Virgle

Virgle is an April Fool's Joke from Google, like previous ones that they have made, like Google Gulp and Google TiSP. It proposes a "Plan B," carried out over a hundred years, that will aim to colonize the red planet, Mars, by Virgin and Google teaming up. You can even fill out an application to become a "pioneer" in this endeavor, and watch video messages by Larry Page and Sergey Brin, cofounders of Google, and Richard Branson of Virgin. However, it is just an April Fool's joke. But Google points out in one of the pages on the Virgle website, "Virgle isn't real. Yet."

The information on Virgle's website are mostly all based on facts. In fact, if you read the FAQ on the website, you can learn a lot about Mars, terraformation, etc. As Google suggests on an obscure web page stating that Virgle is not real yet, all of this can become reality in the future. Terraforming, as Wikipedia explains, is the process that can make a planet or any other body in space have a similar environment to that of the Earth, to make it habitable for humans. This process is possible and may even take place in the near future. Also, Google suggested a self sustainable base on Mars. This too is also a viable possibility, that may take place as humans look to expand their horizons and settle out of Earth.

So, you can get a good laugh by going to Virgle, but keep in mind, all of this may be reality in the future.

Image from Google.com

The video messages of Larry Page, Sergey Brin, and Richard Branson are posted below:

Cassini Meets The Jets of Enceladus

NASA's Cassini spacecraft made a close flyby on Wednesday March 12 of Enceladus, one of Saturn's numerous moons. Cassini flew by the moon at 15 kilometers per second (32,000 mph), through icy water jets, that are similar to geysers. With the information from the flyby, the tiny ice moon Enceladus is revealed to be active and hot. It also has a lot of water vapor and organic material.

There are many fractures running along the moon's south pole, from which the geysers shoot out water vapor at 400 meters per second (800 mph). The geysers added evidence that there may be liquid water under the icy crust of Enceladus.

Also, new heat maps of Enceladus taken by Cassini show higher temperatures in the south pole region, and hot tracks running along the fractures (see image at right). The strips of warmth, also called "tiger stripes," are giant fissures that are the source of the geysers.

The surprising thing about all this news was that the material coming from the inside of Enceladus resembles that of a comet. The Ion and Neutral Mass Spectrometer aboard the Cassini spacecraft saw a combination of volatile gases, water vapor, carbon dioxide, carbon monoxide, and organic materials. It seems that all of these materials are pointing ton one thing: life. However, the final ingredient, liquid water, has not been confirmed yet.

All of these developments may lead to more information about the formation and composition of Saturn and its moons.

For more information:

• An animation of the jets on Enceladus (requires Quicktime).
• NASA Mission News (1, 2).
• Wikipedia (Cassini, Enceladus).

Avalanche!

The High Resolution Imaging Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter has captured images of enormous clouds of dust and ice rolling down a steep slope (Click on the images at left for a larger view). The pictures were taken on February 19, and have just been recently released by NASA.

The images contain a steep slope more than 700m (2,300 ft.) tall. The location of these pictures had been repeatedly focused upon to check upon seasonal changes, specifically springtime changes in the carbon-dioxide frost covering on a dune. However, these set of images revealed these avalanches. "It really surprised me," said Ingrid Daubar Spitale of the University of Arizona at Tucson. "It's great to see something so dynamic on Mars. A lot of what we see there hasn't changed for millions of years." She was the first person to notice these avalanches on Mars.

NASA does not yet know what has caused these landslides on Mars. They say they will continue to monitor this region to see if these avalanches take place year round, or only in the springtime. A reddish layer rich in liquid water forms the majority of the slope. It is predicted that more ice fell than dust, leading to researchers studying the base of the slope to check its composition showing what part is ice. Researchers also predict that the blocks of ice falling in the avalanche probably turned from solid to gas, and will see if blocks of ice and other debris get smaller suggesting the theory. NASA hopes that the information gained from this will help us understand more about the Martian water cycle.

For more information, visit:

• NASA Mission News
• Wikipedia: HiRISE

Leap Year

If you haven't looked at the calendar today, it's February 29, 2008. February 29 only occurs on leap years, and 2008 happens to be one. So what exactly is a leap year?

Basically, a leap year is a year containing one extra day. It supposedly is every year evenly divisible by 4, but it's more complex than that.

A tropical year, or solar year, is approxima

tely 6 hours more than 365 days. 6 hours is a quarter of a day, so one year is approximately 365.25 days long. Therefore adding one more day to the calendar every 4 years would make sense, making an average year 365.25 days long, and that's exactly what the Julian calendar does. But notice that a solar year is only approximately 6 hours more than 365 days; it's actually a bit shorter, about 365.24237

4 days long, and increasing. So to better approximate the length of the year, a better system was developed.

The Gregorian calendar is the most widely used one in the world. It was decreed by Pope Gregory XIII in 1582 to make sure Easter and the Vernal Equinox would fall at the same time. It modified the Julian calendar with a new rule. Leap years are years exactly divisible by 4, except years that are exactly divisible by 100, but centurial years exactly divisible by 400 are still leap years. What that means is that the 

year 1900 was not a leap year, but 2000 was. While in the Julian calendar, both 1900 and 2000 were leap years. The Gregorian calendar results in a better average year: 365.2425 days long, which gives a more accurate approximation.

Update: Google has made a Google Doodle for the Leap Year. It shows a frog "leaping" instead of the l in Google.

Calling All Amateur Astronomers!

April 12, 2008 is the 2nd International Sidewalk Astronomy Night. Sidewalk astronomy, started by John Dobson, designer of the Dobsonian Telescope Design, is a kind of astronomy that showcases some items of the night or day sky, like the Moon, Saturn, and Jupiter, to the public. Sidewalk astronomers set up their telescopes in urban areas for people passing by to look and admire the night sky, free of charge.

International Sidewalk Astronomy Night hopes to get many participants all across the globe so they can reach more people and unite astronomers worldwide. If you have a telescope, have access to an area with lots of people where you can set up your telescope, and are willing to spread the wonders of Astronomy and Space, then sign up!

For more information:

• 2nd International Sidewalk Astronomy Night
• Wikipedia: Sidewalk Astronomy

Clouds on Mars?!

How can clouds exist on a planet that has a thin atmosphere and little moisture? Isn't Mars just a desert planet?

Most of the time, Mars is cloudless, but temperatures often plummet below the freezing point of carbon dioxide. Carbon dioxide, which is the most abundant gas in the Martian atmosphere, freezes into thick clouds due to the low temperature. The frozen carbon dioxide, called dry ice on Earth, can block the sun by 40 percent. The direct observations conducted by the European Space Agency's Mars Express have confirmed the clouds, whose existence has been previously suggested.

The clouds' density and makeup is very surprising. They are made up of CO₂ particles larger than a micron(a micron is one thousandth of a millimeter) across.The particles normally would not be expected to form in the upper atmosphere, or stay in the air before returning to the surface. The clouds are also very high, reaching heights of more than 80 km (or about 50 miles) above the surface of Mars. The Martian clouds can also span hundreds of kilometers.

The French scientists who made the discovery know that the carbon dioxide clouds are most common near the equator of Mars, most probably because of the temperature variations there. Small amounts of warm gas rise above the planet, cooling off and condensing as they reach higher altitudes. When they release latent heat (the energy absorbed or released during a change of state), they rise even further. What these scientists haven't confirmed yet is what they condense around. Cloud droplets condense around sand or dust on our planet, but on Mars, there are many different possibilities. Martian dust kicked up by winds, or micrometeorites entering the atmosphere, or maybe even tiny crystals of water ice.

The importance of the discovery is that scientists can now learn more about the past climate of Mars. The planet is theorized to have been warmer billions of years ago, with CO₂ clouds more covering up the atmosphere. The clouds could have played a big role in the global warming of Mars.

For more information, read the article on the ESA Mars Express website detailing the discovery. You can also read about Mars Express and the Climate of Mars on Wikipedia.