Archive
10/04/11 – Ephemeris – Good news on the NEO front
Tuesday, October 4th. The sun will rise at 7:43. It’ll be up for 11 hours and 34 minutes, setting at 7:18. The moon, 1 day past first quarter, will set at 1:16 tomorrow morning.
In the last couple of years the WISE satellite, an infrared survey satellite, has been primarily mapping targets for the James Webb Space Telescope proposed to be launched later this decade. As a bonus was the discovery of a great number of asteroids including Near Earth Objects or NEOs. The survey concluded that there are most likely fewer threatening asteroids of all sizes that had been estimated before. That’s definitely good news. However the numbers of asteroids less than 300 meters in diameter is still pretty much unknown. That’s the size of the Apothis asteroid that will pass under the geostationary satellite orbits in 2029. Asteroids that size are still killers, such as the rock that made the crater in Arizona, and another the Tunguska event in Siberia.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
10/03/11 – Ephemeris – More celestial events for this month
Monday, October 3rd. The sun will rise at 7:42. It’ll be up for 11 hours and 37 minutes, setting at 7:19. The moon, at first quarter today, will set at 12:10 tomorrow morning.
We have more celestial happenings this month than I could enumerate last Friday. Later on Saturday evening, if it’s clear the Grand Traverse Astronomical Society will join with astronomy groups, planetariums and observatories with International Observe the Moon Night with telescopes positioned on the 200 block east Front Street in Traverse City, near the Martinek clock. Going on that same evening will be the return of the Draconid meteor shower. Its a favorable return of a periodic shower but interferes with by the bright moon. However some bright meteors will be seen. I’ll have more information and background Thursday. Another meteor shower later this month will be the Orionids a morning shower related to Halley’s Comet.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Bob Moler's Ephemeris Blog 