The World's Largest Iceberg Sets Sail for Adventure Beyond Antarctic Waters

Iceberg A23a seen from space. Credit: ESA.

In November 2023, the monster iceberg A23e finally dislodged from the seafloor after being grounded and stuck there for 40 years. A series of recent satellite images show that the mighty iceberg is now heading away from Antarctic waters, seeking fame and fortune in the high seas. A23a measures 4,000 sq kilometers in area and is over 280 meters thick, and is currently the world’s largest iceberg. Its first path will follow the Antarctic Circumpolar Current, heading towards South America.

Tiny Elephant Island, an ice-covered, mountainous island off the coast of Antarctica seen in the image above, has an area of only 215 sq km.

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Red Sprites are Best Seen from Space

Image of a red sprite taken from the International Space Station in October 2023 by Expedition 70 Commander, Dr. Andreas Mogensen. (Credit: ESA/DTU/ A. Mogensen)

Planet Earth is full of some truly awe-inspiring spectacles, but few are as intriguing as a sprite, which are officially known as a Transient Luminous Event (TLE) and consist of large-scale electric discharges that shoot upwards while occurring above the cloud tops in the Earth’s mesosphere at approximate altitudes of 50-90 km (31-56 mi). In October 2023, European Space Agency (ESA) astronaut, Dr. Andreas Mogensen, who is currently onboard the International Space Station (ISS) as Commander of the Expedition 70 mission, took an incredible image of a red sprite with the Davis camera as part of the Thor-Davis experiment and his Huginn mission.

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After Stalling Out for 40 Years, the Largest Iceberg in the World is on the Move

An animation from Copernicus Sentinel-1 images shows iceberg A23a’s movements from 2 November 2023, 14 November 2023 and 26 November 2023. Credit: ESA.

In 1986, a gigantic iceberg separated from the Fichner-Ronne ice shelf in West Antarctica. It was so big that it became grounded, stuck to the seafloor, and remained in position for 40 years. Finally, it has now been pushed off the seafloor and has begun drifting in the Weddell Sea to a region in the South Atlantic called Iceberg Alley. Designated A23a, this monster berg measures 4000 sq km (1,500 square miles) and is about 400 meters (1,300 feet) thick – the world’s largest.

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Follow a Simulated Journey of the Destruction of ESA’s Aeolus Mission

The Aeolus spacecraft orbited Earth and used lidar to study the winds in various parts of our atmosphere. It was brought back to Earth in a controlled re-entry on July 28th. Courtesy ESA.
The Aeolus spacecraft used lidar to study the winds in various parts of our atmosphere. It was brought back to Earth in a controlled re-entry on July 28th. Courtesy ESA.

On July 28th, the European Space Agency commanded its long-working Aeolus wind profile mission to re-enter Earth’s atmosphere. It did that and disintegrated into pieces over Antarctica. Of course, satellites do this often. But, Aeolus was different. It maneuvered its way into a safe re-entry profile, a first-of-its kind activity designed to avoid populated regions on Earth.

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Forest Fires in British Columbia are Bad This Year. THIRTY Times Worse Than Average

Heat and drought have fueled an unusually large outbreak of fire in Canada. Credit: NASA

This summer has seen a violent outbreak of forest fires across Canada and North America. According to the Canadian Interagency Forest Fire Center (CIFFC), there were 911 active fires across the country on July 13th, nearly 600 of which were characterized as “out-of-control.” More than half of these active fires are taking place in the provinces of British Columbia, driven by a combination of unusual heat, dry lightning, and drought. The situation is becoming increasingly common thanks to rising global temperatures, diminished rainfall, changing weather patterns, and other related effects of Climate Change.

Monitoring forest fires and other meteorological phenomena is an important task for which Earth Observation missions like NASA’s Aqua satellite were created. On July 12th, with six weeks left in the Canadian fire season, Aqua captured images of some of the largest fires over British Columbia using its Moderate Resolution Imaging Spectroradiometer (MODIS) instrument. The image above shows some of the biggest “hot spots” in the province, which produced dense plumes of smoke blowing eastward through the Rocky Mountains and into Alberta and the Northwest Territories.

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Phew, California’s Largest Reservoir is Nearly Full

Shasta Lake, California’s largest reservoir, filled to nearly 100 percent capacity, seen on May 29, 2023 as seen by the Operational Land Imager (OLI) on the Landsat 9 satellite. Credit: US Geological Survey/NASA Earth Observatory/Lauren Dauphin.

California residents will be glad to know their reservoirs are nearly full again after years of drought. New satellite photos show the levels of Shasta Lake, California’s largest reservoir, going from 31% capacity last November to nearly 100% in May 2023. The reservoir was filled with heavy rains and a significant mountain snowpack that melted into the nearby rivers.

This is the highest levels this lake has seen in over four years, following years of persistent and extreme drought in the US southwest. Scientists are working on ways to recharge ground reservoirs with any excess water, to minimize the effect of the next inevitable drought.

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Mount Everest from Space

Clouds gather on Nepal's sub-tropical side of the Himalayas with Mount Everest at the center of this photograph taken by an external high definition camera on the International Space Station as it orbited 263 miles above the Indian subcontinent. Courtesy NASA.
Clouds gather on Nepal's sub-tropical side of the Himalayas with Mount Everest at the center of this photograph taken by an external high definition camera on the International Space Station as it orbited 263 miles above the Indian subcontinent. Courtesy NASA.

Earth is a favorite target for the cameras and astronauts aboard the International Space Station (ISS). This week, NASA shared an amazing picture of the Himalayan mountain range as seen from space. This jagged set of mountains stretches out across Asia above the Indian subcontinent and is home to Mount Everest, the tallest mountain on Earth. It’s centered in the image.

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Why are Earth’s Hemispheres the Same Brightness? New Research Solves a 50-year-old Mystery.

The Blue Marble from Apollo 17
The Blue Marble image of Earth from Apollo 17. Credit: NASA

NASA’s Apollo program most notably explored the Moon. But it also helped us study the Earth as well, as it provided some of the first high-resolution images of our whole planet, like the famous “Blue Marble” photo taken by the Apollo 17 astronauts.

However, these full-Earth photos revealed a mystery.  Scientists expected that Earth’s two hemispheres, the north and south, would have different albedos, a difference in the amount of light they reflect. This is because Earth’s northern and southern hemispheres of Earth are quite different from each other. The southern hemisphere is mostly covered with dark oceans, while the northern hemisphere contains vast land areas that are much brighter than the oceans

Yet, when observing Earth from space, the two hemispheres appear equally bright.

This symmetry in brightness has been a puzzle for over 50 years. But now, a new study shows that the albedos are roughly the same because of the increased clouds and storms in the southern hemisphere.

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Light Pollution is Obscuring the Night Sky. RIP Stargazing

A startling analysis from Globe at Night — a citizen science program run by NSF’s NOIRLab — concludes that stars are disappearing from human sight at an astonishing rate. Image Credit: NOIRLab/NSF/AURA, P. Marenfeld

A citizen science initiative called Globe at Night has some sobering news for humanity. Our artificial light is drowning out the night sky for more and more people. And it’s happening more rapidly than thought.

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NASA Satellites can Pinpoint the Exact Locations of Excessive CO2 Emissions

Carbon dioxide in Earth's atmosphere if half of global-warming emissions are not absorbed. Credit: NASA/JPL/GSFC

In 2013, the National Oceanic and Atmospheric Administration (NOAA) reported that atmospheric concentrations of carbon dioxide (CO2) had reached four-hundred parts per million (ppm) for the first time since the Pliocene Era (ca. three million years ago). According to the IPCC’s Sixth Assessment Report (AR6), “excess carbon dioxide” in our atmosphere will result in a global average temperature increase of between 1.5 and 2 °C (2.7 and 3.6 °F) by 2030. This will significantly affect ecological systems worldwide, including species extinction, droughts, wildfires, extreme weather, and crop failures.

Aside from curbing emissions, these changes call for mitigation and adaptation strategies and climate monitoring. This is the purpose of NASA’s Orbiting Carbon Observatory (OCO) 2 and 3 missions, twin satellites that make space-based observations of CO2 in Earth’s atmosphere to understand the characteristics of climate change better. Using the world’s fifth-largest coal-fired power plant as a test case, a team of researchers used data from OCO 2 and 3 to detect and track changes in CO2 and quantify the emissions produced below.

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