Herds of wooly mammoths once shook Earth beneath their feet, sending humans scurrying across the landscape of prehistoric Ohio. But then something much larger shook Earth itself, and at that point these mega mammals' days were numbered.
Something -- global-scale combustion caused by a comet scraping our planet's atmosphere or a meteorite slamming into its surface -- scorched the air, melted bedrock and altered the course of Earth's history. Exactly what it was is unclear, but this event jump-started what Kenneth Tankersley, an assistant professor of anthropology and geology at the University of Cincinnati, calls the last gasp of the last ice age.

"Imagine living in a time when you look outside and there are elephants walking around in Cincinnati," Tankersley says. "But by the time you're at the end of your years, there are no more elephants. It happens within your lifetime."

Tankersley explains what he and a team of international researchers found may have caused this catastrophic event in Earth's history in their research, "Evidence for Deposition of 10 Million Tonnes of Impact Spherules Across Four Continents 12,800 Years Ago," which was published in the Proceedings of the National Academy of Sciences.

This research might indicate that it wasn't the cosmic collision that extinguished the mammoths and other species, Tankersley says, but the drastic change to their environment.

"The climate changed rapidly and profoundly. And coinciding with this very rapid global climate change was mass extinctions."

London - Scientists believe they have found the first evidence that other universes exist after analysing the data gathered by the European Space Agency's Planck spacecraft.

Theories that our universe could be just one of billions -- perhaps an infinite number - have been discussed for decades but until now they have lacked any evidence.

However, a few weeks ago, scientists published a new map of the cosmic microwave background - the 'radiation' left behind after the Big Bang that created the universe 13.8 billion years ago.

The map, based on Planck data, showed anomalies in the background radiation that, some experts say, could only have been caused by the gravitational pull of other universes outside our own, The Sunday Times reported.

"These anomalies were caused by other universes pulling on our universe as it formed during the Big Bang," said Laura Mersini-Houghton, a theoretical physicist at the University of North Carolina at Chapel Hill.

A Lake Tahoe area scientist has found an unidentified life form in a high-altitude lake. Now agencies in the area are trying to figure out what it is.

University of Nevada Reno Professor Emeritus, John Kleppe pilots a remotely operated vehicle, or "ROV," into the frigid depths of Fallen Leaf Lake near Lake Tahoe. Particles whiz by the ROV's lights like stars.

"It is sort of amazing because when you think about it no humans have seen a lot of what we see. It is like walking on the moon," said Kleppe.

He discovered a 3-thousand-year-old hidden forest still standing. He says it's evidence of past mega droughts. As if that's not strange enough, he has found something living in the forest.

"What we are seeing here is a thing, which is like a balloon of green jell and it will eventually look like a baggie and then like it is creating a gas in it and then float away," said Kleppe.

Astronomers have found a group of comets that have risen from the dead.

The asteroidal belt comets - or ABCs for short - lie in the main asteroid belt between Mars and Jupiter, report astronomers on the on the pre press website ArXiv.org.

Dr Ignacio Ferrin, Dr Jorge Zuluaga and Pablo Cuartas from Columbia's University of Antioquia, say the group of eleven objects behave like comets, but have asteroidal orbits.

They propose the objects they've dubbed 'Lazarus comets' are extinct comets that have been rejuvenated when their orbits changed.

"The asteroidal belt contains an enormous graveyard of ancient dormant and extinct rocky comets, that [are rejuvenated], in response to a diminution of their perihelion distance [closest orbital position to the Sun]," the authors write.

The findings, which are accepted for publication in the Monthly Notices of the Royal Astronomical Society, blurs the line between comets and asteroids.

Comets become dormant when they no longer emit volatile gases - they are then called asteroids. But previous research has shown these dormant comets can be rejuvenated into comets after collisions with asteroids, meteors or other comets, as well as high energy particle impacts.

Ferrin and colleagues now suggest a new comet rejuvenation theory.

Individuals who learn two languages at an early age seem to switch back and forth between separate "sound systems" for each language, according to new research conducted at the University of Arizona.

The research, to be published in a forthcoming issue of Psychological Science, a journal of the Association for Psychological Science, addresses enduring questions in bilingual studies about how bilingual speakers hear and process sound in two different languages.

"A lot of research has shown that bilinguals are pretty good at accommodating speech variation across languages, but there's been a debate as to how," said lead author Kalim Gonzales, a psychology doctoral student at the University of Arizona. "There are two views: One is that bilinguals have different processing modes for their two languages -- they have a mode for processing speech in one language and then a mode for processing speech in the other language. Another view is that bilinguals just adjust to speech variation by recalibrating to the unique acoustic properties of each language."

The Latest On The CLOUD Experiment at CERN By Sebastian Lüning and Fritz Vahrenholt

On May 10, 2013, at the online Austrian ORF, there was a rare interview with the CLOUD Experiment director of the European Organization for Nuclear Research, Jasper Kirkby. Within the scope of the CLOUD project, it is being investigated to what extent solar activity has on cloud formation via the mechanism of cosmic radiation and the impact this could have on the Earth's climate (see Chapter 6 of our book Die kalte Sonne).

Here's an excerpt of the worthwhile interview:

In April, when the Hubble Space Telescope looked out towards Jupiter's orbit and observed what has been billed as the "Comet of the Century" - Comet C/2012 S1 ISON - the space telescope photographed a unique feature in the comet's coma. Now, a team of ground-based astronomers have performed follow-up observations, imaging Comet ISON as it heads towards the Sun and was just outside the orbit of Mars.

They, too, have seen this unique feature, which is thought to be a jet blasting dust particles off the sunward-facing side of the comet's nucleus. These very useful follow-up observations are providing more insight on this highly anticipated comet, as well as helping to predict what might happen it makes its closest approach to the Sun in November 2013.

Comet C/2012 S1 (ISON) was discovered on September 21, 2012 by Vitali Nevski and Artyom Novichonok on CCD images obtained with a 0.4-m f/3 Santel reflector of the International Scientific Optical Network (ISON) near Kislovodsk, Russia.

Comet C/2012 S1 (ISON) will get to within 0.012AU of the Sun (extremely close) at the end of November 2013 and then to ~0.4AU from Earth at the end of December 2013! According to its orbit, this comet might become a naked-eye object in the period November 2013 - January 2014. And it might reach a negative magnitude at the end of November 2013. For more info about the discovery please see our previous post here. While here & here you can read our October 2012 updates about comet ISON.

Our Team working with a suite of Hubble sized telescopes in Australia, Hawaii and the Canary Islands is collaborating with a range of professional scientists in an attempt to get high spatial resolution data on comet C/2012 S1 (ISON). Supported by the Liverpool John Moores Astrophysics Research Institute and the Faulkes Telescope Project we have been imaging C/2012 S1 ISON since the day it was discovered, being part of the discovery MPEC for the comet ourselves.

Last Monday, May 13, the Suomi NPP satellite captured a fascinating image of Tropical Cyclone Mahasen as it moved northeast over the Bay of Bengal. The clouds of the storm itself weren't optically visible in the darkness of a nearly new Moon, but lightning flashes within it were... as well as the eerie ripples of atmospheric gravity waves spreading outwards from its center.

According to the Space Physics Research Group at the University of California, Berkeley:

Gravity waves are the oscillations of air parcels by the lifting force of bouyancy and the restoring force of gravity. These waves propagate vertically as well as horizontally, and actively transport energy and momentum from the troposphere to the middle and upper atmosphere. Gravity waves are caused by a variety of sources, including the passage of wind across terrestrial landforms, interaction at the velocity shear of the polar jet stream and radiation incident from space. They are found to affect atmospheric tides in the middle atmosphere and terrestrial weather in the lower atmosphere. (Source)

Atmospheric gravity waves aren't to be confused with gravitational waves in space, which are created by very dense, massive objects (like white dwarf stars or black holes) orbiting each other closely.

Infinity down, only 69,999,997 to go.

New research has proven that prime numbers don't just disappear as numbers get larger - instead, there is an infinite number of prime numbers separated by a distance of at most 70 million.

The new proof, accepted this month for publication in the journal Annals of Mathematics, takes the field one step closer to solving the twin prime conjecture, a famous mathematical idea that suggests the existence of an infinite number of prime numbers separated by a distance of 2 (for example, the prime numbers 11 and 13, which are separated by 2). Prime numbers are those that are divisible by only themselves and 1.

Prior to this discovery, mathematicians suspected there were infinitely many twin primes, or prime numbers separated by two, but proofs hadn't set bounds on how far apart primes could be separated. [The 9 Most Massive Numbers in Existence]

"It's a huge step forward in terms of showing that there are primes close together," said Daniel Goldston, a mathematician at San Jose State University in California. "It's a big huge step toward the twin prime conjecture."