Penny For Your Martian Thoughts: This Is How A Coin Looks After 14 Months On The Red Planet

A high-power camera on the Mars Curiosity rover snapped a picture of a 1909 American penny featuring Abraham Lincoln. The coin is used as a calibration target for the Mars Hand Lens Imager  (MAHLI) that is at the end of Curiosity’s robotic arm. In just over an Earth year on the Red Planet, you can see the bright copper is muted by lots of Mars dust.

Although the image has public relations appeal, there are scientific reasons behind picking that particular calibration target. It is supposed to measure how well the camera is performing, which is important as it zooms in on interesting features on Mars.

“The image shows that, during the penny’s 14 months (so far) on Mars, it has accumulated Martian dust and clumps of dust, despite its vertical mounting position,” the Planetary Science Institute stated.

Curiosity’s calibration target, shown before launch. Two instruments at the end of the robotic arm on NASA's Mars rover Curiosity use the calibration targets attached to a shoulder joint of the arm. Credit: NASA/JPL-Caltech
Curiosity’s calibration target, shown before launch. Two instruments at the end of the robotic arm on NASA’s Mars rover Curiosity use the calibration targets attached to a shoulder joint of the arm. Credit: NASA/JPL-Caltech

“At 14 micrometers per pixel, this is the highest resolution image that the MAHLI can acquire,” the statement added.

“This image was obtained as part of a test; it was the first time that the rover’s robotic arm placed the MAHLI close enough to a target to obtain MAHLI’s highest-possible resolution. The previous highest-resolution MAHLI images, which were pictures of Martian rocks, were at 16-17 micrometers per pixel. A micrometer, also known as a micron, is about 0.000039 inches.”

Check out more about the history of this penny in Ken Kremer’s past article for Universe Today. Curiosity has a two-year prime mission on the Red Planet. Since landing in August 2012, it has already uncovered evidence of past water and gone on a search (in vain) for Mars methane.

Source: Planetary Science Institute

Curiosity’s Sundial Carries a Message of Hope

 A recent high-definition image from Curiosity’s Mastcam shows the rover’s sundial (NASA/JPL-Caltech)

While Curiosity is definitely loaded up with some of the most high-tech instruments ever made to investigate the surface of Mars, it also carries a very low-tech instrument: a sundial (aka the “MarsDial”) which can be used to determine the position of the Sun in the sky and the season on Mars just like they do here on Earth. Curiosity’s sundial also has additional color calibration tools for the rover’s Mastcam, which captured the image above on August 19 — the 13th “Sol” of the mission.

The connection between a device invented by people thousands of years ago being in use today on a robotic explorer on another planet didn’t go unnoticed by the Mars Exploration Rover team either; in addition to the words “Mars 2012” and “To Mars, To Explore” around its top bezel, Curiosity’s sundial also carries a message of history, hope and inspiration printed along its edges…

Along with line drawings and the word for “Mars” in sixteen languages, Curiosity’s sundial bears the following inscription:

“For millennia, Mars has stimulated our imaginations. First, we saw Mars as a wandering star, a bringer of war from the abode of the gods. In recent centuries, the planet’s changing appearance in telescopes caused us to think that Mars had a climate like the Earth’s. Our first space age views revealed only a cratered, Moon-like world, but later missions showed that Mars once had abundant liquid water. Through it all, we have wondered: Has there been life on Mars? To those taking the next steps to find out, we wish a safe journey and the joy of discovery.”

Curiosity’s successful landing on Mars at 10:31 p.m. on August 5, 2012 (PDT) was only the first (although very exciting!) step of its mission, and the first of hopefully many next steps to explore our neighboring world. Perhaps one day this message will be revisited by human explorers on Mars who may then reflect back on how it all began, and all of the innovations, hope and — well, curiosity — that made each of their rust-dusted steps possible.

Follow the sun, Curiosity!

Find out more about Curiosity’s many science and exploration instruments on JPL’s interactive 3D page here, and keep up with the latest MSL downloaded images here.