Win a DVD of NOVA’s Excellent “Earth From Space”

Satellites give us views of our planet’s constantly-changing systems as never seen before (Earth From Space, ©PBS)

Earth… our home planet, a brilliant “blue marble” tirelessly turning through space on an endless journey around the Sun and across the galaxy. Basically a ball of  molten rock and metal, its relatively thin crust is mostly covered by a sea of liquid water as well as wrapped in a sea of air… and it’s the complex interaction between all of these things that have allowed life to evolve, thrive, and — so far, anyway — continue to exist on this one particular world.

But how exactly does this work? How, and why, do all of these different factors combine to make a habitable planet? Energy from the Sun, the movement of the atmosphere, the planet’s rotation, the constant churning of ocean currents,  the upwelling of materials from deep inside the Earth… all of these play essential roles every day in the survival of nearly every living thing on our planet — including us. To truly understand life on Earth, we must first understand the complex interactions of these forces, and more.

Luckily we have satellites, our “eyes in the sky” that let us look at the entire world on a daily basis and measure and monitor many different processes like never before, letting us see the otherwise invisible big picture of Earth From Space.

50 Unbelievable Facts About Earth: an Infographic

Do you know how long a tardigrade can survive in space? How much gold is in seawater? How long it’s been since it rained in Antarctica’s Dry Valleys? There are a whole lot of amazing facts about our planet and this infographic has 50 of them (and while seemingly unbelievable, they’re all true!) See the full version below:

Space Book Alert: Your Ticket to the Universe

Your Ticket to the Universe: A Guide to Exploring the Cosmos (Available for purchase from Smithsonian Books on April 2)

Every once in a while an astronomy book comes out that combines stunning high-definition images from the world’s most advanced telescopes, comprehensive descriptions of cosmic objects that are both approachable and easy to understand (but not overly simplistic) and a gorgeous layout that makes every page spread visually exciting and enjoyable.

This is one of those books.

Our Electric Earth at Night: the “Black Marble”

Suomi NPP satellite image of North and South America at night

In daylight our big blue marble is all land, oceans and clouds. But the night is electric.

This image of North and South America at night is a composite assembled from data acquired by the Suomi NPP satellite in April and October 2012. The new data was mapped over existing Blue Marble imagery of Earth to provide a realistic view of the planet.

The nighttime view was made possible by the new satellite’s “day-night band” of the Visible Infrared Imaging Radiometer Suite. VIIRS detects light in a range of wavelengths from green to near-infrared and uses filtering techniques to observe dim signals such as city lights, gas flares, auroras, wildfires, and reflected moonlight. In this case, auroras, fires, and other stray light have been removed to emphasize the city lights.

Although the view looking down from space is of a sparkling show, the downside of course is light pollution over major metropolitan areas which impede the view of the night sky from the ground. (Find out more at the International Dark Sky Association site.)

Read more (and watch a video of these nighttime images of Earth) below:

Blue Marble, Pale Blue Dot…whatever you call it, it’s Home

Photo of Earth and Moon captured by Voyager 1 on Sept. 18, 1977 (NASA)

35 years ago today, September 18, 1977, NASA’s Voyager 1 spacecraft turned its camera homeward just about two weeks after its launch, capturing the image above from a distance of 7.25 million miles (11.66 million km). It was the first time an image of its kind had ever been taken, showing the entire Earth and Moon together in a single frame… crescent-lit partners eternally paired in space.

I must say, it brings to mind a quote by the contentious British astrophysicist Sir Fred Hoyle (who famously coined the term “Big Bang”, albeit in disparagement) –

“Once a photograph of the Earth, taken from outside, is available – once the sheer isolation of the Earth becomes known – a new idea as powerful as any in history will be let loose.”

Whatever Hoyle had in mind, it’s quite something to look at your entire planet sitting there amidst the blackness of space and kow that everything that’s ever happened to all living things that we’ve ever known about, human or otherwise, has happened right there, on the surface of that sphere. And that we look awfully small from not very far away… 7.25 million miles is only just about a thirteenth the distance to the Sun (luckily Voyager was headed the other way!)

Of course, then there’s this famous bit of eloquence by the legendary Carl Sagan.

Read more here.

Goodbye, Earth!

If you haven’t seen this before, you’re probably not alone. It’s a video made from a series of several hundred images acquired by NASA’s MESSENGER spacecraft as it swung past Earth, departing forever on its journey to Mercury on August 2, 2005 — just a day shy of one year after its launch. Many blogs that are around today didn’t exist then (including Lights in the Dark!) and so there’s probably lots of people who haven’t had a chance to watch this.

I suggest you check it out. It’s very cool.

Canadarm Soars Above Waves of Aurora

The aurora australis glows beneath the ISS in this photo taken on July 15, 2012

Sparked by a coronal mass ejection emitted from a sunspot on July 12, Earth’s aurora leapt into action both at the north and south poles three days later. Here we can see a view of the southern lights, or aurora australis, shimmering in green waves below the Space Station’s Canadarm on July 15.

With 7 joints of rotation, the 17-meter-long Canadarm can move end-over-end across the exterior of the ISS (attaching to Power Grapple Fixtures at either end as it goes) to allow expedition crews to manipulate objects both large and small outside the Station. Launched in 2001, it’s one of the ISS’s most essential tools.

NASA astronaut and Expedition 32 flight engineer Joe Acaba recorded the series of images from the Station’s Tranquility node.

Image: NASA