Sci-Tech Briefs

Dawn launched into space

On Thursday,NASA launched the Dawn spacecraft to explore the asteroid Vesta and the dwarf planet Ceres. Dawn will give scientists a better idea of how the solar system came into existence.

Most of Dawn’s speed builds slowly over time, so Dawn will take four years to reach Vesta. Three hundred miles in diameter, Vesta has a rocky surface similar to that of Earth. On its way, Dawn will slingshot around Mars in February 2009.

After six months of observations at Vesta, Dawn will start a three-year trek to Ceres, where water may be present. Dawn is expected to compare the two worlds of Vesta and Ceres with the help of instruments on board.


Crocodiles travel back home

Using satellites, researchers have determined that crocodiles may travel up to 411 km to return home from foreign territory in a matter of weeks.

Australian scientists attached tracking equipment to three salt-water crocodiles. They then moved the crocodiles to different territories, 56 km, 99 km, and 126 km away from their homes.
After a few weeks, each crocodile set off back home, taking five to 20 days to get back. The farthest crocodile traveled a total of 411 km around the coastline.

Contrary to popular belief, the fact that crocodiles can swim for long periods of time suggests that they have an aerobic (use of oxygen) metabolism. The experiment also shows that crocodiles may be using Earth’s magnetic field, substances in the water, and the sun’s position to get back home.


Printer produces 3-D objects

U.S. researchers are on their way to putting 3-D printers on the market. This printer is capable of printing actual objects, such as staplers or envelopes.

The ability to print model objects is called ‘rapid prototyping.’ The printer works with the help of lasers. The system first reads a 3-D image of the object and then uses lasers to form the object out of plastic.

In the future, rapid prototyping may be used by product developers to exchange prototypes of certain objects.


Birds use sight to detect magnetic fields

German researchers have revealed that migrating birds used Earth’s magnetic field as a guide for travel. Researchers suspect that birds see magnetic fields as shadows or spots of light.

Scientists have known that birds use magnetic fields to guide their travel, but up until now, they have not known how. The current study shows that birds depend on vision for detecting magnetic fields.

According to researchers on this project, birds have cryptochromes in their eyes, which are molecules that detect magnetic fields. These molecules stimulate other cells in the eye that detect light, resulting in a visual appearance of the magnetic field.

Source: Reuters