Science

Satellite Images Can Help Predict When Underwater Volcanos are About to Erupt – Universe Today

Published

12 months ago

July 10, 2021

Harry Miller

Predicting volcanic eruptions is notoriously tricky. In large part this is because volcanos are unique, each with their own quirks and personalities: the lessons learned from studying one volcano may not apply directly to another. Luckily, researchers are getting better at finding warning signs that they can apply broadly. Some of the most well-known are heightened seismic activity, rising temperatures, expanding magma pools, and the release of gases. New research using satellite imagery now offers a new warning sign for underwater volcanos: a change in the color of the ocean.

The idea is simple: it has long been known that as underwater volcanos prepare to erupt, the gases and compounds they release affect the composition of the surrounding seawater. Iron-rich water looks yellowish or brown, for example, while aluminum and silicon turn the water white. The challenge has always been in systematically applying this information to make useful predictions. Measuring these color changes accurately isn’t easy.

Yuji Sakuno, associate professor at Hiroshima University, has been working on this problem. As an expert in remote sensing, his key tool in this endeavor is the Japanese Space Agency (JAXA)’s Global Change Observation Mission – Climate (GCOM-C) satellite. GCOM-C observes the ocean every 2-3 days at 250-meter resolution, giving Sakuno reliable data about changes in water color over time.

By combining GCOM-C imagery with eruption information from Himawari-8 (a geostationary weather satellite) Sakuno was able to note changes in sea water colour about a month prior to volcanic activity on Nishinoshima Island.

This photo shows a sample of the (Fe + Al)/Si distribution as a volcanic activity index from May 16 to June 25 around Nishinoshima Island: (a) May 16-23, 2020, (b) May 24-31, 2020, (c) June 1-8, 2020, (d) June 9-16, 2020, (e) June 17-24, 2020, (f) June 25-July 2, 2020. It is mapped by applying the equation ((Fe+Al)/Si)=45.4(x)-13.3 to the SGLI (Second Generation Global Imager – an instrument onboard GCOM-C) data. From this, it can be seen that during this period, the distribution on the northeastern part of the island rises, and then the discoloration gradually progresses to the sea area around the island, before it disappears. Nishinoshima Island is located approximately 1,000 km south of Tokyo, Japan. The original data used for this product have been supplied by JAXA’s JASMES (JAXA Satellite Monitoring for Environmental Studies). Credit: JAXA/Yuji Sakuno.

One of the breakthroughs that made this possible involved finding a way to measure color accurately, despite the way that sunlight can distort and play tricks with apparent water color. Sakuno looked to other areas of research to find a solution: previous work done on hot spring water provided the tools needed to counteract the Sun’s distortions.

Sakuno has big plans for this technique: “In the future,” he said, “I would like to establish a system that can predict volcanic eruptions with higher accuracy in cooperation with the Japan Aerospace Exploration Agency (JAXA), the Maritime Security Agency, which is monitoring submarine volcanos, and related research.”

This image illustrates the colorimetric data of discolored seawater in four directions (north, east, south, and west) around Nishinoshima Island in 2020. The study investigated the color characteristics of the water to validate if the data obtained by SGLI accurately captures the actual conditions of the discolored seawater. It detected significant fluctuations in the distribution of chemicals in Nishinoshima Island, estimated from SGLI data, about one month even before the volcano became active. Credit: Yuji Sakuno.

This research also underlines the value of Earth observation satellites. The vast majority of spacecraft launched into orbit are used not to study the Universe, but rather are turned to look back at Earth. Space missions like GCOM-C are designed to improve life here at home. Whether by enabling communications and GPS, or helping us understand and track climate change, or keeping us safe from dramatic events like volcanic eruptions, the world’s space infrastructure has very real value to all of us ground-bound Earthlings.

Learn more:

“To predict underwater volcano eruptions, scientist looks at images from space.” Hiroshima University

Sakuno, Y. “Trial of Chemical Composition Estimation Related to Submarine Volcano Activity Using Discolored Seawater Color Data Obtained from GCOM-C SGLI. A Case Study of Nishinoshima Island, Japan, in 2020.” Water.

Featured Image Credit: NOAA/National Science Foundation: Superheated molten lava from West Mata submarine volcano.

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NASA discovers double crater on the moon – CTV News

Published

8 hours ago

June 28, 2022

Harry Miller

The moon has a new double crater after a rocket body collided with its surface on March 4.

New images shared by NASA’s Lunar Reconnaissance Orbiter, which has been circling the moon since 2009, have revealed the location of the unusual crater.

The impact created two craters that overlap, an eastern crater measuring 59 feet (18 metres) across and a western crater spanning 52.5 feet (16 metres). Together, they create a depression that is roughly 91.8 feet (28 metres) wide in the longest dimension.

Although astronomers expected the impact after discovering that the rocket part was on track to collide with the moon, the double crater it created was a surprise.

Typically, spent rockets have the most mass at the motor end because the rest of the rocket is largely just an empty fuel tank. But the double crater suggests that this object had large masses at both ends when it hit the moon.

The exact origin of the rocket body, a piece of space junk that had been careening around for years, is unclear, so the double crater could help astronomers determine what it was.

The moon lacks a protective atmosphere, so it’s littered with craters created when objects like asteroids regularly slam into the surface.

This was the first time a piece of space junk unintentionally hit the lunar surface that experts know of. But craters have resulted from spacecraft being deliberately crashed into the moon.

For example, four large moon craters attributed to the Apollo 13, 14, 15 and 17 missions are all much larger than each of the overlapping craters created during the March 4 impact. However, the maximum width of the new double crater is similar to the Apollo craters.

UNCLEAR ORIGIN

Bill Gray, an independent researcher focused on orbital dynamics and the developer of astronomical software, was first to spot the trajectory of the rocket booster.

Gray had initially identified it as the SpaceX Falcon rocket stage that launched the US Deep Space Climate Observatory, or DSCOVR, in 2015 but later said he’d gotten that wrong and it was likely from a 2014 Chinese lunar mission — an assessment NASA agreed with.

However, China’s Ministry of Foreign Affairs denied the booster was from its Chang’e-5 moon mission, saying that the rocket in question burned up on reentry to Earth’s atmosphere.

No agencies systematically track space debris so far away from Earth, and the confusion over the origin of the rocket stage has underscored the need for official agencies to monitor deep-space junk more closely, rather than relying on the limited resources of private individuals and academics.

However, experts say that the bigger challenge is the space debris in low-Earth orbit, an area where it can collide with functioning satellites, create more junk and threaten human life on crewed spacecraft.

There are at least 26,000 pieces of space junk orbiting Earth that are the size of a softball or larger and could destroy a satellite on impact; over 500,000 objects the size of a marble — big enough to cause damage to spacecraft or satellites; and over 100 million pieces the size of a grain of salt, tiny debris that could nonetheless puncture a spacesuit, according to a NASA report issued last year.

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7 Amazing Dark Sky National Parks – AARP

Published

9 hours ago

June 28, 2022

Harry Miller

James Ronan/Getty Images/Steve Burns

Great Basin, Arches, and Voyageurs National Park

Can’t afford to join a commercial space mission offered by Jeff Bezos or Richard Branson? Consider the next best thing: seeing a starry, starry night in a sea of darkness, unimpeded by artificial light, at one of the International Dark Sky Parks in the U.S. It’s a rare treat, since light pollution prevents nearly 80 percent of Americans from seeing the Milky Way from their homes.

The International Dark-Sky Association (IDSA) has certified 14 of the nation’s 63 national parks as dark sky destinations. So visitors can take full advantage of such visibility, many of them offer specialized after-dark programs, from astronomy festivals and ranger-led full-moon walks to star parties and astrophotography workshops. If you prefer to stargaze on your own at a park, the National Park Service recommends bringing a pair of 7-by-50 binoculars, a red flashlight, which enhances night vision, and a star chart, which shows the arrangement of stars in the sky.

Here are seven of the IDSA-certified parks where you can appreciate how the heavens looked from the Earth before the dawn of electric light.

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PHOTO BY: Getty Images

Arches National Park (Utah)

If there’s one state stargazers should be sure not to miss, it’s Utah, which boasts the country’s greatest number of certified dark sky national parks, with five: Arches, Bryce, Canyonlands, Capitol Reef and Zion. Arches stands out with more than 2,000 signature sandstone arches that form dramatic backdrops for the celestial show overhead. For the best viewing spots, avoid the lights of Moab to the south and head north to the Balanced Rock picnic area, the Garden of Eden viewpoint, Panorama Point and the Windows section. Under the right conditions, you might even see Saturn’s rings with standard binoculars. Ranger-led stargazing programs, during which rangers introduce visitors to the wonders of the night sky followed by stargazing and telescope viewing, take place in spring and fall around the new moon at Panorama Point or the park’s visitor center. These events rotate between Arches and nearby Canyonlands.
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PHOTO BY: Deb Snelson/Getty Images

Big Bend National Park (Texas)

Thanks to its remote desert location and low humidity, this sprawling park in southwestern Texas has the least light pollution of any other national park in the continental U.S. No wonder, as the song says, “The stars at night are big and bright, deep in the heart of Texas.” You can attend one of Big Bend’s star parties, when amateur astronomers gather to observe the night sky together; take a guided moonlight walk; or use your binoculars on your own to enjoy an evening of meteor showers, constellation spotting or Milky Way viewing. On a clear night, countless stars will dazzle you, including from the Andromeda Galaxy, 2.5 million light years away.
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PHOTO BY: Kotomi Ito/Getty Images

Bryce Canyon National Park (Utah)

Marry the world’s largest collection of hoodoos (irregular columns of rocks) with one of the country’s darkest night skies and you have pure magic. At Bryce you can watch the Milky Way slash a silvery arc across the sky while thousands of stars illumine the park’s otherworldly rock formations. Stargazing is serious business here. Park rangers and volunteer astronomers operate about 100 astronomy programs per year. They include constellation tours, when rangers with lasers point out constellations visible in the night sky, and one- to two-mile-long full moon hikes, when the interplay of shadows and moonlight lend the hoodoos an eerie glow. For an overdose of celestial majesty, plan your trip around the four-day Annual Astronomy Festival in late June and participate in a collective astronomy art project, which entails creating watercolor paintings of planets in our solar system and an astronomical art “masterpiece” to unveil on the last day of the festival.
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PHOTO BY: Jon Hicks/Getty Images

Death Valley National Park (California)

America’s driest national park — a sprawling 3.4-million-acre desert — makes an ideal setting for admiring the stars and, if you’re lucky, for spotting meteors. Death Valley nights are so dark that the International Dark-Sky Association classifies them at the highest (Gold Tier) level, meaning that light pollution is so low that you see “views close to what could be seen before the rise of cities.” Many heavenly bodies viewed from Death Valley aren’t visible with the naked eye anywhere else in the world. For an introduction to the cosmos, join a ranger program during the cooler winter to learn about topics including space science, planetary science, space exploration, light pollution and the lore surrounding our night skies. Or visit during the annual Dark Sky Festival each spring, which includes special ranger programs; guest speakers from organizations such as NASA; and the Exploration Fair, where scientists from NASA, Caltech, the SETI Institute and other groups offer demonstrations to engage visitors. If you’re on your own, head to Badwater Basin, Harmony Borax Works, Mesquite Flat Sand Dunes or Zabriskie Point, favorite spots for astrophotographers looking to capture their night images.
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PHOTO BY: Carlos Fernandez/Getty Images

Grand Canyon National Park (Arizona)

Yes, the iconic Grand Canyon, one of the World’s Seven Natural Wonders, is clearly the main attraction at this park. But stick around after dark and you’ll be rewarded with stellar views of another kind. See the Milky Way cast your shadow on the Earth on a moonless night. Or thrill to a tableau of star clouds, nebulae, meteor showers and even planets like Mars, Jupiter and Saturn. Key stargazing spots on the South Rim include Desert View Watchtower, a mecca for snapping award-worthy images of the watchtower with a Milky Way backdrop; Mather Point; and Moran and Lipan points, both right off of Desert View Drive. On the canyon’s less-visited North Rim, you can have the stars all to yourself at Bright Angel Point.

In mid-June, visitors can join a free star party on the South Rim with the Tucson Amateur Astronomy Association and on the North Rim with the Saguaro Astronomy Club of Phoenix, to enjoy astronomy talks, constellation tours and telescope viewings. Night sky photography workshops and constellation talks take place throughout the year.
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PHOTO BY: James Ronan/EyeEm/Getty Images

Great Basin National Park (Nevada)

What makes Great Basin such a stargazing superstar? It has the ideal conditions, with high elevation and low humidity. It offers rare deep-space viewing from the Great Basin Observatory, the first research-grade observatory built in a U.S. national park. And as one of the least visited parks — it had only 120,248 visitors in 2020 — you can admire the night skies with hardly anyone else around.

On clear, moonless nights, head to such popular viewing spots as the Baker Archaeological Site and Mather Overlook to be awed by countless stars and planets (note that stars twinkle but planets don’t), meteor showers, man-made satellites, the Andromeda Galaxy and the Milky Way. From May through September, astronomy programs offer ranger talks and full moon hikes, telescope viewing at the astronomy amphitheater and solar telescope viewing from the Lehman Caves Visitor Center. On select summer evenings, hop aboard the Great Basin Star Train in the nearby town of Ely, guided by Great Basin National Park’s Dark Rangers. Along the way, you can disembark and use high-powered telescopes to see distant planets and deep-space objects. Finally, come for the annual Astronomy Festival, Sept. 22-24, to enjoy guest speakers, photo workshops, telescope viewings and tours of the Great Basin Observatory.
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PHOTO BY: Steve Burns/Getty Images

Voyageurs National Park (Minnesota)

Stars aren’t the only things that shine at this remote water-based park near the Canadian border. When conditions are right, the aurora borealis lights up the night sky with its shimmering streaks of blue, green, purple and red. While these rare light phenomena can’t be forecast, winter’s longer nights increase the chances of seeing them. While watching for the northern lights, keep a lookout for the Milky Way, satellites, shooting stars and other celestial objects. Voyageurs often hosts a three-day star party in August, with special ranger programs, Perseid meteor shower viewing, constellation tours and solar system walks.

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Award-winning travel writer Veronica Stoddart is the former travel editor of USA Today. She has written for dozens of travel publications and websites.

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A Mystery Rocket Left A Crater On The Moon – Forbes

Published

19 hours ago

June 27, 2022

Harry Miller

While we think of the moon as a static place, sometimes an event happens that reminds us that things can change quickly.

On March 4, a human-made object (a rocket stage) slammed into the moon and left behind a double crater, as seen by NASA’s Lunar Reconnaissance Orbiter (LRO) mission.

Officials announced June 23 that they spotted a double crater associated with the event. But what’s really interesting is there’s no consensus about what kind of rocket caused it.

China has denied claims that the rocket was part of a Long March 3 rocket that launched the country’s Chang’e-5 T1 mission in October 2014, although the orbit appeared to match. Previous speculation suggested it might be from a SpaceX rocket launching the DISCOVR mission, but newer analysis has mostly discredited that.

Here’s what the March 4 rocket crash site looked like from a wider field of view.

NASA/GSFC/Arizona State University

On a broader scale, the value of LRO observations like this is showing how the moon can change even over a small span of time. The spacecraft has been in orbit there since 2009 and has spotted numerous new craters since its arrival.

It’s also a great spacecraft scout, having hunted down the Apollo landing sites from orbit and also having tracked down a few craters from other missions that slammed into the moon since the dawn of space exploration.

It may be that humans return to the moon for a closer-up look in the coming decade, as NASA is developing an Artemis program to send people to the surface no earlier than 2025.

LRO will also be a valuable scout for that set of missions, as the spacecraft’s maps will be used to develop plans for lunar bases or to help scout safe landing sites for astronauts.

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