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Clickworkers
Dawn Community
Dawn
Kids
Dawn
Classrooms
Supporting Resources:
Podcasts
+ Cratering Lecture
+ Clickworks Tutorial (QT 3.1 MB)
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Welcome to Dawn Clickworkers!
Contribute to the scientific understanding of the surfaces
of solar system bodies.
Surface features help astronomers learn more about
solar system bodies. Developing the critical eye needed to
identify and measure surface features in images takes a considerable
amount of practice. Clickworkers offers you the opporunity
to fine-tune your skills. The Clickworkers
program presents a series of images from which you can identify
and measure the diameter of craters on two solar system bodies
(Mars, Eros).
In preparation for critically examining the images of Vesta
and Ceres that will be received from the Dawn spacecraft,
you can count and measure craters using data obtained
from the Near Earth Asteroid Rendezvous NEAR
spacecraft of asteroid Eros and Mars surface images from Mars
Global Surveyor.
+
Clickworkers Tutorial (Works with Internet Explorer 5.0
+, Netscape 6 +, Firefox 1.07 +)
+
Go to Clickworkers for Asteroid Eros (Works with Internet
Explorer 5.0 +, Netscape 6 +, Firefox 1.07 +)
+
Go to Clickworkers for Mars (Works with Internet Explorer
5.0 +, Netscape 6 +, Firefox 1.07 +)
+
Go to Clickworkers Home
Once you have submitted your crater counts for Eros using
the Clickworkers program, the resulting data will be analyzed
by the science community. The accumulated measurements of
many people provides an accurate measure of the number and
size of craters on a body. This information contains clues
to the age and impact history of the body's surface. Check
back for an activity that will allow you to analyze results.
Why are craters important?
- The number of craters on a surface gives information about the age of the surface—the more craters, the older the surface. This tells us about the evolution of the body, whether it is the geologic evolution of a planetary surface or the collisional evolution of an asteroid.
- Statistical studies of impact craters provide information about how the sizes and numbers of asteroids, comets, and other planetary debris have evolved over time.
- Craters excavate material from below the surface. Our instruments can detect these compositional variations on a surface and allow us to determine if the body is composed of the same materials throughout.
- Sometimes there are variations in the appearances of craters, which tell us about changes in near-surface properties. For example, ice-rich bodies sometimes show a fluidized ejecta blanket, unlike the radial pattern seen around craters on dry bodies.
- Craters help to form the geology of a body. Many ridges and fractures on asteroids and small moons are the result of craters and the impact process.
- Sometimes we see craters which are so large that the impact should have completely destroyed the body. The fact that these objects still exist with these large craters tells us that these bodies are not solid throughout their interiors. Instead these bodies are simply piles of large boulders held together by gravity. Scientists call these bodies “rubble piles”.
Nadine G. Barlow, PhD
Department of Physics and Astronomy
Northern Arizona University
Related NASA Educational Materials:
Exploring Meteorite Mysteries: The Holes in the Ground activity allows students to create impact craters in plaster of Paris or layered dry materials.
Exploring Meteorite Mysteries: In Crater Hunters students will locate impact craters on Earth using longitude and latitude and various maps.
Designing Craters: Creating a Deep Impact is a two-to-three week student inquiry into the question: "How do you make a 7-15 stories deep, football stadium-sized crater in a comet?"
Ouch That Hurts, is a student text from the Genesis Education Module: Cosmic Chemistry: Planetary Diversity.
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