Connect with us

Published

2 months ago

on

The European Space Agency’s (ESA) recently launched Jupiter Icy Moons Explorer (JUICE) mission and NASA’s upcoming Europa Clipper mission could allow scientists to image landslides on the icy moons of Europa and Ganymede due to potential moonquakes on these small worlds. This comes after a recent study examined fault scarps on Europa and Ganymede orbiting Jupiter and Enceladus and Dione orbiting Saturn with the goal of drawing a connection between tectonic activity (quakes) and observed mass wasting (landslides) on these surfaces. The researchers “consider whether such smooth material can be generated by mass wasting triggered from local seismic shaking”, according to the study.

Active geological processes are not uncommon for moons orbiting Jupiter and Saturn. Their massive gravity induces tidal heating on these small bodies as the much larger planets stretch and compress the moons over the course of millions of years, including the present day.

While flat, smooth terrains have been imaged extensively on the ocean worlds of Europa, Ganymede, and Enceladus, the longstanding hypothesis from scientists is this terrain is the result of fluid from icy volcanoes, also known as cryovolcanism, which has been observed on a number of planetary bodies throughout the solar system. However, given these moons are unspeakably cold and inhospitable for life, this hypothesis was left unanswered until now.

jpegPIA25498 1
NASA’s Galileo spacecraft snapped this close-up image of Europa’s surface in the 1990s displaying fault scarps, smooth slopes, and nearby rubble piles that could be indicative of landslides on the small moon. This image was cropped, rotated, and zoomed in from a much larger image. (Credit: NASA/JPL-Caltech)

For the study, the researchers measured steep ridges on the four moons that are hypothesized to be tectonic faults scarps. These scarps are the result of the surface splitting along a fault line and one side of the split dropping beneath the other. If this sounds familiar, these are very common on Earth. The team then input these measurements into seismic models and determined an inferred magnitude range between 4.0 to 7.9 for Europa, Ganymede, and Enceladus. While scarps on Dione were measured, quakes and landslides on the moon were not modeled due to a lack of “structural models in Planetprofile and the seismogram database”, according to the study.

dione super close ISS 129DI DIONEPTG001 CAPS N1649311515 1
NASA’s Cassini spacecraft snapped this image of potential faults and scarps on Dione’s surface from ~500-km away on April 7, 2010. (Credit: NASA/JPL-Caltech/Space Science Institute)

“We found the surface shaking from moonquakes would be enough to cause surface material to rush downhill in landslides. We’ve estimated the size of moonquakes and how big the landslides could be,” said Mackenzie Mills, who is a PhD student in the Lunar and Planetary Laboratory at the University of Arizona, and lead author of the study. Mills carried out the research over the course of several summer internships at NASA’s Jet Propulsion Laboratory (JPL). “This helps us understand how landslides might be shaping moon surfaces over time.”

The researchers mention that data from the JUICE mission and the Europa Clipper mission “will advance both regional and local understanding of topography on these bodies”, meaning these spacecraft could both image and gather data on potentially active surface tectonics and mass wasting during their respective missions observing these moons.

ESA’s JUICE successfully
Did you miss our previous article…
https://mansbrand.com/the-milky-way-has-trapped-the-large-magellanic-cloud-with-its-gravity-what-comes-next/

Total
0
Shares
Share 0
Tweet 0
Pin it 0
Share 0
Related Topics:
Continue Reading

Frontier Adventure

Transporter-8 Mission

Published

8 hours ago

on

June 10, 2023

By

hqdefault 10

hqdefault 11

SpaceX is targeting Monday, June 12 for Falcon 9’s launch of the Transporter-8 mission to low-Earth orbit from Space Launch Complex 4E (SLC-4E) at Vandenberg Space Force Base in California. The 57-minute launch window opens at 2:19 p.m. PT (21:19 UTC). If needed, there is a backup opportunity Tuesday, June 13 with the same window.

The first stage booster supporting this mission previously launched NROL-87, NROL-85, SARah-1, SWOT, and four Starlink missions. Following stage separation, Falcon 9 will land on Landing Zone 4 (LZ-4) at Vandenberg Space Force Base.

Transporter-8 is SpaceX’s eighth dedicated smallsat rideshare mission. There will be 72 payloads on this flight, including CubeSats, MicroSats, a re-entry capsule, and orbital transfer vehicles carrying spacecraft to be deployed at a later time.

A live webcast of this mission will begin about 15 minutes prior to liftoff.

Did you miss our previous article…
https://mansbrand.com/triggered-star-birth-in-the-nessie-nebula/

Continue Reading

Frontier Adventure

Triggered Star Birth in the Nessie Nebula

Published

2 days ago

on

June 9, 2023

By

Webb s instruments showcase the Pillars of Creation NIRCam for slider 1024x964 1

Star formation is one of the oldest processes in the Universe. In the Milky Way and most other galaxies, it unfolds in cold, dark creches of gas and dust. Astronomers study sites of star formation to understand the process. Even though they know much about it, some aspects remain mysterious. That’s particularly true for the “Nessie Nebula” in the constellation Vulpecula. An international team led by astronomer James Jackson studies the nebula and its embedded star-birth regions. They found that it experienced a domino effect called “triggered star formation.”

“So, one of the interesting and open questions remaining in the field of star formation is, what happens when a star forms and ejects energy into the surrounding medium?” he said. “Does it make new stars, or does it prevent the formation of new stars?”

To answer those questions, Jackson and an international team of observers peered deep into the Nessie Nebula. It’s a so-called “Infrared Dark Cloud” (IRDC) with the official catalog name Lynds 772. Jackson named it the Loch Ness Monster Nebula a few years back. That’s because it resembles a spindly version of the famous and elusive Scottish lake monster. What the team found reveals that triggered star formation actually does take place under special circumstances in this nebula.

Putting the Nessie Nebula in Perspective

In 2013, Dr. Alyssa Goodman of Harvard Center for Astrophysics called the Nessie Nebula one of the “bones” of the Milky Way. That’s because it’s one of many webs of dusty filaments threaded through the galaxy. “It’s possible that the Nessie bone lies within a spiral arm, or that it is part of a web connecting bolder spiral features,” she said, noting that it probably spans at least 80 parsecs long and about a half-parsec wide.

As a galactic “bone”, it’s a prime place to look for triggered star formation. Nessie has a density of about 600 solar masses per parsec across its entire length. It’s also cold, with an average temperature of about 10K. There are many such cold clouds in the Milky Way, notably places like the famous Pillars of Creation or regions in the Carina Nebula.

The Pillars of Creation is another region of cold, dark gas similar to the Nessie Nebula where young stars are forming. Image Credit: NASA/ESA/CSA
The Pillars of Creation is similar to the Nessie Nebula where young stars are forming. Image Credit: NASA/ESA/CSA

A star gets started when gravity pushes the material in the cloud together to form a hot core. Temperatures and pressures rise, and eventually, a star is born. The Nessie Nebula is actually dense enough to form many very high-mass stars, according to Jackson. “By high mass, I mean a star that’s about 8 times the mass of the Sun, or more,” he said. “They have so much more energy than the Sun, and they inject this energy into the surrounding material, and they form these H II bubbles that ionize the gas around them.”

Essentially, those H II bubbles form as stellar winds from the hot young protostars push into surrounding space and photoionize (or heat) the gas there. As they expand, they stir up material around them. That creates a lot of energy. “The question I’m trying to answer is, does this energetic feedback trigger or hinder the formation of other new stars?” said Jackson.

The Domino Effect in the Nessie Nebula

The scenario for triggered star formation requires an almost perfect set of circumstances, starting with the cold dense nebula. Jackson explained that once a star (or group of stars) forms, its H II bubble triggers the birth process of the next star. That process repeats, almost like a domino effect.

So, does this triggered star formation really happen? Jackson pointed out two different scenarios. “If bubbles are just dispersing the gas, then that gas is gone and no stars can form,” he said. “On the other hand, if you have a clump of gas that’s almost ready to make a star, but not quite, can you hit it with an expanding shell and compress it? It could push it over the edge and gravity can take over. Some people say you make new stars and some say you don’t.”

To find out, the team looked at Nessie with the infrared-sensitive SOFIA flying observatory. It allowed them to peer through the clouds of gas and dust at the central region of the nebula. They coupled their observations with radio data from the Australia Telescope Compact Array and the Mopra radio dish. They zeroed in on its most luminous young stellar object, called AGAL337.916-00.477. This high-mass stellar object is part of a cloud in the nebula that has several other high-mass young stellar objects and so-called “dust cores” where the process of star

Continue Reading

Frontier Adventure

New Detailed Images of the Sun from the World’s Most Powerful Ground-Based Solar Telescope

Published

2 days ago

on

June 9, 2023

By

atst.ics.vbiBlue.dc .vcc .xfer .107703 compressed8 600

Our Sun continues to demonstrate its awesome power in a breathtaking collection of recent images taken by the U.S. National Science Foundation’s (NSF’s) Daniel Inouye Solar Telescope, aka Inouye Solar Telescope, which is the world’s largest and most powerful ground-based solar telescope. These images, taken by one of Inouye’s first-generation instruments, the Visible-Broadband Imager (VBI), show our Sun in incredible, up-close detail.

“These images preview the exciting science underway at the Inouye Solar Telescope,” Dr. Alexandra Tritschler, who is a National Solar Observatory Senior Scientist, tells Universe Today. “These images are a small fraction of the data obtained from the first Cycle. They exemplify the many and much broader science objectives and the much more powerful spectroscopy and spectropolarimetry data that now goes along with the images, none of which was available in 2020 when the Inouye Solar Telescope released its first-light images.”

The solar features in Inouye’s images include sunspots which reside in the Sun’s photosphere. These are the dark spots on the Sun’s “surface” and one of the Sun’s most well-known features, often reaching sizes that equal, or even dwarf, the size of the Earth. It is their dark appearance that can be deceiving, however, as sunspots are responsible for solar flares and coronal mass ejections that produce solar storms, which is a type of space weather.

atst.ics.vbiBlue.dc .vcc .xfer .107703 compressed8 600 1
Image of a sunspot taken by the Inouye Solar Telescope. While they have a dark appearance, sunspots are responsible for solar flares and coronal mass ejections that produce solar storms. Sunspots often reach sizes that equal, or even dwarf, the size of the Earth. (Credit: National Science Foundation (NSF)/Association of Universities for Research in Astronomy, Inc. (AURA)/National Solar Observatory (NSO))
atst.ics.vbiBlue.dc .vcc .xfer .107796.391848 1 compressed8 600
Image of a sunspot with a light bridge, which is hypothesized to be the beginning stages of a degrading sunspot. (Credit: NSF/AURA/NSO)

Other features from the Inouye images include convection cells, which also reside in the Sun’s photosphere, and consist of upward- and downward-flowing plasma, known as granules or “bubbles”. The last feature in the Inouye images are fibrils, which exist in the Sun’s chromosphere and are produced from the magnetic field interactions within the Sun.

atst.ics.vbiBlue.dc .vcc .xfer .89208.100846 1 1920x1024 1000
Image of solar granules or “bubbles”, intergranular lanes, and magnetic elements in the quiet regions of the Sun. In these features, solar plasma rises in the
Did you miss our previous article…
https://mansbrand.com/review-mountain-hardwear-kor-airshell-hoody/

Continue Reading

Trending