Wednesday, April 27, 2005

Whirlwinds Carrying Dust on Mars

This is an encrypt of an article i cut from Nasa Mars Rover Misson Web Site. I want to show it to this blog because it is an interesting thing to know that we as human living in earth have a robots doing research at planet Mars far away from earth. I see this robots as a small steps for mankind of going to explore to outer space one day and i hope that i can see it before my time ended.

This movie clip shows a dust devil scooting across a plain inside Gusev Crater on Mars as seen from the NASA rover Spirit's hillside vantage point during the rover's 459th martian day, or sol (April 18, 2005). The individual images were taken about 20 seconds apart by Spirit's navigation camera, and the contrast has been enhanced for anything in the images that changes from frame to frame, that is, for the dust devil.

The movie results from a new way of watching for dust devils, which are whirlwinds that hoist dust from the surface into the air. Spirit began seeing dust devils in isolated images in March 2005. At first, the rover team relied on luck. It might catch a dust devil in an image or it might miss by a few minutes. Using the new detection strategy, the rover takes a series of 21 images. Spirit sends a few of them to Earth, as well as little thumbnail images of all of them. Team members use the 3 big images and all the small images to decide whether the additional big images have dust devils. For this movie, they specifically told Spirit to send back frames that they knew had dust devils.

The images were processed in three steps. All images were calibrated to remove known camera artifacts. The images were then processed to remove stationary objects. The result is a gray scene showing only features that change with time. The final step combined the original image with the image that shows only moving features, showing the martian scene and the enhanced dust devils.

Scientists expected dust devils since before Spirit landed. The landing area inside Gusev Crater is filled with dark streaks left behind when dust devils pick dust up from an area. It is also filled with bright "hollows", which are dust-filled miniature craters. Dust covers most of the terrain. Winds flow into and out of Gusev crater every day. The Sun heats the surface so that the surface is warm to the touch even though the atmosphere at 2 meters (6 feet) above the surface would be chilly. That temperature contrast causes convection. Mixing the dust, winds, and convection should trigger dust devils.

Scientists will use the images to study several things. Tracking the dust devils tells which way the wind blows at different times of day. Statistics on the size of typical dust devils will help with estimates of how much dust they pump into the atmosphere every day. By watching individual dust devils change as they go over more-dusty and less-dusty terrain, researchers can learn about the turbulent motion near the surface. Ultimately, that motion of wind and dust near the surface relates these small dust devils with Mars' large dust storms.

Credit: NASA/JPL

Its is an amaizing thing to know that there are two Mars Rovers driving on the surface of mars and doing a lots of photographing and soil experimenting to find out the content of its soil, then send it back using a small antena that only can detected by deep space radio antena. How it could be happenning? Well all because of the great works of Nasa Engineer that work so hard to make it happen. Although i'm a Malaysian and not the American, i still feel proud and positive because this is not the achivement only for American itself but for all people and us humankind.

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I discovered that some one is using my name to write a comment at another people's blog. I don't know what is the intention to do it but i believe it is not a good one.

Please be notice:

1. I never write comment into chat box. I only gave comment at post comment.
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3. Police report will be made and investigation will be done to find the culprit. The owner site will be able to track the IP address of the culprits.
4. I will personally take court action against any person who ever trying to spread false impression about me or my business.