Slashdot Mirror
Mars Lander Snaps the Most Detailed Pics Yet
An anonymous reader writes "The Mars Lander has taken its very first microscopic image of a piece of Martian dust (image). The particle, according to the Jet Propulsion Laboratory, is shown at a higher magnification than anything ever seen from another planet. The piece of dust is a rounded particle about a millionth of a meter across. This particle is one of the countless specks of dust that continually swirl around the Red Planet, coloring the Martian sky pink. 'Taking the images required the highest resolution microscope operated off of Earth and a specially designed substrate to hold the Martian dust,' said Tom Pike, a Phoenix science team member. 'We always knew it was going to be technically very challenging to image particles this small.'"
The original source for this story is here. Updates and raw daily images directly from the team running the mission are here.
Saddle up: Riding with Robots
I don't know why so often we get articles linked to sources completely unrelated to the topic at hand. I understand and appreciate PCMag having articles unrelated to PC's occassionally for the edification of their readers, but there's no reason not to get a topical source for sharing on Slashdot. Space.com and spaceref.com are great news sites for lay-persons, and one thing NASA is generally outstanding about is having detailed, up-to-date, and accurate mission websites.
/rant
Anyways, I think calling this a picture affects readers' expectations. The atomic force microscope is a coordinate mapping tool rather than a camera. It uses tiny probes to sense the surface profile of a target and create elevation maps based on that data. It's more of a three-dimensional graph than a picture and it doesn't use light, but it can reveal much finer details than an optical microscope can.
Here's a similar image to that linked in the summary overlayed with an optical microscope picture of the same area. Note that the optical microscope image is about 3 mm across, of a target of micromachined silicon that has a bunch of tiny pits, posts, and bumps intended to hold dust particles of different types. The atomic force microscope image is 100 times the resolution of the optical image.
Actually, even the optical microscope on Phoenix is far higher resolution than any camera previously flown to another world, but the AFM takes the capability two steps further. Between the two, the Phoenix team is learning a lot about the soil on Mars that should allow them to deduce not only its bulk properties, but even hints about how it formed.
By the way, the Mars Rovers have "microscopic imagers," but these are really more like close-focus cameras than true microscopes. Offhand I can't think of any other robotic space missions that carried microscopes.
Spirit and Opportunity each have a microscopic imager, so that's two. Any more?
If you want to get technical, the correct way to spell the standard SI unit of length is "metre", not "meter", in most countries except the U.S. This leads to the convenient distinction that a "meter" is a device used for measurement (such as the micrometer you mention), whereas a "metre" is a unit of measurement. Therefore, a micrometre is what you are looking for, usually abbreviated with the Greek letter mu, which I can't seem to get to display properly here, followed by an m. It is also commonly called a "micron", although that usage is informal.