Earth Archives

January 24, 2022January 24, 2022 by Evan Gough

It’s Been Constantly Raining Meteors on Mars for 600 Million Years. Earth too.

An impact crater on Mars. Image Credit: NASA

New research shows that Mars has faced a constant rain of meteors during the last 600 million years. This finding contradicts previous research showing that the impact rate has varied, with prominent activity spikes. Why would anyone care how often meteors rained down on Mars, a planet that’s been dead for billions of years?

Because whatever Mars was subjected to, Earth was also likely subjected to.

Who wouldn’t want to know our planet’s history?

January 15, 2022January 17, 2022 by Nancy Atkinson

Tonga’s Incredible Underwater Volcano Eruption Seen From Space

The Tonga Hunga volcanic eruption sent a tsunami across the Pacific. Air pressure disturbances from the tsunami distorted GPS signals. GOES imagery courtesy NOAA,NESDIS. — The Tonga Hunga volcanic eruption as seen by a GOES satellite. Credit: NOAA,NESDIS.

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:

January 11, 2022January 11, 2022 by Evan Gough

Nearby Supernovae Were Essential to Life on Earth

Distant past supernovae could be linked by cosmic ray particles to climate change on Earth and changes in biodiversity. Courtesy: Henrik Svensmark, DTU Space.

It’s almost impossible to comprehend a supernova explosion’s violent, destructive power. An exploding supernova can outshine its host galaxy for a few weeks or even months. That seems almost impossible when considering that a galaxy can contain hundreds of billions of stars. Any planet too close to a supernova would be completely sterilized by all the energy released, its atmosphere would be stripped away, and it may even be shredded into pieces.

But like many things in nature, it all comes down to dose.

A certain amount of supernova activity might be necessary for life to exist.

January 10, 2022January 10, 2022 by Evan Gough

The Early Earth was Really Horrible for Life

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

Earth has had a long and complex history since its formation roughly 4.5 billion years ago. Initially, it was a molten ball, but eventually, it cooled and became differentiated. The Moon formed from a collision between Earth and a protoplanet named Theia (probably), the oceans formed, and at some point in time, about 4 billion years ago, simple life appeared.

Those are the broad strokes, and scientists have worked hard to fill in a detailed timeline of Earth’s history. But there are a host of significant and poorly-understood periods in the timeline, lined up like targets for the scientific method. One of them concerns UV radiation and its effects on early life.

A new study probes the effects of UV radiation on Earth’s early life-forms and how it might have shaped our world.

December 15, 2021December 15, 2021 by Nancy Atkinson

The Recent Killer Tornado’s Track is Visible From Space

On December 12, 2021, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite acquired this natural-color image of the tornado track across western Kentucky near Mayfield. This area endured some of the worst damage of the fierce storm front. Credit: NASA/NOAA.

During the night of December 10, 2021, severe weather tore through several US states, Arkansas, Illinois, Kentucky, Mississippi, Missouri and Tennessee. At least 70 tornado-like events were reported, and one storm cell was tracked on radar for approximately four hours as it traveled for more than 400 km (250 miles.)

While the destruction these storms left behind is visible even from space, the heartbreaking devastation on the ground is sobering; over 100 people killed, with hundreds more injured.

December 14, 2021December 14, 2021 by Evan Gough

Life on Earth Needed Iron. Will it be the Same on Other Worlds?

Earth as seen by the JUNO spacecraft in 2013. Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill.

A lot has to go right for a planet to support life. Some of the circumstances that allow life to bloom on any given planet stem from the planet’s initial formation. Here on Earth, circumstances meant Earth’s crust contains about 5% iron by weight.

A new paper looks at how Earth’s iron diminished over time and how that shaped the development of complex life here on Earth. Is iron necessary for complex life to develop on other worlds?

December 9, 2021December 9, 2021 by Evan Gough

NASA’s New Asteroid Impact Monitoring System Comes Online

This diagram shows the orbits of 2,200 potentially hazardous objects as calculated by JPL’s Center for Near Earth Object Studies (CNEOS). Highlighted is the orbit of the double asteroid Didymos, the target of NASA’s Double Asteroid Redirect Test (DART) mission. Credit: NASA/JPL-Caltech

An asteroid striking Earth is a genuine possibility. There are tens of thousands of asteroids classified as Near-Earth Asteroids (NEAs), and we’re finding around 3,000 more each year. The number of new detections will see an uptick in the next few years as better survey telescopes come online.

Now NASA has developed a new system to classify all those asteroids and better evaluate impact probabilities.

December 7, 2021December 7, 2021 by Evan Gough

Asteroid Apophis’ 2029 Flyby Will Provide a Bonanza of Asteroid Science

The asteroid 99942 Apophis. Image Credit: NASA/Caltech/JPL

If NASA and other space agencies don’t want us to freak out about asteroids colliding with Earth, why do they give them names like Apophis? It sounds apocalyptic.

Apophis was the ancient Egyptian god of Chaos. He was an evil serpent that dwelled in endless darkness, the enemy of light and truth. So when they informed us that an asteroid named Apophis was due for a close encounter with Earth in 2029, people were understandably anxious. After all, Earth’s previous dominant inhabitants were evicted by an asteroid.

December 6, 2021December 6, 2021 by Evan Gough

Did the Earth’s Water Come From the Sun?

The sun, solar winds and asteroid Itokawa. Image Credit: Curtin University.

Where did Earth’s water come from? Comets may have brought some of it. Asteroids may have brought some. Icy planetesimals may have played a role by crashing into the young Earth and depositing their water. Hydrogen from inside the Earth may have contributed, too. Another hypothesis states the collision that formed the Moon gave Earth its water.

There’s evidence to back up all of these hypotheses.

But new research suggests that the Sun and its Solar Wind may have helped delivered some water, too.

November 26, 2021November 26, 2021 by Matt Williams

The Severe Pacific Northwest Flooding Seen From Space

The State of Washington and the Province of BC are in a state of emergency following days of severe wind, rain, and flooding. The situation began when an “atmospheric river” (a plume of moisture) extended over the Pacific Northwest, triggering severe rainfall that caused already-rising rivers to overflow. This led to blocked roads, mudslides, fallen bridges, and thousands of animals drowning in farmland areas.

This extensive damage was photographed from space by Earth observation satellites, one of which was the European Space Agency’s (ESA) Copernicus Sentinel mission and the International Space Station (ISS). These images captured the extent of the floods in the Nooksack and Fraser River valleys this week, which both spilled over their banks this week, leading to washed-out roads and forcing the evacuation of thousands of people.