to get this next test flight right. That’s how the Artemis campaign succeeds.”
The agency’s decision comes after an extensive investigation of an Artemis I heat shield issue showed the Artemis II heat shield can keep the crew safe during the planned mission with changes to Orion’s trajectory as it enters Earth’s atmosphere and slows from nearly 25,000 mph to about 325 mph before its parachutes unfurl for safe splashdown in the Pacific Ocean.
“Throughout our process to investigate the heat shield phenomenon and determine a forward path, we’ve stayed true to NASA’s core values; safety and data-driven analysis remained at the forefront,” said Catherine Koerner, associate administrator, Exploration Systems Development Mission Directorate at NASA Headquarters in Washington. “The updates to our mission plans are a positive step toward ensuring we can safely accomplish our objectives at the Moon and develop the technologies and capabilities needed for crewed Mars missions.”
NASA will continue stacking its SLS (Space Launch System) rocket elements, which began in November, and prepare it for integration with Orion for Artemis II.
Throughout the fall months, NASA, along with an independent review team, established the technical cause of an issue seen after the uncrewed Artemis I test flight in which charred material on the heat shield wore away differently than expected. Extensive analysis, including from more than 100 tests at unique facilities across the country, determined the heat shield on Artemis I did not allow for enough of the gases generated inside a material called Avcoat to escape, which caused some of the material to crack and break off. Avcoat is designed to wear away as it heats up and is a key material in the thermal protection system that guards Orion and its crew from the nearly 5,000 degrees Fahrenheit of temperatures that are generated when Orion returns from the Moon through Earth’s atmosphere. Although a crew was not inside Orion during Artemis I, data shows the temperature inside Orion remained comfortable and safe had crew been aboard.
Engineers already are assembling and integrating the Orion spacecraft for Artemis III based on lessons learned from Artemis I and implementing enhancements to how heat shields for crewed returns from lunar landing missions are manufactured to achieve uniformity and consistent permeability. The skip entry is needed for return from speeds expected for lunar landing missions.
“Victor, Christina, Jeremy, and I have been following every aspect of this decision and we are thankful for the openness of NASA to weigh all options and make decisions in the best interest of human spaceflight. We are excited to fly Artemis II and continue paving the way for sustained human exploration of the Moon and Mars,” said Reid Wiseman, NASA astronaut and Artemis II commander. “We were at the agency’s Kennedy Space Center in Florida recently and put eyes on our SLS rocket boosters, the core stage, and the Orion spacecraft. It is inspiring to see the scale of this effort, to meet the people working on this machine, and we can’t wait to fly it to the Moon.”
Wiseman, along with NASA astronauts Victor Glover and Christina Koch and CSA (Canadian Space Agency) astronaut Jeremy Hansen, will fly aboard the 10-day Artemis II test flight around the Moon and back. The flight will provide valuable data about Orion systems needed to support crew on their journey to deep space and bring them safely home, including air revitalization in the cabin, manual flying capabilities, and how humans interact with other hardware and software in the spacecraft.
With Artemis, NASA will explore more of the Moon than ever before, learn how to live and work farther away from home, and prepare for future human exploration of the Red Planet. NASA’s SLS, exploration ground systems, and Orion spacecraft, along with the human landing system, next-generation spacesuits, Gateway lunar space station, and future rovers are NASA’s foundation for deep space exploration.
For more information about Artemis, visit:
https://www.nasa.gov/artemis
-end-
Meira Bernstein / Rachel Kraft
Headquarters, Washington
202-358-1600
meira.b.bernstein@nasa.gov / rachel.h.kraft@nasa.gov
Share
Details
Last Updated Dec 05, 2024 LocationNASA Headquarters Related Terms
Missions Artemis Artemis 2 Exploration Systems Development Mission Directorate NASA Directorates View the full article
-
By European Space Agency
Using the NASA/ESA/CSA James Webb Space Telescope, an international team of astronomers have found new galaxies in the Spiderweb protocluster. Their characteristics reveal that new galaxies are forming in these large cosmic cities, with the finding that gravitational interactions in these dense regions are not as important as previously thought.
View the full article
-
By Space Force
Acknowledging the U.S. Space Force’s mission, structure and unique demands, Space Operations Command leadership developed the Guardian and Airmen Development Program to foster a new generation of leaders.
View the full article
-
-
Check out these Videos
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.