Georgia Tech student Alexandra Gaigelas takes a shuttle bus to get around the Atlanta campus. Many times, she waits too long for a bus.

"There's nothing more frustrating than standing at a stop, waiting for 10 minutes, getting on the bus and seeing another bus directly behind you.”

And that second bus is largely empty. It's called bus bunching, and it happens when buses are thrown off schedule because of traffic, weather or too many passengers at one stop.

And when those buses are off schedule, the drivers try to adjust. Student Sukirat Bakshi says he's been victim of a bus "drive-by."

“It happened to me where the driver just would not stop at a stop. They would just run off to catch up to the schedule.”

It turns out math can fix the problem. Georgia Tech professor John Bartholdi and University of Chicago professor Donald Eisenstein used complex algebra to develop a kind of anti-bus-bunching formula. They took what’s known as the Markov Chain through the wringer. It’s a math theory that shows predictable long-term behavior.

“The trick is to hold the bus for an adjustable amount of time at one stop,” Bartholdi said. “We simply control how long they wait at the end of the route, and then we tell them, 'drive comfortable with the traffic to the other end. Don’t worry about where you are. Just flow with the traffic.' "

Buses in the loop are all connected through GPS and a computer pad. It signals to the driver when it’s time to leave. Georgia Tech is testing the theory on its shuttle system.

“This tells me exactly when it’s time to go, and the communication between each other is done automatically, so it takes a lot of stress from us,” said Clarence July, who drives one of the gold and yellow Georgia Tech buses.

Drivers can ignore the schedule, and riders on campus can walk up to any stop and know that a bus will come within approximately six minutes. Bartholdi and Eisenstein say their math formula works for any shuttle system that runs in a loop in which buses are no more than about 12 to 15 minutes apart.

“Others have tried to control buses by asking drivers to try to adhere to a target schedule,” Bartholdi said. “What is new here is that the buses in effect coordinate themselves. No one needs to tell the drivers what to do; no one needs to worry about being off-schedule or how to recover a lost schedule.”

Georgia Tech plans to fully implement the no schedule bus system on campus this fall.

Here's how Bartholdi explains the equations used to calculate the space between buses:

This equation is actually a bunch of equations: one for each bus. The first line describes how the headway (the space between buses) changes for the bus that is currently at the end of the route (the turnaround point). Alpha (in red) is a control parameter - a number, say, 0.5 - by which the bus manager chooses whether the bus should wait longer (and fix imbalances faster) or vice versa. The "v" is the average velocity of the buses.

The second line describes how the headways of the other buses change.

This collection of equations describes how the headways change from bus arrival t to the next bus arrival t+1. In other words, it predicts the future behavior of all the buses.

Don Eisenstein and I recognized that this set of equations has a very special algebraic structure: they describe a "Markov Chain," which is a sequence of events for which the future can be predicted by knowing merely the current state (no history is needed). In our case, we only need to know the most recent headways to predict the next headways, and the headways after those, and so on.

The theory of Markov Chains allows us to conclude that, in the absence of disruptions, the headways will move inexorably and quickly toward a common value, which is given in the equation above. What this means in practice is that the buses will move away from each other, to space themselves more evenly. In other words, we will have created a force, a sort of "anti-gravity” that pushes the buses apart and so resists bunching.

(CNNMéxico) - On Sunday, May 20, an annular solar eclipse will be visible from some areas of United States, northern Mexico and Canada, according to the Institute of Astronomy, in the Universidad Nacional Autónoma de México (UNAM, Autonomous National University of Mexico).

"Solar eclipses occur when the moon covers the solar disk and projects its shadow on Earth," the Institute explained on its website.

A solar eclipse happens when the moon is in its new moon phase and is perfectly aligned with both the sun and the Earth. From our perspective, the sun is hidden.

During the astronomical phenomenon on May 20, the moon will be in one of its furthest positions from Earth, so its shadow will not be able to completely hide the sun, as would occur in a total eclipse.

That's why this phenomenon is called an annular eclipse. "For this beautiful phenomenon, the sun peeks over the edges of the moon as a bright shining ring," according to the Institute.

"In the United States, the afternoon sun will become a luminous ring in places such as Medford, Oregon; Chico, California; Reno, Nevada; St. George, Utah; Albuquerque, New Mexico, and Lubbock, Texas," according to NASA.
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There are three more men in space Tuesday than there were 24 hours ago. Monday night at 11:01 p.m. EDT, the remaining three members of the Expedition 31 crew launched aboard the Soyuz spacecraft and are now on their way to the International Space Station.

NASA astronaut Joe Acaba (@AstroAcaba), as well as Russian cosmonauts Gennady Padalka and Sergei Revin will join commander Oleg Kononenko and flight engineers Don Pettit (@Astro_Pettit) and Andre Kuipers, who are already aboard the ISS.

Monday night's launch, from Baikonur Cosmodrome in Kazakhstan, was preceded by the usual pre-launch activities:  the crew signed the door of their crew quarters, were blessed by a Russian Orthodox priest, and said goodbye to their families before getting their suits checked and boarding the spacecraft.

Onboard with the three men, acting as this flight's talisman, was a stuffed Smokey Bear. Traditionally, Soyuz crews fly with a small toy hanging from the top of the crew compartment that acts as a gravity indicator: when the toy floats, the crew's in orbit. (Once it was an Angry Bird!)

If you missed it (or if you didn't and just want to see it again), NASA's posted the video of the launch.

The Soyuz will reach the International Space Station and dock on Wednesday at 12:38 am EDT.

"The Soyuz rocket is seen in the monitor of a video camera moments before Soyuz Commander Gennady Padalka and flight engineers Joseph Acaba and Sergei Revin arrived to board the rocket at the Baikonur Cosmodrome in Kazakhstan for their flight to join their crew mates already aboard the International Space Station. The craft successfully launched at 11:01 p.m. EDT, Monday, May 14, 2012.

The trio will dock to the station’s Poisk Mini-Research Module at 12:38 a.m. Thursday, bringing Expedition 31 to its full six-member complement."

"Best known as a swan winging its way across the night, the constellation Cygnus is easily seen in the northern hemisphere's summertime sky. This new view of the Cygnus-X star-forming region by the Herschel Telescope highlights chaotic networks of dust and gas that point to sites of massive star formation. This image combines far-infrared data acquired at 70 micron (corresponding to the blue channel); 160 micron (corresponding to the green channel); and 250 micron (corresponding to the red channel). The observations were made on May 24, 2010, and Dec. 18, 2010.

Herschel is a European Space Agency cornerstone mission, with science instruments provided by consortia of European institutes and with important participation by NASA."

From the volatile landscape of Io, pockmarked by eons of volcanic activity, to Ganymede’s saltwater oceans sandwiched between hundreds of miles of ice and rock, Jupiter’s so-called Galilean moons are uniquely diverse and act like a miniature solar system.

“Jupiter is an archetype of gas giants,” says Werner Magnes from the Space Research Institute at the Austrian Academy of Sciences in Graz, Austria. “It’s a kind of mini-solar system, which means Jupiter acts like a star in a minisystem with its moons acting like planets.”

That’s why the European Space Agency chose the distant gas giant’s icy moons as the target of its next big scientific mission. The 19-member group opted this month to send a spacecraft to explore and investigate the satellites, which are located some 500 million miles away from Earth. The plan is to launch the Jupiter Icy Moons Explorer, or JUICE, in 2022.

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Nestled in the deep trenches of the Guatemalan rain forest, at the largest-known Classic Mayan site, Xultún, scientists have uncovered the remnants of what appears to be the earliest known Mayan calendar and murals.

Contrary to popular myth, Mayan experts have known for a long time that this calendar is not a countdown to the end of the world on December 2012, the study researchers said in a press conference to reporters.

The Mayan used a series of cycles to track time in which there were 13 baktuns each representing a 400-year chunk.

Researchers of the study say rumors surrounding a projected apocalypse on December 21, 2012, is a misconception. It is just the benchmark when a cycle of 13 baktuns will be complete and a new cycle begins.

“There was a lot more to the Mayan calendar than just 13 baktuns," said archaeologist David Stuart of the University of Texas, who worked to decipher the hieroglyphics found on the walls of a house, dating back to the early part of the 9^th century (813 A.D.-814 A.D.).

"The Mayan calendar is going to keep going for billions, trillions, octillions of years into the future," added Stuart.

Archeologists working in the region stumbled upon these ruins back in 2010, while exploring the site of Xultún. They say the artifacts were well preserved in a never before seen house-like structure, which appears to be a workspace for Mayan scribes.

“It was actually my student, Max Chamberlain, who discovered to the Mayan house, while poking around a looters’ trench,” said William Saturno, lead author and archeologist at Boston University.

Due to the fluctuations in the wet and dry climates of the tropical regions in the rain forest, scientists did not expect these artworks to preserve well.  At first glance, Saturno and his research team did not think their findings would amount to anything.

“Initially, when we went to verify this as a Mayan painting, all we could see at the time was a single red line on a really moldy, dilapidated piece of stucco that had been uncovered by looters about 30 years earlier," said Saturno.

“In order to gain a better understanding of the dimensions of the house, I began excavating the looters’ trench to the back wall, I was shocked to find a beautifully preserved image of a Mayan king on his throne, with a great blue feathered head dress streaming off his head,” added Saturno.

Preserved paintings were found on the ceiling and on three of the four walls, covering the west and north walls of a small 6.6-foot-by-6 foot room, with a vaulted roof.  On the east wall, someone had painted a series of small, complex hieroglyphics.  The newly discovered calendar, features bars and dots recording lunar cycles in six-month chunks of time. The markings tipped the researchers off,  suggesting that on top of the wall murals was actually a calendar.

“All around us were paintings, we saw many life-size human figures painted in black and red hieroglyphs,” said Saturno.

Despite the remarkable findings, this team of researchers say they have only scratched the surface.

“We have 99.9 % of Xultún left to explore,” said David Stuart.

“Its actual boundaries have yet to determined and we are going to be working on it for many decades to come,” said Stuart.

The findings, supported by the National Geographic Society, are set to be published in a forthcoming article in the journal Science on Friday.

Vesta, the second-largest object in our solar system's asteroid belt, is a protoplanet, according to research released Thursday. Scientists reviewed data from the Dawn spacecraft orbiting Vesta and concluded that Vesta is protoplanet that survived numerous collisions with other space rocks since it formed more than 4.5 billion years ago.

"Dawn’s mission at Vesta has been a spectacular success. It’s transformed Vesta from a fuzzy orb into a planetary body," said Carol Raymond, the deputy principal investigator for Dawn at NASA's Jet Propulsion Laboratory in Pasadena, California.

Becoming a protoplanet is an upgrade from Vesta’s previous designation as an asteroid or minor planet. It means Vesta’s structure shows it has a dense, layered body and orbits the sun, like the Earth and other rocky planets. Vesta didn’t quite make it to full-fledged planet, but Raymond said it's more like a planet than an asteroid.

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For decades, research into the heliosphere – the bubble of solar-wind-blown particles that surrounds our solar system – has assumed that the heliosphere's motion produces bow shock, a shock wave of ionized gas or plasma preceding the bubble as it moves through space.

New information from NASA's Interstellar Boundary Explorer (IBEX) reveals that this phenomenon doesn't actually occur.

You might be familiar with bow shock in terms of the sonic booms caused by planes flying faster than the speed of sound. David McComas, lead investigator for the IBEX mission team that completed this new analysis, explains, "As the jet reaches supersonic speeds, the air ahead of it can’t get out of the way fast enough. Once the aircraft hits the speed of sound, the interaction changes instantaneously, resulting in a shock wave."

Though telescopes have observed bow shock preceding other stars, IBEX has shown that our heliosphere doesn't move fast enough in the galactic gas and dust to produce the same effect. In an article in the online journal Science, the IBEX team reports that the heliosphere moves about 7,000 miles per hour slower than previously thought.

Does this mean the sun itself is moving slower? Compared to the interstellar medium, yes, but compared to the other stars around it, not so much.

Moreover, IBEX and the Voyager spacecraft have both shown that the magnetic field in the interstellar medium is strong enough to require the heliosphere to move even faster in order to produce bow shock.

The new data means that years' worth of research needs to be re-examined, McComas said in a statement. "Already, we know there are likely implications for how galactic cosmic rays propagate around and enter the solar system, which is relevant for human space travel."

Humans traveling outside of the relatively safety of Earth's magnetic field, which deflects some radiation, would be exposed to cosmic rays and risk effects like cancer.

"A brightly reflective Enceladus appears before Saturn's rings, while the planet's larger moon Titan looms in the distance.

Jets of water ice and vapor emanating from the south pole of Enceladus, which hint at subsurface sea rich in organics, and liquid hydrocarbons ponding on the surface on the surface of Titan make these two of the most fascinating moons in the Saturnian system.

Enceladus (313 miles, or 504 kilometers across) is in the center of the image. Titan (3,200 miles, or 5,150 kilometers across) glows faintly in the background beyond the rings. This view looks toward the anti-Saturn side of Enceladus and the Saturn-facing side of Titan. The northern, sunlit side of the rings is seen from just above the ringplane.

The image was taken in visible green light with the Cassini spacecraft narrow-angle camera on March 12, 2012. The view was acquired at a distance of approximately 600,000 miles (1 million kilometers) from Enceladus and at a Sun-Enceladus-spacecraft, or phase, angle of 36 degrees. Image scale is 4 miles (6 kilometers) per pixel on Enceladus."