The surprising discovery of asteroids with comet tails supports the longstanding claim of the electrical theorists - that the essential difference between asteroids and comets is the shape of their orbits.

According to a recent story in USA Today, astronomers are "rethinking long-held beliefs about the distant domains of comets and asteroids, abodes they've always considered light-years apart". The discovery has forced astronomers to speculate that some asteroids are actually "dirty snowballs in disguise".

For many years the standard view of asteroids asserted that they are composed of dust, rock, and metal and that most occupy a belt between Mars and Jupiter. In contrast, comets were claimed to arrive from a home in deep space, most coming from an imagined "Oort Cloud" at the outermost reaches of the solar system, where they are supposed to have accreted from leftover dust and ices from the formation of the solar system.

But now, "the locales of comets and asteroids may not be such a key distinction", states Dan Vergano, reporting on the work of two University of Hawaii astronomers, Henry Hsieh and David Jewitt. In a survey of 300 asteroids lurking in the asteroid belt, the astronomers detected three objects that "look a lot like comets ... ejecting little comet tails at times from their surfaces". The three red circles in the illustration above describe the orbits of these bodies.

Asteroids, unlike comets, are seldom seen sporting a tail as they orbit the sun, but Spanish astronomers say they've observed one of these rare exceptions.

Using a telescope in the Canary Islands, they spotted an asteroid dubbed P/2012 F5 that displayed a trail like that of comets.

Its emission of dust or gas may have been caused by internal rupture or collision with another asteroid, a release from the Spanish Foundation for Science and Technology reported Wednesday.

"Our models indicate that [the trail] was caused by an impulsive short-lived event lasting just a few hours around the July 1st, 2011, with an uncertainty of 20 days," Fernando Moreno, researcher at the Astrophysics Institute of Andalusia said.

The recent explosion of a large meteor over Russia caused hundreds of injuries and considerable damage to local buildings - the most destructive such event in more than 100 years. The explosion has also raised new questions pointing directly to the behavior of large meteors in the Electric Universe.

A colossal sunspot on the surface of the sun is large enough to swallow six Earths whole, and could trigger solar flares this week, NASA scientists say.

The giant sunspot was captured on camera by NASA's Solar Dynamics Observatory as it swelled to enormous proportions over the 48 hours spanning Tuesday and Wednesday (Feb. 19 and 20). SDO is one of several spacecraft that constantly monitor the sun's space weather environment.

"It has grown to over six Earth diameters across, but its full extent is hard to judge since the spot lies on a sphere, not a flat disk," wrote NASA spokeswoman Karen Fox, of the agency's Goddard Space Flight Center in Greenbelt, Md., in an image description.

Flowers may be silent, but scientists have just discovered that electric fields allow them to communicate with bumblebees and possibly other species, including humans.

It's well known that color, shape, pattern and fragrances allow flowers to connect with pollinators, but the new study, published in the journal Science, adds electricity to this already impressive lineup.

"We just now have discovered that electrical potentials, an unavoidable by-product of flying in air for bumblebees and being grounded for the flower, is being exploited to benefit both parties," co-author Daniel Robert told Discovery News. It's "another example of the beauty of evolution," added Robert, a professor in the University of Bristol's School of Biological Sciences.

He explained that bees have a positive electrical charge because they fly in air, which is full of all kinds of tiny particles, such as dust and charged molecules. Friction from these particles causes bees to lose electrons, leaving bumblebees positively charged.

Flowers, on the other hand, "are electrically connected to ground," he said. Unlike copper wire, which transfers charges very quickly, plants conduct electricity very slowly and tend to possess a negative charge.

Researchers at Cornell University have managed to fabricate a bioengineered human ear that looks and acts like a natural one. They hope to be able to give children with a rare congenital ear deformity a new, 3-D printed ear that's specifically tailored to fit them.

Children with microtia are born with a deformed or missing external ear, sometimes without even an ear opening. Although they can have a fully-formed inner ear, it's difficult for them to hear without the external structure to direct sound, to say nothing of the psychological impact of having a prominently visible deformity. Typically, treatment for microtia involves multiple surgeries over several months or years, often using cartilage from the child's ribcage.

There are many drawbacks to this approach, including a limited supply of cartilage that can be taken and complications that occur at the site where it's harvested from. Scientists have long been looking for a way to engineer new tissue for reconstruction, but previous attempts at bioengineered ears lost their shape over time or the cells within them died.

Over three months of observation, Cornell researchers found that their 3-D printed ear was more flexible and longer-lasting than other bioengineered ears. Using 3-D printing also would allow them to mimic the normal anatomy of the patient's ear, since children with microtia usually only have deformities on one side.

"Predicted population increases in this century can be expected to translate into more people dying from earthquakes. There will be more individual earthquakes with very large death tolls as well as more people dying during earthquakes than ever before, according to a newly published study led by U.S. Geological Survey engineering geologist Thomas L. Holzer."

Holzer and his USGS coauthor James Savage studied earthquakes with death tolls of more than 50,000, which they define as catastrophic, and reported global death tolls from roughly 1500 A.D. to the present. Comparing those events to estimates of world population, they found that the number of catastrophic earthquakes has increased as population has grown. After statistically correlating the number of catastrophic earthquakes in each century with world population, they were able to use new (2011) 21st-century population projections by the United Nations to project that approximately 21 catastrophic earthquakes will occur in the 21st century, a tripling of the seven that occurred in the 20th century. They also predict that total deaths in the century could more than double to approximately 3.5 million people if world population grows to 10.1 billion by 2100 from 6.1 billion in 2000.

"This prediction need not be a prophesy: the National Earthquake Hazard Reduction Program (NEHRP) in the U.S. can be a model for how science can inform engineering designs that are adopted into life-saving building codes in earthquake-prone regions," said USGS Associate Director for Natural Hazards David Applegate. "I also cannot stress enough the value of educated citizens - those who understand the natural hazards of this planet and are empowered to take action to reduce their risk."

Four catastrophic earthquakes have already struck since the beginning of the 21st century, including the 2004 Sumatra-Andaman earthquake (and tsunami) and 2010 Haiti earthquake that each may have killed over 200,000 people. The study explains this increase in lethal earthquakes. It is not that we are having more earthquakes; it is that more people are living in seismically vulnerable buildings in the world's earthquake zones.

Today, I wrote a story about a mysterious explosion over Melrose in 1954 that shattered windows, cracked ceilings, and caused a local panic that seemed to echo what happened in Chelyabinsk, Russia last week.

The Globe wrote three stories at the time, each asserting that the pressure wave that led 200 people to swarm the Melrose fire station was caused by several airplanes breaking the sound barrier while flying too close to the ground.

But readers have questions about whether, technologically speaking, that could be the case. Steve Smith, an aviation buff, wrote in an e-mail that aircraft of the time were technologically incapable of breaking the sound barrier.

Smith wrote:

"In 1954 the United States had 2 aircraft in service that might be doing formation flying over land, the Lockheed P80 Shooting Star and the North American F86 Sabre. We also had some naval variants, such as the F9F Panther and Cougar. The first aircraft that could break mach-1 in level flight was the North American F100 super-sabre, but that didn't happen until some time in 1957 and only as a test aircraft.

All these aircraft were incapable of exceeding the speed of sound at the time. Some rocket plane testing in the west did exceed the Mach 1, perhaps Chuck Yeager and the Bell X-1 comes to mind."

Bottlenose dolphins call out the specific names of loved ones when they become separated, a study finds.

Other than humans, the dolphins are the only animals known to do this, according to the study, published in the latest Proceedings of the Royal Society B. The big difference with bottlenose dolphins is that these communications consist of whistles, not words.

Earlier research found that bottlenose dolphins name themselves, with dolphins having a "signature whistle" that encodes other information. It would be somewhat like a human shouting, "Hey everybody! I'm an adult healthy male named George, and I mean you no harm!"

The new finding is that bottlenose dolphins also say the names of certain other dolphins.

"Animals produced copies when they were separated from a close associate and this supports our belief that dolphins copy another animal's signature whistle when they want to reunite with that specific individual," lead author Stephanie King of the University of St. Andrews Sea Mammal Research Unit told Discovery News.