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.
It may not be the first (or even second or third) satellite mission that comes to mind but NASA and JHUAPL’s TIMED mission continues to deliver invaluable data about Earth’s upper atmosphere over 15 years after its launch on Dec. 7, 2001. In fact its extended long-duration stay in orbit has allowed TIMED (Thermosphere Ionosphere Mesosphere Energetics and Dynamics) to completely change what we thought we knew about how the uppermost layers of our atmosphere react to incoming storms from the Sun…and how it’s being affected by increasing amounts of carbon dioxide from below.
Read more at TIMED Marches On — 15 Years and Counting
Third time was definitely a charm today for SpaceX, NASA, and NOAA as the Deep Space Climate Observatory (DSCOVR) launched from Cape Canaveral aboard a Falcon 9 rocket after two scrubbed attempts. Liftoff occurred at 6:03 p.m. EST on Wednesday, Feb. 11 into a clear sky as the Sun was setting – a truly picturesque backdrop for what turned out to be a perfect launch. Visibility was good enough to catch sight of the first stage separation and payload fairing jettison from the ground!
Watch the video replay above of the launch from the NASA TV feed.
DSCOVR will journey outwards to its destination at the Sun-Earth Lagrange point 1 (L1), located nearly a million miles away from Earth toward the Sun. There it will insert into a stable orbit from where it can observe both the Sun and Earth, monitoring various aspects of Earth’s climate as well as keeping an eye on potentially disruptive solar storms up to a full hour before they arrive at Earth.
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.
Originally posted April 22, 2009
Tell that to the Wilkins Ice Shelf.
At least 10,000 years old, the 1/3 mile wide span of ice that linked Antarctica to nearby Charcot Island broke apart on April 5, 2009, as expected by scientists watching worldwide. This collapse opens a path for icebergs from the rest of the disintegrating swath of ice to enter the open ocean, which they are currently beginning to do.
Now, with the Charcot Island connection broken for the first time in centuries, cracks are rapidly forming in the nearby bridge to Latady Island as well (above at top left). Scientists don’t expect this connection to last much longer. Weeks, maybe months.
The Wilkins Ice Shelf is part of the section of Antarctica that extends north toward the southernmost tip of South America. The collapse of its ice bridges is part of a trend of breakups across the continent, contributed to a 4ºF rise in polar temperatures since the 1960s. Such events pave the way for more ice to enter the ocean from Antarctic glaciers, possibly contributing to a global rise in sea levels. The 25-mile-long Wilkins Shelf is the largest to have come apart recently.
It’s a bleak warning of what’s to come, whether we choose to pay attention or not. We cannot expect to inhabit our world the way we do and not have an effect on it…see the wall chart at left from a display at San Diego’s Birch Aquarium. Let’s hope it’s not too late to make a change.
The image above is from the Chelys Earth Snapshot Site. It’s a great place to see hi-res satellite images from around the globe, updated daily. Most are not as dire as this but I felt it needed to be highlighted, especially in honor of Earth Day when we should all be conscious of the beauty – and fragility – of our own very special planet. We haven’t found another one yet that can house us, so it only makes sense to treat the one we have with utmost care.
Image credit: Chelys