Archive
11/15/2013 – Ephemeris – New information on the Chelyabinsk meteor
Ephemeris for Friday, November 15th. The sun will rise at 7:39. It’ll be up for 9 hours and 34 minutes, setting at 5:14. The moon, 2 days before full, will set at 6:34 tomorrow morning.
Articles in Nature and Science bring some precision to the Chelyabinsk meteor of February 15th. Its orbit is very close to a known but unnamed asteroid 86039 discovered in 1999, and may be a piece broken off from it. The meteorite retrieved from the nearby lake broke when it was attempted to be weighed. It turns out that a security camera recorded the splash as the large piece hit the lake and broke through the ice. The fragility of the meteorite testifies as to why it exploded in the atmosphere. The meteor was recorded from satellites, infra-sound recorders from the International Test Ban Treaty Organization, and a host of dashboard cams. The blast, depending on who did the measuring could have been up to 600 kilotons. (The bomb that was dropped on Hiroshima had a yield of 16 kilotons).
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Caption: Witness photo of 2013 Russian meteor event made from Chelyabinsk Drama Theater. Photo by Nikita Plekhanov.
11/14/2013 – Comet ISON has an outburst
Last night Comet ISON suddenly brightened and may be bright enough to be visible to the naked eye.. The comet is now within the orbit of Venus and falling with increasing velocity toward the sun for its November 28th perihelion.
Here’s a link to Universe Today‘s post with lots of photos.
EarthSky also has an entry for it: with a finder chart for naked eye viewing of the comet in twilight.
Here’s SpaceWeather.com‘s entry for today.
This may bode well for the comet’s brightness after perihelion, if the comet’s nucleus holds together or stays in big enough pieces. The next week may tell.
Bob Moler's Ephemeris Blog 