A new seismic study shows that Earth has five inner layers, not four as long believed. Inside Earth's inner core is an *inner-inner* core, a ball of white hot iron 1300 km (800 miles) wide. science.anu.edu.au/news-events/ne…#Geology#earthquakes
Researchers at Australian National University developed a clever way to sense seismic waves reverberating inside the Earth. Those echoes made it possible for them to sense the growing metallic seed at the center of our planet. nature.com/articles/s4146…#Perspective
The innermost inner core is Earth's fifth layer. Which means it is the perfect setting for a movie sequel that merges The Core with The Fifth Element.
Quick reminder: No matter how weird the core of the Earth may be (and it seems plenty weird), it is definitely NOT spinning backwards.
If you saw this headline, or one like it, you might reasonably have thought the world has gone mad. The inside of the Earth is spinning backwards?
*But that is not at all what the actual research says.*
[a short thread] #RealityCheck
Key point: Earth's core rotates at almost exactly the same rate as the rest of the planet. Did in the past, still does so now. It rotates at the same speed to within 0.001%!
But even the research paper is confusing on that point: #RealityCheck nature.com/articles/s4156…
What's interesting here is that Earth's inner core rotates *almost* the same as the surface, but not *exactly* the same. It may rotate a tiny bit faster or slower -- and that's not apocalyptic, but it sure is interesting. sciencenews.org/article/earth-…#Earth#Core
You're about to hear a lot about #NuclearFusion. I've followed the field for years & can offer context. Top line:
- NIF's "breakeven" does not generate more power than it consumes
- NIF is not a model for a commercial fusion reactor
- This news is a big deal all the same. 1/n
Fusion researchers measure fusion output in "Q," the ratio of power produced to power needed to maintain the fusion plasma. NIF has exceeded Q=1.
Breakeven, right? Er, the accounting is not so simple, as Charles Seife explains. 2/n theatlantic.com/technology/arc…#fusion#NIF
The power that goes into igniting a fusion pellet is much less than the total amount that NIF consumes. "Breakeven" comes nowhere close to covering all of that consumption! A useful fusion power plant would require anything from Q=5 to Q=100. 3/n en.wikipedia.org/wiki/Fusion_en…#fusion
Twitter is full of "wonder science" accounts, many of them full of stolen images & misinformation. The recent viral tweet about the alleged void in space offers a good case study in how to spot the fakes. 1/5
Test #1: Who is sending the tweet? Reputable researchers, journalists, and institutions identify themselves. If the account is anonymous and contains no information, you should be suspicious. 2/5
Test #2: What is the source of the information? If there is no source/link (or a generic ID like "NASA"), that's a red flag. It's also a common tactic in bot accounts that scrape or steal images from the actual creators. 3/5
The true colors of the solar system, a short thread. * First, let's start with the Sun. Can we all agree it's white to the eye?
* inspired by James O’Donoghue & Marina Koren, with some color corrections by me.
Mercury is so gray that it's tough to tell whether you are seeing pictures of it in color or black-and-white. This one is true color, seriously. blogs.agu.org/wildwildscienc…
Venus reflects 70% of the sunlight that hits it, nearly as reflective as freshly fallen snow. So yeah, it is super-white, as you can tell just by looking at it in the sky. nasa.gov/mission_pages/…
Remember the "mystery hut" spotted by China's Yutu-2 rover on the far side of the Moon? Now we've seen it up close. Behold...a Moon rock. mp.weixin.qq.com/s/VgtehRidYL8-…
Reminder: When you apply a lot of imagination to an image at the very edge of resolution, you're going to "see" all kinds of strange things. The Face on Mars was a classic of this genre.
Fortunately, the universe is full of genuine mysteries. We still don't know for sure whether there is life on Mars!
I see versions of this nonsense claim all the time. This one went hugely viral. So let's dig into the actual numbers, cars versus volcanoes. (1/x)
Human activities released 33 billion tons of CO2 in 2019. About 16% of that, or 5 billion tons, is associated with road transportation. iea.org/articles/globa…
Calculating "every car in history" isn't easy, since car use has grown enormously over the past 120 years. Being extremely conservative, the total is 20 times this year's amount, or 100 billion tons. 3/x