Earth Observation Archives

March 3, 2023March 3, 2023 by Nancy Atkinson

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.

November 16, 2022November 16, 2022 by Matt Williams

Greenland’s ice Loss is Worse Than We Thought

Cumulative melt days on the Greenland Ice Sheet for the 2022 melt season (left) and difference from the 1981 to 2010 average melt days for the same period (right). Credit: NSIDC/T. Mote, University of Georgia

Climate change is the single greatest threat facing our planet today. Thanks to excess carbon emissions that have been growing steadily since the mid-20th century, average temperatures continue to rise worldwide. This leads to feedback mechanisms, such as rising sea levels, extreme weather, drought, wildfires, and glacial melting. This includes the Arctic Ice Pack, the East Antarctic glacier, and the Greenland Ice Sheet (GrIS), which are rapidly melting and increasing global sea levels.

Worse than that, the disappearance of the world’s ice sheets means that Earth’s surface and oceans absorb more heat, driving global temperatures even further. According to a new NASA-supported study by an international team of Earth scientists and glaciologists, the Greenland Ice Sheet is melting at an accelerating rate, much faster than existing models predict. According to these findings, far more ice will be lost from Greenland during the 21st century, which means its contribution to sea-level rise will be significantly higher.

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October 8, 2022October 8, 2022 by Nancy Atkinson

The Methane Released From the Damaged Nord Stream Pipeline is Visible From Space

On September 20, 2022 a GHGSat satellite observed the area of the Nordstream pipeline break, and saw an estimated emission rate of methane of 79,000 kg per hour – making it the largest methane leak ever detected by GHGSat from a single point-source. Credit: GHGSat and ESA.

On September 26, 2022, leaks were discovered in the underwater Nord Stream 1 and 2 gas pipelines, located near Denmark and Sweden. Both pipelines are owned by Russia and were built to transport natural gas from Russia to Germany through the Baltic Sea. Officials have said the leaks were caused by deliberate action, not accidents, and were likely intentional sabotage. While accusations have abounded, the motives behind the damage are not yet known.

Seismic disturbances in the Baltic Sea were detected, and officials said that while neither pipeline was transporting gas at the time of the blasts, they still contained pressurized methane, which is the main component of natural gas. The methane has now spewed out, producing a wide stream of bubbles on the sea surface which are visible from various satellites in Earth orbit.

March 2, 2022March 2, 2022 by Matt Williams

Ukrainians urge satellites to publicly share real-time images of the Russian invasion

On the morning of February 24th, after years of proxy conflict in the border region, Russia invaded the neighboring country of Ukraine. This invasion was the culmination of eight years of conflict that began with the removal of Ukrainian President Viktor Yanukovych (a long-time ally of Russian President Vladimir Putin) and Russia’s subsequent annexation of Crimea. This invasion has prompted the global community to mobilize and find ways to support Ukraine!

For instance, you have Earth Observatory System Data Analytics (EOSDA), a California-based “all-in-one cloud workspace” for Earth observation solutions. In a recent statement, EOSDA CEO Max Polyakov appealed to satellite imagery firms and space agencies worldwide to share their recent and real-time high-to-medium resolution optical and radar satellite imagery with EOSDA to assist military and humanitarian aid efforts in the region.

January 15, 2022January 17, 2022 by Nancy Atkinson

Tonga’s Incredible Underwater Volcano Eruption Seen From Space

An undersea volcano erupted near the Pacific island of Tonga, and several satellites caught the incredible explosion in action. The blast of the Hunga Tonga Hunga Ha’apai volcano created a plume of ash, steam and gas mushrooming above the Pacific Ocean, with a quickly expanding shockwave visible from orbit. Japan’s Himawari-8 weather satellite recorded this dramatic video:

November 11, 2021November 11, 2021 by Nancy Atkinson

Landsat 9’s First Images are Here

Landsat 9 carries two instruments designed to work together to capture a broad range of wavelengths: the Operational Land Imager 2 and the Thermal Infrared Sensor 2. Data from both instruments are shown in this image. Credits: NASA

The latest satellite in the Landsat family of Earth observation spacecraft has collected its “first light” images of our planet. Landsat 9 launched on September 27, 2021 and it continues the nearly 50-year tradition of making critical observations to help with energy and water management, forest monitoring, human and environmental health, urban planning, disaster recovery and agriculture.

September 29, 2021September 29, 2021 by Nancy Atkinson

Landsat 9 Joins a Fleet of Earth Observation Satellites

Landsat 9 lifted off from Vandenberg Space Force Base on September 27, 2021 on an an Atlas V 401 rocket. Credit: NASA

Earth has a new eye in orbit to monitor our changing planet.

Landsat 9 launched on September 27, 2021 continuing the Landsat family of satellite’s nearly 50-year tradition of making critical observations to help with energy and water management, forest monitoring, human and environmental health, urban planning, disaster recovery and agriculture.

July 10, 2021July 10, 2021 by Scott Alan Johnston

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

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.

May 30, 2021May 30, 2021 by Brian Koberlein

Teeny Tiny CubeSats Could Have Deployable Mirrors Like James Webb

Cubesats being launched from the ISS. Credit: NASA

When you think of a space telescope, you probably think of ones such as the Hubble, which probes deep space using precision optics. But optical space telescopes are also pointed at Earth, giving us detailed views of everything from weather, to traffic patterns, to the movement of military troops. While Earth-focused telescopes are extremely useful, they can also be fairly large and expensive to launch into space. But that could change with a new proposed design for cube satellites.

May 24, 2021May 24, 2021 by Nancy Atkinson

This is Currently the World’s Largest Iceberg

An enormous iceberg has calved from the western side of the Ronne Ice Shelf, lying in the Weddell Sea, in Antarctica. Image by the Copernicus Sentinel-1 mission. Credit: ESA

A gigantic chunk of ice recently broke off from an ice shelf in Antarctica, and is currently the world’s largest iceberg. The iceberg, dubbed A-76, measures around 4,320 square km (1,670 square miles) in size. At 170 km (106 miles) in length and 25 km (15 miles) wide, the iceberg is slightly larger than the Spanish island of Majorca, and bigger than the state of Rhode Island in the US.

A-76 was captured in the above image by ESA’s Copernicus Sentinel-1 satellite. Below is an animation of the iceberg calving off the Ronne Ice Shelf.