Thursday, July 2, 2015

Pax Occults Star at GSSP

Blotting out the Stellar View

As seen on the Golden State Star Party facebook page, the asteroid Pax will pass through the path of light from a star, causing a drop of 3 magnitudes.

Should be an interesting event to see and possibly record.

All content from the Asteroid Occultation page, I'm linking it here to make it easier to remember.



Detailed Summary:

Summary
-------
On 2015 Jul 17 UT, the 61 km diameter asteroid (679) Pax will occult a 8.3 mag
star in the constellation Sagittarius for observers along a path across W
Canada, W USA.

In the case of an occultation, the combined light of the asteroid and the star
will drop by 3.7 mag to 12.0 mag (the magnitude of the asteroid) for at most 4.3
seconds.

This update is based on UNSO/Flagstaff astrometry for the asteroid kindly
provided by Alice Monet, historical astrometry from the MPC files (via AstDys),
and the following catalogs for the star position: .

The event at a glimpse
----------------------
    * Rank: 95
    * date and approx. time of event: 2015 Jul 17, 05:48  - 2015 Jul 17, 05:55  UT
    * geocentric midpoint of event [JD]: 2457220.74455
    * magnitude of target star: 8.3
    * magnitude drop [mag]: 3.7
    * estimated maximum duration [s]: 4.3
    * Moon: 2 % sunlit, 155° distance
    * Sun: 168° distance
    * rough path description: W Canada, W USA

The occultation path
--------------------
    * approximate projected width [km]: 112
    * 1 sigma uncertainty interval [path widths]: +/- 0.44
    * 1 sigma uncertainty interval [seconds]: +/- 1.7
    * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .030 +/- .021)
    * 1 sigma uncertainty ellipse (major, minor, PA): ( .031", .020", 103° )
    * approx speed of asteroid's shadow [km/s]: 14.1926
    * website for maps:
          http://www.asteroidoccultation.com

Maps:

Star Charts:
15 Degree View
Wide Field

5 Degree View

2 Degree View
30 Minute View