Google'sVirtual Reality - 'Lively'

As if Google didn't have a strong enough hold on the planet already, today it's launching its own world -- a virtual world, to be exact. Lively, which Google likes to call a "virtual experience," allows you to create an avatar, decorate your own virtual room, invite friends to your room and do things you've always dreamed of, like blow up oil barrels on a deserted island.

Unlike popular virtual worlds such as Second Life, Lively doesn't require you to download new software. All you need is a browser plug-in. The service is also more distributed than Second Life: Its rooms will live on Web pages on Facebook and other sites, so you might stumble across them when browsing the Internet. Rooms can be private spaces, with entry by invitation only, or open-topic rooms, where you can meet people interested in discussing topics you love, like Angelina Jolie, Jennifer Aniston or Google. It also ties into other Google services. You can stream YouTube videos into your virtual living room or post your Picasa pictures on your walls.

Virtual reality is a little 2006, but Google is looking to give it a new spin with Lively, a new 3D 'world' that can be integrated with a number of online applications.

The Lively download is available now on Lively.com. Users can create "rooms" that can be embedded on blogs or Web sites and explored via avatars you create yourself.

It is currently only available for Windows XP and Vista users using Internet Explorer or Firefox. You'll need a video card with at least 32 MB of video memory, Flash 9 or higher, and a broadband Internet connection.

Users must be at least 13 years old to participate, and those under 18 must get a parent or guardian's permission before joining, Google said.

"We hope you will use the product to express yourself with and without words, and to do this in the places you already visit on the web," Niniane Wang, a Google engineering manager, wrote in a blog post. "In our user research, we've been amazed at how much more poignant it is to receive an animated hug than seeing the text '[[hug]].'"

That research included a trial with students at Arizona State University (ASU).

"Based on feedback from ASU students and with help from the Google Desktop team, we added support for playing YouTube videos in virtual TVs and showing photos in virtual picture frames inside our rooms," Wang wrote. "Better yet, the gadgets you have in your Lively rooms can also run on your desktop."

Smallest planet shrinks in size

The smallest planet in the Solar System has become even smaller, studies by the Messenger spacecraft have shown.

Data from a flyby of Mercury in January 2008 show the planet has contracted by more than one mile (1.5km) in diameter over its history.

Scientists believe the shrinkage is due to the planet's core slowly cooling.

Studies published in the journal Science show the same process also powers the planet's magnetic field, a topic long debated by scientists.

"Cooling of the planet's core not only fuelled the magnetic dynamo, it also led to contraction of the entire planet," said Principal Investigator Sean Solomon of the Carnegie Institution of Washington, US.

"And the data from the flyby indicate that the total contraction is at least one-third greater than we previously thought."

Active youth

The Messenger (Mercury Surface, Space Environment, Geochemistry and Ranging) spacecraft passed within 200km (125 miles) of Mercury earlier this year.

It was the first time the planet had been viewed up close since Mariner 10's third and final fly-by in March 1975.
A kidney-shaped volcanic vent surrounded by ejected material

The flyby was one of three to be made by the craft as it prepares to enter into orbit around the Solar System's smallest planet in 2011.

Just days after the pass, scientists revealed that they had found evidence of volcanic activity on the planet, previously hinted at by Mariner 10.

Further analysis of areas such as the Caloris basin, one of the Solar System's largest and youngest impact basins, found volcanic vents and evidence of "pyroclastic" debris blown from the volcano as it erupted.

Other areas contained circular structures with wrinkled edges, similar to structures seen on the Moon and Mars.

Scientists believe these are impact craters that have been filled with massive quantities of lava, possibly 2.7km (1.3miles) deep.

"That's a lot of lava," said Dr James Head of Brown University. "It shows the planet was really active in its early history."

Researchers believe the peak of activity could have been three to four billion years ago.

Core effects

Sensors, such as the Fast Imaging Plasma Spectrometer (FIPS), onboard the craft also revealed details of the planet's atmospheric composition.

FIPS recorded silicon, sodium and even water ions around Mercury. Ions are electrically charged atomic particles.

The scientists believe these were blasted from the surface of the planet by the solar wind, a stream of charged particles which buffets the Solar System.

Mercury's proximity to the Sun means it feels the full force of this wind, blasting atoms into space. Many of these are then trapped by the planet's magnetic field.

"The Mercury magnetosphere is full of many ionic species, both atomic and molecular," said Dr Thomas Zurbuchen of the University of Michigan.

This magnetosphere is created by the planet's core, which accounts for 60% of the planet's mass.

As well as influencing the space around the planet, the core has had an immense influence on surface features.

"The dominant tectonic landforms on Mercury, including areas imaged for the first time by Messenger, are features called lobate scarps, huge cliffs that mark the tops of crustal faults that formed during the contraction of the surrounding area," explained Dr Solomon.

"They tell us how important the cooling core has been to the evolution of the surface."