Science & Technology


Mars used to be a lot wetter than it is now

© NASA/JPL-Caltech/University of Arizona
A high resolution digital terrain model (DTM) of an ancient river and tributaries on Mars as observed by the HiRISE camera on NASA's Mars Reconnaissance Orbiter (MRO).
Trying to understand the ancient climate of our own planet is hard enough, but to understand Mars' climatic history, planetary scientists have had to turn to a rather inventive method of climate forensics.

In case you didn't get the memo, Mars used to be a lot wetter than it is now; water flowed across its surface and vast lakes - or even seas - used to cover huge swathes of land. But as the red planet's atmosphere was stripped away by the solar wind, global air pressure plummeted, leaving Mars to freeze-dry. The liquid water froze into the crust and sublimated while any atmospheric moisture was lost to space.

However, the biggest puzzle for scientists isn't necessarily why Mars is now so dry now, but how it was able to sustain liquid water on its surface at all.
Blue Planet

Earth 2.0? Scientists discover Earth's "twin"

© Credit NASA Ames/SETI Institute/JPL-CalTech
An artist's concept of Kepler-186f, the first Earth-size planet found in the habitable zone, a range of distances from a star where liquid water could pool on an orbiting planet's surface
It is a bit bigger and somewhat colder, but a planet circling a star 500 light-years away is otherwise the closest match of our home world discovered so far, astronomers announced on Thursday.

The planet, known as Kepler 186f, named after NASA's Kepler planet-finding mission, which detected it, has a diameter of 8,700 miles, 10 percent wider than Earth, and its orbit lies within the "Goldilocks zone" of its star, Kepler 186 - not too hot, not too cold, where temperatures could allow for liquid water to flow at the surface, making it potentially hospitable for life.

"Kepler 186f is the first validated, Earth-size planet in the habitable zone of another star," Elisa V. Quintana of the SETI Institute and NASA's Ames Research Center in Mountain View, Calif., said at a news conference on Thursday. "It has the right size and is at the right distance to have properties similar to our home planet."
Blue Planet

What happens during a magnetic field reversal?

magnetic field
© unknown
The Earth's magnetic field protects life on Earth, shielding it from damaging radiation and moderating our climate. So the idea that it could completely flip around, or collapse altogether, should cause us to worry, right? Well, yes and no.

Magnetosphere Basics

The result of electrical currents generated deep within the Earth through dynamic action, the magnetosphere is a fluid force that is constantly changing in strength and orientation.

The Center of the Earth

The very heart of our planet is a solid inner core of mostly iron that is about the size of the moon. It is so hot (9000°F to 13000°F or about 5000°C to 7200°C) that its temperature equals that of the "surface" of the sun, but it remains solid because of the combined pressure of everything above it being pulled toward it by gravity.

Surrounding this solid inner core is a second layer made primarily of an iron-nickel alloy. Nearly as hot (7200°F to 9000°F or about 4000°C to 5000°C) but under a bit less pressure, this outer core is liquid.

The entire internet should be encrypted

© Getty Images
The Heartbleed bug crushed our faith in the secure web, but a world without the encryption software that Heartbleed exploited would be even worse. In fact, it's time for the web to take a good hard look at a new idea: encryption everywhere.

Most major websites use either the SSL or TLS protocol to protect your password or credit card information as it travels between your browser and their servers. Whenever you see that a site is using HTTPS, as opposed to HTTP, you know that SSL/TLS is being used. But only a few sites - like Facebook and Gmail - actually use HTTPS to protect all of their traffic as opposed to just passwords and payment details.

Many security experts - including Google's in-house search guru, Matt Cutts - think it's time to bring this style of encryption to the entire web. That means secure connections to everything from your bank site to to the online menu at your local pizza parlor.

Cutts runs Google's web spam team. He helps the company tweak its search engine algorithms to prioritize certain sites over others. For example, the search engine prioritizes sites that load quickly, and penalizes sites that copy - or "scrape" - text from others.

Methane emissions from fracking vastly underestimated by EPA - study

© AFP Photo / David McNew
The Environmental Protection Agency is under fire for underestimating the amount of methane gas emitted during natural gas operations, including fracking, thanks to a new study published in the Proceedings of the National Academy of Sciences (PNAS).

The study has 13 co-authors from several academic and research institutions, and used an aircraft to identify large sources of methane and quantify emission rates in southwestern Pennsylvania in June 2012. The authors discovered that emissions rates per second were 1,000 times higher than those estimated by the EPA for the same time period.

"Methane is the second most prevalent greenhouse gas emitted in the United States from human activities," the EPA website states. Carbon dioxide is the most prevalent, but it is not as damaging of a greenhouse gas as methane. "Pound for pound, the comparative impact of [methane] on climate change is over 20 times greater than [carbon dioxide] over a 100-year period."

Study: Even casual pot use causes brain abnormalities

© Shutterstock
Even casual use of marijuana can cause significant abnormalities in two areas of the brain that regulate emotion and motivation, according to a new study.

The findings, published Wednesday in the Journal of Neuroscience, challenge the idea that casual pot smoking is relatively harmless, researchers said.

The study, which was conducted by Northwestern Medicine and Massachusetts General Hospital/Harvard Medical School and funded in part by anti-drug government agencies, found major abnormalities directly related to the amount of weed smoked each week.

"Some of these people only used marijuana to get high once or twice a week," said the study's co-author, Dr. Hans Breiter. "People think a little recreational use shouldn't cause a problem, if someone is doing OK with work or school. Our data directly says this is not the case."
Fireball 4

Earth has experienced many more large-scale asteroid impacts over the past decade than previously thought

Chelyabinsk Meteorite
© Universe Today
The bolide that impacted the atmosphere over Chelyabinsk in Feb. 2013 detonated with the equivalent of 530 kilotons of TNT, injuring over 1,200 people.
This Earth Day, Tuesday, April 22, three former NASA astronauts will present new evidence that our planet has experienced many more large-scale asteroid impacts over the past decade than previously thought... three to ten times more, in fact. A new visualization of data from a nuclear weapons warning network, to be unveiled by B612 Foundation CEO Ed Lu during the evening event at Seattle's Museum of Flight, shows that "the only thing preventing a catastrophe from a 'city-killer' sized asteroid is blind luck."

Since 2001, 26 atomic-bomb-scale explosions have occurred in remote locations around the world, far from populated areas, made evident by a nuclear weapons test warning network. In a recent press release B612 Foundation CEO Ed Lu states:
"This network has detected 26 multi-kiloton explosions since 2001, all of which are due to asteroid impacts. It shows that asteroid impacts are NOT rare - but actually 3-10 times more common than we previously thought. The fact that none of these asteroid impacts shown in the video was detected in advance is proof that the only thing preventing a catastrophe from a 'city-killer' sized asteroid is blind luck. The goal of the B612 Sentinel mission is to find and track asteroids decades before they hit Earth, allowing us to easily deflect them."
The B612 Foundation is partnered with Ball Aerospace to build the Sentinel Infrared Space Telescope Mission.

Cosmic bloom? Early blossom for cherry tree after space trip

© AFP/Chujo-Hime-Seigan-Zakura Preservation Society
Cherry tree in bloom, grown from a cherry pit that spent time onboard the International Space Station (ISS), at the Ganjoji temple in Gifu city, central Japan.
A four-year-old cherry tree grown from a pit that orbited the Earth for eight months aboard the ISS has burst into blossom in Japan far earlier than usual with very interesting flowers, a riddle that is perplexing local scientists.

The 'extraterrestrial' cherry tree was expected to blossom in six years, in 2018, as normally it takes at least 10 years for similar sorts of tree to bear their first buds.

However, in April the 'space cherry tree', already grown to around 4 meters tall, suddenly produced nine flowers, reported local media. The blooms' form was also unusual as each had only five petals, while on the parent tree from which it was taken there were about 30 petals.

South Korea has the fastest internet service, U.S. runs dismal 26th worldwide

WLAN, Internet
© Deymos Photo/Shutterstock
Which county has the world's fastest Internet service? How about South Korea. That's according to a new study from content delivery service Pando Networks that sampled some 35 petabytes of data from 27 million downloads and 224 countries. The service found that South Korea is top in the world in terms of download speed, averaging 17.62 Mbps.

Romania has the second fastest Internet speeds on the planet, clocking in at 15.27 Mbps, and a trio of Eastern European countries round out the top five, Bulgaria, Lithuania and Latvia. The United States musters a very pedestrian 4.93 Mbps - good for 26th in the world - while China, home to the world's largest Internet population, manages a dismal 1.96 Mbps.

Glow in the dark road unveiled in the Netherlands

glow in the dark road
© AFP/Getty
These "glowing lines" could replace street lights or be used in areas where there are none.
Glow in the dark road markings have been unveiled on a 500m stretch of highway in the Netherlands.

The paint contains a "photo-luminising" powder that charges up in the daytime and slowly releases a green glow at night, doing away with the need for streetlights.

Interactive artist Daan Roosegaarde teamed up with Dutch civil engineering firm Heijmans to work on the idea.

The technology is being tested with an official launch due later this month.

It is the first time "glowing lines" technology has been piloted on the road and can be seen on the N329 in Oss, approximately 100km south east of Amsterdam.

Once the paint has absorbed daylight it can glow for up to eight hours in the dark.