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Category Archives: Earth

Did Ancient Supernovas Change Earth’s Climate?

Visible, infrared, and X-ray image of Kepler’s supernova remnant located about 13,000 light-years away. The bubble of ionized gas is about 30 light-years across. Credit: NASA, ESA, R. Sankrit and W. Blair (Johns Hopkins University).

Supernovas are some of the most powerful and energetic events in the entire Universe. When a dying star explodes you wouldn’t want to be anywhere nearby—fresh elements are nice and all, but the energy and radiation from a supernova would roast any planets within tens if not hundreds of light-years in all directions. Luckily for us we’re not in an unsafe range of any supernovas in the foreseeable future, but there was a time not very long ago (in geological terms) that these stellar explosions occurred nearby (in astronomical terms) and in 2016 scientists found the “smoking gun” evidence at the bottom of the ocean.

What’s more, the arrival of the iron-rich fallout from those stellar explosions seems to coincide with ancient global temperature changes*, the most recent dated near the start of the last major ice age which brought lower sea levels, widespread glaciation…and eventually the rise of the first modern humans.

Read more at Universe Today here: Nearby Supernovas Showered Earth With Iron

*Note: the changes in climate referred to here are not the same as the climate change we are witnessing today. Not only are we now seeing rapid warming of land and sea temperatures globally, but today’s forcings are the result of increasing greenhouse gases like carbon dioxide in the atmosphere—not radioactive iron from exploding stars.

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Clementine: Lost and Gone Forever, But Never Forgotten!

The far side of the Moon imaged by Clemetine's Star Tracker camera in 1994.

The far side of the Moon imaged by Clementine’s Star Tracker camera on April 1, 1994.

One of my all-time favorite space images is this little gem from the Clementine mission to the Moon, launched January 25, 1994. It features a view from beyond the far side of the Moon, illuminated by reflected light off the Earth off frame to the left. The Moon is blocking the disc of the Sun with the glow of the solar corona and an overexposed Venus shining brightly in front of a background of stars. It may have been taken on April 1 but this picture is no joke—it’s absolutely beautiful!

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Meteors May Make Your Hair Hiss

Meteors typically occur about 50 to 75 miles above the ground. This one was photographed from above by astronaut Ron Garan aboard the ISS in August 2011. (NASA image)

Meteors typically occur about 50 to 75 miles above the ground. This Perseid meteor was photographed from above by astronaut Ron Garan aboard the ISS in August 2011. (NASA image)

Have you ever gone outside on a cold, clear night to watch a meteor shower and witness a super-bright fireball racing across the sky so brilliantly that you could swear you could hear it? Turns out the sizzling noise might not have been all in your head after all…but rather on it. (And here’s science to prove it.)

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Voyager 1’s Famous Long-Distance Valentine

Venus, Earth, Jupiter, Saturn, Uranus and Neptune as seen by Voyager 1 in 1990 (Credit: NASA)

If you’re in love with space then you’ll fall head over heels for this: it’s a picture of Earth taken from the Voyager 1 spacecraft after it passed the orbit of Pluto back in 1990—on Valentine’s Day, no less. That image of our planet from almost 4 billion miles away inspired Carl Sagan to write his famous “Pale Blue Dot” passage, which reminds us that we are all just riding on “a mote of dust suspended in a sunbeam.”

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Earth: Enhanced! NASA’s EPIC Global Views Get an Online Image Boost

An EPIC Natural Color image (left) and an Enhanced Color image (right) of the Earth on January 26, 2017. Credit: NASA/NOAA

From a vantage point of nearly one million miles away NASA’s EPIC camera aboard NOAA’s DSCOVR satellite captures an image of the entire Earth every 1-2 hours as it rotates. For the last year and a half or so these pictures have been uploaded on the EPIC website for public viewing and use as they originally look to the EPIC instrument; now there’s an option to view Earth in “enhanced” mode, which boosts the contrast, saturation, and overall appearance to make landforms and clouds more apparent—and you can even zoom in too, in true CSI-style!

“The ‘enhanced’ color images make land features more visible,” said Sasha Marshak, DSCOVR deputy project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This is achieved by enhancing low intensity pixel values. The effect of atmospheric haze caused by air molecular scattering and attenuation of solar light by ozone has been also removed.”

Read more from NASA here: NASA Makes an EPIC Update to Website for Daily Earth Pics

NOAA’s Newest Satellite Sends Its First Pictures of Earth…and the Moon!

GOES-16 image of the Moon beyond Earth's limb taken Jan. 15. GOES-16 uses the Moon for calibration purposes. (NASA/NOAA)

GOES-16 image of the Moon beyond Earth’s limb taken Jan. 15. GOES-16 uses the Moon for calibration purposes. (NASA/NOAA)

America’s newest next-generation Earth observing weather satellite, NOAA’s GOES-16, has returned its first high-definition images of Earth—one of which even includes the Moon!

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