Hi-ho, hi-ho, it’s off to Glenelg we go! Scientists with the Mars mission have chosen Curiosity’s first exploration destination, a little place nicknamed Glenelg (after a village in Scotland) near the base of an alluvial fan of sedimentary rocks, dirt and sand. Alluvial fans are common on Earth as streams flowing from mountains or canyons gradually spread out and deposit rocks and sand in great fans onto the flatter plains below.
Curiosity landed near the base of a similar fan-deposit on Mars; scientists will drive the rover further downhill to where the water might have collected. They’ll be looking for things like salts that are dissolved by water but later precipitate as solids when the water evaporates.
Glenelg. Notice anything peculiar about it? It’s a palindrome, a word or phrase that reads the same way in either direction. Fun examples include “kayak”, “evil olive”, “tangy gnat”, “radar” and “Oh, cameras are macho”. NASA folks selected Glenelg because the rover will be visiting the area twice – both coming and going – before it turns around and heads to the base of Mt. Sharp. Having a sense of humor makes any job more fun.
The rover will travel 1,300 feet (400 meters) to the east-southeast of its landing spot to reach Glenelg; its first drilling target will be a section of layered bedrock (likely sedimentary rock deposited by or in water). Prior to departure, the team in charge of ChemCam will zap a 3-inch rock 10 feet away named N165 with a powerful laser. The resulting spark of vaporized rock will be examined with a spectroscope to determine the minerals that make up the rock. The rover will also exercise its wheels in the coming days before moving out.
If one of your destinations is tonight’s sky, you’ll again be able to watch the International Space Station (ISS) fly by. I saw it unexpectedly last night making a brilliant pass across the northern sky. Most of the station’s passes continue to be in the north for the next few nights.
I’d also like to point out that we’re now entering the best time of year for northern hemisphere sky watchers to enjoy the sight of the bright summertime Milky Way. This hazy band of light made of a multitude of stars crosses overhead from the W of Cassiopeia in the northeast all the way to the southern horizon. While the moon is still “missing” from the evening sky, take a drive out to the countryside to relish a view of the galaxy we call home.
Space station viewing time for Duluth, Minn. and region:
* Tonight Aug. 18 starting at 9:36 p.m. across the northern sky
* Sunday Aug. 19 at 8:45 p.m. in the north and again at 10:21 p.m. During the second pass the ISS rises in the northwest and dramatically fades as it enters Earth’s shadow near the bright star Vega.
* Monday Aug. 20 at 9:30 p.m. Near-overhead pass
* Tuesday Aug. 21 at 8:38 p.m. in early twilight and again at 10:14 p.m.
for a brief pass in western sky