PROVIDENCE, R.I -- Fall in the Northern Hemisphere begins Sunday at 4:44 p.m., the autumnal equinox. Of course, that's when spring begins in the Southern Hemisphere.
This is the time when the sun crosses the equator and moves south, when the days and nights are approximately equal in length, but the days will soon grow shorter.
Ladd Observatory to launch display
Michael Umbricht, curator of Brown University's Ladd Observatory, reports that the observatory has obtained a space shuttle general computer from NASA's Johnson Space Center.
"Another historic item that we also now have is a hand-held programmable calculator that was used by astronauts in the space shuttle," he said via email.
He said the items will be the centerpiece of a display about navigation in the space age. It will include items related to Prof. Charles Smiley, former director of the observatory. During the late 1950s, Umbricht said, Smiley measured the position of the Sputnik 1 and Sputnik 2 satellites in the sky and used those observations to compute the orbit.
"During this era computers were relatively rare, and our display will include a mechanical adding machine that he used for orbital calculations. The display will be ready in time for the Oct. 4 anniversary of the launch of Sputnik 1," Umbricht said.
No methane on Mars
In news from NASA, data from the Mars Curiosity rover has revealed the Martian environment lacks methane, a surprise to researchers because previous data reported by U.S. and international scientists indicated positive detections, the space agency said.
Methane could be a potential sign of life, although it also can be produced without biology.
"This important result will help direct our efforts to examine the possibility of life on Mars," Michael Meyer, NASA's lead scientist for Mars exploration, said in a news release. "It reduces the probability of current methane-producing Martian microbes, but this addresses only one type of microbial metabolism. As we know, there are many types of terrestrial microbes that don't generate methane."
The car-sized Curiosity landed inside Gale Crater on Mars in August 2012 and is investigating evidence about habitable environments there.
For more information about the mission, visit:
So that's what that was
For those who missed it, asteroid 2013 RZ53 passed between Earth and Moon Wednesday. The three-meter rock was discovered Sept. 13. It missed Earth by just more than half the distance to the Moon's orbit.
Local observatories:
Seagrave Memorial Observatory in North Scituate is open every clear Saturday night.
Ladd Observatory in Providence is open every clear Tuesday night.
Frosty Drew Observatory in Charlestown's Ninigret Park is open every clear Friday night.