Astronomical pictures from a backyard observatory
CCD Image Index.
Cookbook 245 or Meade DSI Pro II, permanently mounted 8" f/8 newtonian telescope;

17P Holmes, the "puff ball" comet
-- Oct 28-Nov 2
-- Central Detail

Here is a way to "image" an asteroid and measure it too.
On occation an asteroid will occult (eclipse) a star.
When that happens the star will"blink" out for the time it
takes the asteroid to move through its crossection that its
path takes with respect to the observer and the star.

By timing the length and start of this event, one can determine
something about the location and size of the asteroid.

If a number of observers record the event, the size of the asteroid
can be measured to very good accuracy, and its precise location can be determined.

Most occultation observers use video recorders to measure these events.
However there is a way to do this with a ccd camera. Just prior to the
predicted event time, one turns off the telescope tracking. This provides
a streak as the star image drifts across the camera field. When the
asteroid obsures the star, the drift streak is broken, thus providing a recording of the event.

Here is my record of an event (Asteriod 153 Hilda)
that was captured by a multitude of observers last Thursday night,
[UT 07:04 July 20, 2007].





Information about asteroid occultations can be found at Steve Preston's site:
http://www.asteroidoccultation.com/
For information on asteroid occultation timing techniques, equipment and general information on the International Occultation Timing Association go to: http://lunar-occultations.com/iota/iotandx.htm

TRANSITING
EXTRA-SOLAR PLANETS

These planets are unique because their obits are inclined to the line of sight to the earth,such that the planets pass in front of their stars. Thus they are "seen" to transit the parent stars causing a significant drop in brightness of the stars.

This is the last half of TrES1-b transit on July 26, 2005. The transiting planet shows a possible anomoly at the beginning and end of the transit, a brightening just before and just after transit. This is being investigated by the professional astronomers, but was first called to attention by amateurs. In the end it may come to nothing but is worth investigating.

TRES-1 "b" is the first transiting Exo (extra-solar system) planet to be detected.
Orbital Data TrES-1_ b (taken from Alonso et al 2004)
Period: 3.030065+/- 0.00001 days
Minimum Planet Mass: 0.754Mjup
Predicted Planet Radius (with core): 1.02Rjup
Predicted Planet Radius (without core): 1.10Rjup

Planet radii from theoretical models of:
Bodenheimer, Laughlin, and Lin 2003,
Astrophysical Journal, v. 592, 555-563
.