Discovered under Greenland ice: a massive meteor impact crater the size of New York City

By Tom Yulsman | November 16, 2018 3:16 pm
Meteor impact in Greenland gouges out huge crater

An international team of scientists has discovered a massive meteor crater under a glacier at the edge of the Greenland ice sheet. This artist’s rendition shows what the meteor impact might have looked like. (Source: NASA’s Goddard Space Flight Center/Jefferson Beck)

A very curious feature has long been visible in satellite images of Greenland’s massive ice sheet, but until now, no one really knew for sure what formed it.

Greenland meteor impact crater

The edge of the Greenland Ice Sheet includes the semi-circular feature seen in this image acquired by NASA’s Aqua satellite on July 17, 2918. Beneath it is a newly discovered meteor impact crater. (Source: NASA Worldview)

You can see the feature for yourself in the satellite image at right — look for the conspicuously semi-circular edge to the ice sheet.

As it turns out, that semi-circular shape hints at what’s below a layer of ice more than a half mile thick: a massive impact crater that has been hiding in plain site.

Research shows that it was gouged out of Greenland’s bedrock by a large iron meteorite more than a half mile wide. The object crashed to Earth less than 3 million years ago and possibly as recently as 13,000 years ago. The resulting bedrock basin subsequently was covered by ice. And today, the edge of that ice traces the edge of the crater down below. Read More

MORE ABOUT: geology

Stunning satellite images and animations offer a sobering perspective on California’s raging infernos

By Tom Yulsman | November 10, 2018 2:17 pm
The raging Camp Fire inferno in Northern California

Data from the Landsat 8 satellite were used to create this image of the Camp Fire in Northern California on November 8, 2018, around 10:45 a.m. local time. (Source: NASA Earth Observatory)

In all the many years that I’ve covered wildfire, I don’t believe I’ve encountered anything like what we’ve seen with the Camp Fire blazing in California’s northern Sierra Nevada mountains. What really shocked me was the speed with which this cataclysmic inferno progressed to become what appears to be the most destructive in state history.

In a flash, an estimated 6,713 structures  were destroyed in the town of Paradise. “It’s phenomenal how fast the fire spread,” said Scott McLean, the deputy chief of the California Department of Forestry and Fire Protection, quoted in the N.Y. Times.

The Landsat 8 satellite image above offers an incredible view of the inferno. It was created using Landsat bands 4-3-2 — visible light — along with shortwave-infrared light to highlight active portions of the fire.

The Camp Fire started around 6:30 a.m. Pacific Standard Time, and by 8:00 p.m., it had already burned 20,000 acres. As I’m writing this on the morning of Saturday, Nov. 10, the fire has consumed 100,000 acres — half the size of New York City — and is about 20 percent contained, according to the latest update from CalFire. (Access the latest CalFire info on the fire here.)

To the south, the Woolsey and Hill fires are burning just west of Los Angeles. They’ve so far consumed about 75,000 acres.  You can see smoke from these blazes, as well as the Camp Fire, in this video:

Smoke from the Woolsey and Hill blazes is visible toward the bottom of the frame. The Camp Fire is toward the top.  Read More

Astronauts spy coffin-shaped object bigger than Manhattan slouching toward a “graveyard” north of Antarctica

By Tom Yulsman | October 31, 2018 3:23 pm

Source: NASA Earth Observatory.

Seriously, this gargantuan coffin-like object really was photographed by an astronaut aboard the International Space Station on September 23, 2018.

If you guessed that it is an iceberg, you are right.


A broader view of B-15T, from NASA’s Terra Satellite. (Source: NASA Earth Observatory)

Known rather unimaginatively as B-15T, the spooky, Brobdingnagian berg is seen here adrift in the South Atlantic Ocean between South Georgia and the South Sandwich Islands. NASA’s Earth Observatory published the photograph today as its image of the day.

And the day is, of course, Halloween.

Read More

CATEGORIZED UNDER: Antarctic, Miscellaneous, select, Top Posts

A dust storm in Greenland? Beautiful satellite images show one far north of the Arctic Circle

By Tom Yulsman | October 17, 2018 10:49 am
A large dust plume — 'glacial flour' — blows from a valley on Greenland's east coast

A large plume of dust is seen streaming from a valley on Greenland’s east coast in this image acquired by the European Space Agency’s Sentinel-2 spacecraft on September 29, 2018. (Source: NASA Earth Observatory)

In late September, a dust storm erupted in a seemingly unlikely place: high in the Arctic in Greenland.

It was nothing compared to a Saharan dust storm. Even so, it was large enough to be visible from space. You can see it in the Sentinel-2 satellite image above: a grayish plume of fine silt being swept up by northwesterly winds. The source: a dry bed of a braided river valley that ends in Scoresby Sound on Greenland’s east coast.

This is about 80 miles northwest of Ittoqqortoomiit, a village at a latitude of 73 degrees North, according to NASA’s Earth Observatory. That places the plume at nearly 700 miles north of the Arctic Circle.

The dust in Greenland is mainly glacial flour, a fine powder created as a glacier scrapes over bedrock. The flour is carried downstream of  the glacier by meltwater streams. In the image above, glacial flour discolors Scoresby Sound where the outwash plain reaches the water. Read More

Visualization of Pacific ocean temperatures shows El Niño brewing, heralding possible winter weather impacts

By Tom Yulsman | October 12, 2018 5:58 pm
El Niño visualizations shows El Niño brewing

This animation shows how sea surface temperatures have departed from the long-term average, from August through early October 2018. (Animation by; data from NOAA’s Environmental Visualization Lab.)

It’s still not here yet, but El Niño sure looks like it’s coming.

In its latest forecast, NOAA’s Climate Prediction Center says there is a 70 to 75 percent chance that El Niño will form “in the next couple of months and continue through the Northern Hemisphere winter 2018-19.” If the forecast turns out to be correct, the El Niño could influence weather around the world.

El Niño is typically associated with an extended Pacific jet stream and amplified storm track, boosting the odds of wetter than average conditions across the southern tier of U.S. states. Should things play out this way (and they may not!), it could bring at least some relief for parts of the drought-stricken Southwest.

One of the factors behind the Climate Prediction Center’s increasing confidence that El Niño is coming can be seen in the visualization above. It shows how sea surface temperatures have evolved each week from August through early October — specifically, how those temperatures have differed from the 1985-2012 average.

Pay particular attention to the equator off the coast of South America and extending west to the middle of the Pacific. See the blue tending to give way to red? This is indicative of warming surface waters. As Emily Becker, a NOAA research scientist, puts it in a post at the ENSO Blog: Read More

CATEGORIZED UNDER: Climate, Drought, ENSO, select, Top Posts, Weather

Watch the lights blink out in Michael’s aftermath, as seen in before and after views from space

By Tom Yulsman | October 12, 2018 11:03 am
Imagery from the NOAA-20 satellite on Oct. 6 and 12, 2018. (Images:

Imagery from the NOAA-20 satellite on Oct. 6 and 12, 2018. (Images: University of Wisconsin SSEC. Animation: Tom Yulsman)

Hurricane Michael tore into the Florida Panhandle with winds up to 155 miles per hour, pushing up a flooding storm surge of nine to 14 feet, causing buildings to explode, and toppling countless trees.

Another impact was widespread power outages. Just how widespread is visible in the animation above. I created it using before-and-after nighttime images from the NOAA-20 satellite, one on Oct. 6 and the other on Oct. 12.

The imagery data come from the Visible-Infrared Imaging Radiometer Suite instrument aboard the satellite. VIIRS includes a Day Night Band that can reveal power outages. In this case, city lights in the path of Michael blink out, from the Florida Panhandle northeastward into east-central Georgia. Read More

Hurricane Michael: dramatic satellite view of the monster’s eye as it buzz-saws into the Florida coast

By Tom Yulsman | October 11, 2018 9:08 pm

An animation of images captured by the GOES-16 weather satellite shows Hurricane Michael making landfall along the Florida Panhandle on Oct. 10, 2018. (Source: Rick Kohrs, University of Wisconsin /SSEC)

The utter devastation wrought by Hurricane Michael’s storm surge and 155-mph winds simply boggles the mind.

“It appears that the impact of the hurricane was more like a bomb than a hurricane,” National Public Radio’s Tom Gjelton reported today. “Buildings literally exploded from the force of the wind.”

Literally exploded is no exaggeration, as this aerial footage showing the destruction in Mexico Beach, Florida, shows pretty clearly:

The view from space of the monster storm cutting into the Florida Panhandle coast like a buzz saw is both terrifying and strangely mesmerizing. Check it out by clicking on the screenshot at the top of this post. Read More

Here’s what the devastating flooding from Florence looks like from space

By Tom Yulsman | September 19, 2018 10:27 am
An animation of before and after images acquired by NASA's Terra satellite shows flooding in the wake of Florence across southeastern North Carolina and northeastern South Carolina. (Source: Modified from CIMSS Satellite Blog)

An animation of before and after images acquired by NASA’s Terra satellite shows flooding in the wake of Florence across southeastern North Carolina and northeastern South Carolina. (Source: Modified from CIMSS Satellite Blog)

You’ve probably seen imagery shot in the Carolinas showing the devastating flooding that Hurricane Florence left its wake. Now, check out what that flooding looks like from space — in the before-and-after animation above of false-color satellite images.

The images were acquired by NASA’s bus-sized Terra satellite, which circles Earth in a polar orbit 483 above the surface. The before image was captured on August 26th; the after image on September 18th.

Flooded waterways in the post-storm image appear in dark blue. As I’m writing this on Sept. 19, at least 16 rivers remain at a major flood stage. And others have yet to crest. Read More

Meanwhile, in the Pacific…

By Tom Yulsman | September 13, 2018 3:23 pm

Colors on this map show where and by how much monthly sea surface temperature differed from the 1981 to 2010 average during August 2018. (Source: NOAA)

As Hurricane Florence began lashing the Carolinas this morning, another potentially disruptive atmospheric and oceanic phenomenon continues to brew thousands of miles away in the Pacific: El Niño.

El Niño weather impacts. (Source: NOAA)

El Niño weather impacts. (Source: NOAA)

It’s not here yet, according to the National Oceanic and Atmospheric Administration’s latest monthly analysis, published today. But forecasters continue to favor its arrival this fall, pegging the odds at 50 to 55 percent. By winter, the chances rise to 65 to 70 percent.

We should care because what happens in the Pacific doesn’t stay in the Pacific. Here in the United States, El Niño tends to amplify winter storm tracks across the southern tier of the country, bringing wetter conditions. Meanwhile, farther north, it tends to be warmer and drier than average. (Click on the thumbnail to see typical winter weather impacts during El Niño episodes.) Read More

Staring straight into the eye of a monster

By Tom Yulsman | September 12, 2018 8:06 pm

As Florence swirled toward the Carolinas today, an astronaut took some chilling photos of the hurricane


They eye of Hurricane Florence, as seen from the International Space Station on Sept. 12, 2018 (Source: ESA/NASA—Alexander Gerst)

“Ever stared down the gaping eye of a category 4 hurricane? It’s chilling, even from space.”

So writes Alexander Gerst, a European Space Agency astronaut aboard the International Space Station who shot this stunning photo looking straight down into the eye of fearsome Hurricane Florence.

As of 5 p.m. EDT on Wednesday, the hurricane was bearing down on Carolina coastal areas with maximum sustained winds of 120 miles per hour — a modest weakening in recent hours, according to the National Hurricane Center. At the same time, the inner-core and outer wind fields of the storm have continued to expand. That means the cyclone’s total energy has increased, and a bigger area is experiencing the storm’s wrath.


“Watch out, America!,” writes Alexander Gerst. “Hurricane Florence is so enormous, we could only capture her with a super wide angle lens from the International Space Station, 400 km directly above the eye. Get prepared on the East Coast, this is a no-kidding nightmare coming for you. (Source: ESA/NASA—Alexander Gerst)

Florence’s increasing total energy is pushing up gargantuan amounts of sea water ahead of it. This will inevitably result in a “significant storm surge event,” the hurricane center says. Read More



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

See More


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

Collapse bottom bar