Archives par mot-clé : Technology

Visualizing All of Earth’s Satellites: Who Owns Our Orbit?

by T. Wood, Oct 20, 2020 in VisualCapitalist

Visualizing All of Earth’s Satellites

For centuries, humans have looked to space and the stars for answers. The fascination is more than philosophical—it’s coupled with the need to solve problems here on Earth.

Today, there are seemingly countless benefits and applications of space technology. Satellites, for instance, are becoming critical for everything from internet connectivity and precision agriculture, to border security and archaeological study.

Space is Open for Business

Right now, there are nearly 6,000 satellites circling our tiny planet. About 60% of those are defunct satellites—space junk—and roughly 40% are operational.

As highlighted in the chart above, The Union of Concerned Scientists (UCS), determined that 2,666 operational satellites circled the globe in April of 2020.

Over the coming decade, it’s estimated by Euroconsult that 990 satellites will be launched every year. This means that by 2028, there could be 15,000 satellites in orbit.

New technology promises to be game-changer in the extraction of rare earths

by V.L. Leotaud, May 10, 2020 in MiningCom

Researchers at Purdue University in the US have developed a new technology that promises to be a game-changer in the extraction of rare earths.


In a paper published in the journal Green Chemistry, the scientists explain that the patented extraction and purifying processes use ligand-assisted chromatography and are shown to remove and purify rare earth metals from coal ash, recycled magnets and raw ore safely, efficiently and with virtually no detrimental environmental impact.

This is key because, at present, many companies across the world don’t even dare to consider extracting REE due to the damages caused to the environment by acid-based separation and purification of these elements.

“About 60% of rare earth metals are used in magnets that are needed in almost everyone’s daily lives. These metals are used in electronics, aeroplanes, hybrid cars and even windmills,” Nien-Hwa Linda Wang, whose lab developed the technology, said in a media statement. “We currently have one dominant foreign source for these metals and if the supply were to be limited for any reason, it would be devastating to people’s lives. It’s not that the resource isn’t available in the US, but that we need a better, cleaner way to process these rare earth metals.”

Neodymium magnets. (Image by Nevit Dilmen, Wikimedia Commons).

See also Two-zone ligand-assisted displacement chromatography for producing high-purity praseodymium, neodymium, and dysprosium with high yield and high productivity from crude mixtures derived from waste magnets (here)

Negative CO2 Emissions

by Kevin Kilty, January 24, 2020 in WUWT

An article in the January 2020 Issue of Physics Today (1) presents an interesting and very readable overview of methods to capture and store away CO2 emissions. The purpose of this guest blog is to summarize a few key points the paper makes, and add some commentary. WUWT has covered some of this same territory recently here and here.


Of course, the motivation for negative emissions technologies (NETs), or CO2 capture, is to bring atmospheric CO2 back to safe levels. Although the article fails to mention what safe means in this context, and what levels are unsafe, it alludes to melting polar ice and methane escaping from melting permafrost as consequences of unsafe climate. Nothing unusual here. Despite relegating its case for an unsafe future to such enterprises as the IPCC, the article does provide some insight into the cause of what seems to be the current “crisis” mentality. It is 1.5°C temperature rise goal of the 2015 Paris agreement. As readers of WUWT already know, this is not a 1.5°C increase from now, but rather from an estimated pre-industrial level — meaning that two-thirds of that margin is already gone and we have but 0.5°C left to work with. I suspect most people do not understand this subtle point.

Eventually the article makes a brief excursion into more phenomena by which climate change would become unsafe — forest fires, droughts, and sea level rise. All of this is also familiar to WUWT readers.

Technologies Involved