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Citizen science: Time asteroid occultation from Houston area 12/24

Help us observe and time an eclipse of a 8.2 magnitude star as it is occulted by 13th magnitude, 23 mile wide asteroid Fama as the shadow path crosses over Texas! It is not necessary to spot the asteroid. Just watch what it does to the star. Check out the map above. If you are located from central to east to west Texas your house may be in the path between the two RED parallel lines. On the early morning of Wednesday Dec. 24 you can stay at home, take out your scope and time this event. Print out the 5 levels of star charts by going to this URL:

http://www.asteroidoccultation.com/2014_12/1224_408_33417.htm

From Houston-Beaumont area the star will wink out at 3.06.04am Central Time for up to 3.3 seconds; from the Austin- San Antonio area (including Kerrville, Fredricksburg and Marble Falls) the same thing happens at 3.06.30. From Ft. Davis the occultation occurs at 3:07:17am. There is no Moon in the sky and the elevation of the star is over 70 degrees, above azimuth 253 in East TX. RA and Dec of the star is:

RA: 07 42 00.2406 DE: +24 03 01.331. It is located near Kappa Geminorum.

If you have the ability to locate stars without help, you can do this just with a telescope (preferably motor driven) and a smart phone! Two new apps make this possible.

TIMING APPS: For Android phones, the app is called “TimeTheSat”; for iPhones, the app is “Emerald Timestamp”. You need to have an internet connection outside when running the apps!!

TimeTheSat: https://play.google.com/store/apps/details?id=com.satflare.timesat&hl=en

Emerald Timestamp: http://www.emeraldsequoia.com/ts/index.html

Once you have downloaded the app, it will bring up a running clock in UTC (universal coordinated time). For this to be used effectively, you need to have a wireless internet connection when observing. Hold the smart phone comfortably while looking through the telescope, such that your hands must not have to worry about touching the scope or anything else—just the smart phone. It is best to use a polar aligned telescope centered on the target star. But if you have dark skies and a wide field eyepiece, even a non-motor driven scope 6 inches in aperture or larger will work.

When the star disappears, tap the phone once and the time will be recorded; be quick as it will reduce the human error factor! Then within a second or two the star will pop back and you want to tap the phone again. Remember, without the following information, your report has limited value.

Please report negative or positive observations to pdmaley@yahoo.com and provide ALL of the info below:

  1. name
  2. email/phone
  3. times of disappearance and reappearance
  4. coordinates of your site using this interactive map:

    http://www.poyntsource.com/New/Google/20141224_33417.HTM

    Simply zoom in on your location and place it in the center of the map; then copy and paste the line of information that appears below the map. For example:

    (Map center is at (WGS84 datum) Lat = 30.141415982780384, Lon = -98.2418704032898, which is 0.436 Km from path center.)

  5. information on your telescope
  6. app used (or other method)
Paul D. Maley NASA JSC Astronomical Society and International Occultation Timing Association