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PostPosted: Sat Feb 29, 2020 1:02 pm 
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I don't think I made one, and I cannae find it if I did.

The Earth Formed Much Faster than Previously Thought

https://www.astrowatch.net/2020/02/the- ... -than.html

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PostPosted: Mon Mar 02, 2020 5:44 pm 
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Earth may have been a 'water world' 3bn years ago, scientists find

https://www.theguardian.com/science/202 ... tists-find

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PostPosted: Tue Mar 10, 2020 4:58 pm 
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Days Were Half An Hour Shorter 70 million Years Ago

https://www.ancient-origins.net/news-ge ... ys-0013395

In similar news from four years ago:

How Ancient Coral Revealed the Changing Length of a Year

https://www.theatlantic.com/science/arc ... ay/471180/

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PostPosted: Thu Apr 02, 2020 5:34 pm 
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Star Gazing at Cheomseongdae - East Asia’s Oldest Observatory

https://www.ancient-origins.net/human-o ... ae-0013505

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PostPosted: Thu Apr 09, 2020 4:24 pm 
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Himalayas Seen from India for the First Time in 30 Years Due to Air Pollution Drop

https://www.coasttocoastam.com/article/ ... ution_drop

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PostPosted: Sun May 03, 2020 1:13 pm 
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Researchers Discover Different Types of Aurora Borealis

https://now.northropgrumman.com/researc ... -borealis/

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PostPosted: Sun Jun 28, 2020 3:10 pm 
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A new paper submitted to Nature concerns the terrestrial uranium isotope cycle.

Quote:
Changing conditions on the Earth’s surface can have a remarkable influence on the composition of its overwhelmingly more massive interior. The global distribution of uranium is a notable example. In early Earth history, the continental crust was enriched in uranium. Yet after the initial rise in atmospheric oxygen, about 2.4 billion years ago, the aqueous mobility of oxidized uranium resulted in its significant transport to the oceans and, ultimately, by means of subduction, back to the mantle. Here we explore the isotopic characteristics of this global uranium cycle. We show that the subducted flŭ of uranium is isotopically distinct, with high 238U/235U ratios, as a result of alteration processes at the bottom of an oxic ocean. We also find that mid-ocean-ridge basalts (MORBs) have 238U/235U ratios higher than does the bulk Earth, confirming the widespread pollution of the upper mantle with this recycled uranium. Although many ocean island basalts (OIBs) are argued to contain a recycled component, their uranium isotopic compositions do not differ from those of the bulk Earth. Because subducted uranium was probably isotopically unfractionated before full oceanic oxidation, about 600 million years ago, this observation reflects the greater antiquity of OIB sources. Elemental and isotope systematics of uranium in OIBs are strikingly consistent with previous OIB lead model ages, indicating that these mantle reservoirs formed between 2.4 and 1.8 billion years ago. In contrast, the uranium isotopic composition of MORB requires the convective stirring of recycled uranium throughout the upper mantle within the past 600 million years.


A little background on the topic can be found on this blog post:
Uranium: The story beneath Earth’s crust https://ontherocksgeoblog.wordpress.com ... hs-mantle/

Here's the open-access version of the terrestrial uranium isotope cycle:
http://digitalcommons.uri.edu/cgi/viewc ... gsofacpubs

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PostPosted: Tue Aug 18, 2020 7:41 pm 
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The Earth's magnetic field protects us from the Sun's charged particles. However, there is a large region in the Earth's atmosphere where the magnetic field is significantly lower. This phenomenon is known as the South Atlantic Anomaly and can adversely affect the operations of satellites and spacecraft. Read more about it here:

https://www.sciencealert.com/nasa-is-tr ... etic-field

Thanks to Greg Barr for this link.

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