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Member since: Tue Feb 10, 2004, 01:08 PM
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Environmental Scientist

Journal Archives

James Webb's mirror is revealed

Revealed for the first time in all its glory - the main mirror of the James Webb Space Telescope, which will be launched in 2018.

JWST is regarded as the successor to Hubble, and will carry technologies capable of detecting the light from the first stars to shine in the Universe.

Paramount in that quest will be a large primary reflecting surface.

And with a width of 6.5m, JWST's will have roughly seven times the light-collecting area of Hubble's mirror.

It is so big in fact that it must be capable of folding. Only by turning the edges inwards will the beryllium segments fit inside the telescope's launch rocket.


Titan’s great lakes appear to be filled with clear, colorless methane

Liquid seas exist on the surface of just two worlds in the Solar System: Earth and Saturn's moon Titan. Discovered by NASA's Cassini spacecraft about a decade ago, the hydrocarbon seas of Titan are more exotic, of course, as they exist in liquid form at temperatures around -180 degrees Celsius.

Now, after the Cassini spacecraft has made a number of flybys of Titan, scientists assessing light and other radiation emanating from the moon's surface say they have a better handle on exactly what is in one of those seas. And to their surprise, they have found that the second largest lake on Titan, Ligeia Mare, is composed of nearly pure methane.

“We expected to find that Ligeia Mare would be mostly ethane, which is produced in abundance in the atmosphere when sunlight breaks methane molecules apart,” said Alice Le Gall, lead author of the new study. “Instead, this sea is predominantly made of pure methane."

Further analysis of the data, which assessed the transparency of the sea, indicated that this methane extends to a depth of about 160 meters in some locations, down to a sludge layer atop the moon's crust. This combination of sea and seafloor suggests that in Titan's atmosphere, nitrogen and methane react to form organic molecules, which then fall to the surface as a methane rain. The heaviest of these molecules, such as benzene, sink to the bottom of the sea.

Were you to boat upon Titan, then, you might gaze down into a clear, deep sea. Instead of being colored blue like Earth's oceans, however, these clear seas would bear the yellowish and orangish hues of Titan's skies. And might anything live in those oceans? It's a tantalizing possibility to consider.


Mars’ surface revealed in unprecedented detail

26 April 2016

The surface of Mars – including the location of Beagle-2 – has been shown in unprecedented detail by UCL scientists using a revolutionary image stacking and matching technique.

Exciting pictures of the Beagle-2 lander, the ancient lakebeds discovered by NASA’s Curiosity rover, NASA’s MER-A rover tracks and Home Plate’s rocks have been released by the UCL researchers who stacked and matched images taken from orbit, to reveal objects at a resolution up to five times greater than previously achieved.

A paper describing the technique, called Super-Resolution Restoration (SRR), was published in Planetary and Space Science in February but has only recently been used to focus on specific objects on Mars. The technique could be used to search for other artefacts from past failed landings as well as identify safe landing locations for future rover missions. It will also allow scientists to explore vastly more terrain than is possible with a single rover.

Co-author Professor Jan-Peter Muller from the UCL Mullard Space Science Laboratory, said: “We now have the equivalent of drone-eye vision anywhere on the surface of Mars where there are enough clear repeat pictures. It allows us to see objects in much sharper focus from orbit than ever before and the picture quality is comparable to that obtained from landers.

“As more pictures are collected, we will see increasing evidence of the kind we have only seen from the three successful rover missions to date. This will be a game-changer and the start of a new era in planetary exploration.”

- See more at: https://www.ucl.ac.uk/news/news-articles/0416/260416-Mars-images#sthash.UlFIOwHl.dpuf

Hubble Discovers Moon Orbiting the Dwarf Planet Makemake

Newswise — Peering to the outskirts of our solar system, NASA's Hubble Space Telescope has spotted a small, dark moon orbiting Makemake, the second brightest icy dwarf planet -- after Pluto -- in the Kuiper Belt.

The moon -- provisionally designated S/2015 (136472) 1 and nicknamed MK 2 -- is more than 1,300 times fainter than Makemake. MK 2 was seen approximately 13,000 miles from the dwarf planet, and its diameter is estimated to be 100 miles across. Makemake is 870 miles wide. The dwarf planet, discovered in 2005, is named for a creation deity of the Rapa Nui people of Easter Island.

The Kuiper Belt is a vast reservoir of leftover frozen material from the construction of our solar system 4.5 billion years ago and home to several dwarf planets. Some of these worlds have known satellites, but this is the first discovery of a companion object to Makemake. Makemake is one of five dwarf planets recognized by the International Astronomical Union.

The observations were made in April 2015 with Hubble's Wide Field Camera 3. Hubble's unique ability to see faint objects near bright ones, together with its sharp resolution, allowed astronomers to pluck out the moon from Makemake's glare. The discovery was announced today in a Minor Planet Electronic Circular.


Despite their small brains ravens and crows are just as clever as chimps

A study led by researchers at Lund University in Sweden shows that ravens are as clever as chimpanzees, despite having much smaller brains, indicating that rather than the size of the brain, the neuronal density and the structure of the birds' brains play an important role in terms of their intelligence.

"Absolute brain size is not the whole story. We found that corvid birds performed as well as great apes, despite having much smaller brains," says Can Kabadayi, doctoral student in Cognitive Science.

Intelligence is difficult to test, but one aspect of being clever is inhibitory control, and the ability to override animal impulses and choose a more rational behaviour. Researchers at Duke University, USA, conducted a large-scale study in 2014, where they compared the inhibitory control of 36 different animal species, mainly primates and apes. The team used the established cylinder test, where food is placed in a transparent tube with openings on both sides. The challenge for the animal is to retrieve the food using the side openings, instead of trying to reach for it directly. To succeed, the animal has to show constraint and choose a more efficient strategy for obtaining the food.

The large-scale study concluded that great apes performed the best, and that absolute brain size appeared to be key when it comes to intelligence. However, they didn't conduct the cylinder test on corvid birds.


And both are smarter than the Donald....

White House says it will offer largest military package in US history

Source: Ynetnews, Reuters

The United States plans to offer Israel the largest military assistance package in US history, according to an Obama administration official.

"We are prepared to sign an MOU (memorandum of understanding) with Israel that would constitute the largest single pledge of military assistance to any country in US history," a White House official told Reuters.

The statement came hours after 83 US senators sent a letter to President Obama, urging him to reach a military assistance deal with Israel.

"In light of Israel's dramatically rising defense challenges, we stand ready to support a substantially enhanced new long-term agreement to help provide Israel the resources it requires to defend itself and preserve its qualitative military edge," said the letter.

Read more: http://www.ynetnews.com/articles/0,7340,L-4796369,00.html

Snyder, Schuette: No Right For Local Voters to Choose Their Leaders

Voters don’t have a constitutional right to choose their local government leaders. That’s a central argument used by lawyers for state Attorney General Bill Schuette and Gov. Rick Snyder as they defend the state’s emergency manager law against a federal lawsuit.

The state’s response to the lawsuit was filed earlier this month. The lawsuit says the statute that allowed the state takeover of cities like Detroit and Flint violates the rights of local voters. And that it discriminates based on race and on wealth.

The state is asking the U.S. Sixth Circuit Court of Appeals to toss the lawsuit because the U.S. Constitution guarantees voters’ rights to elect their state officials — but, they argue, it doesn’t offer the same promises when it comes to local governments.

Both sides are waiting to hear if the federal appeals court will call them in for oral arguments later this year.


Tuesday Toon Roundup 2: The Rest










Tuesday Toon Roundup 1- Gotta Stop Him!

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