00589 C2007 08 06.08476 16 37 52.36 -08 48 57.4 14.6 V H68
00589 C2007 08 06.09271 16 37 52.40 -08 48 59.2 15.3 V H68
00589 C2007 08 06.09314 16 37 52.40 -08 48 59.4 14.8 V H68
00589 C2007 08 06.10058 16 37 52.44 -08 49 01.3 14.9 V H68
00589 C2007 08 06.10916 16 37 52.49 -08 49 03.5 15.2 V H68
At first, the numbers above may look confusing, but they are really simple to understand! Each line actually contains the name (or designation) of a minor planet, the date and time (in decimal form) the image was taken, the exact position of the minor planet, the estimated magnitude,telescope and CCD imager used, and the observatory code.
Each line is a position measured of a minor planet, and each line is a measurement of a different time. The five positions above were obtained from five separate images over a period of time. Let’s start by breaking down the first line.
Contents
Minor Planet Identification/Designation
00589 C2007 08 06.08476 16 37 52.36 -08 48 57.4 14.6 V H68
00589 – Reading from left to right, notice the first numbers are 00589. This can be the number, name, or designation of the object being measured. In this example 00589 is actually asteroid 589 (Croatia).
In this example, it is listed as 00589 since this is the format that the Minor Planet Center requires (at least five characters and no more than seven). If a report is submitted with only 589 in this section, the measurements may get rejected.
If the positions are confirming observations of an object listed on the NEO Confirmation Page as listed by the Minor Planet Center, these numbers will need to be listed exactly as the objects temporary designation (and these can greatly vary and contain numbers and letters).
Date and Time
00589 C2007 08 06.08476 16 37 52.36 -08 48 57.4 14.6 V H68
C2007 08 06.08476 – This group of numbers is simply the date listed in decimal format. C2007 is the year, 08 is the month of August, and 06.08476 is the day in decimal format. The software used to perform the measurements should make these calculations automatically (and the time should be within the nearest second).
The time should be “marked” in the image either at the beginning, the middle, or the end of the exposure. It is highly recommended that a form of “synchronization software” is used on the computer to synchronize the computer with at least one of the many sites on the web – and this should be done at least every three to five minutes! If your time is off on the computer, the positions will be off as well!
Right Ascension (R.A.)
00589 C2007 08 06.08476 16 37 52.36 -08 48 57.4 14.6 V H68
16 37 52.36 – This next group of numbers is R.A. (Right Ascension). Notice that these numbers are not listed as 16h37m52.36s. The h, m, and s, is not needed when submitting astrometry.
Declination (decl)
00589 C2007 08 06.08476 16 37 52.36 -08 48 57.4 14.6 V H68
-08 48 57.4 – The group of numbers following R.A. is Declination. Too, these numbers are not listed as -08d48m57.4s. Again, the d, m, and s are not needed for astrometry.
Magnitude or Brightness
00589 C2007 08 06.08476 16 37 52.36 -08 48 57.4 14.6 V H68
14.6 V – As we are nearing the end of the line, this next section is reserved for Magnitude. As mentioned earlier, V magnitude is simply the brightness (or dimness) of the minor planet being measured. The astrometry software will determine this by comparing known magnitudes of the surrounding stars and calculate a magnitude for the minor planet by using the magnitudes of the stars in the field.
Sometimes these numbers can greatly vary within a set of positions and this could be due to the software miscalculating the magnitude of the minor planet, or it could be a fast rotating minor planet which is oddly shaped and quickly rotating. See the photo of a lightcurve of a fast rotating Near Earth Object in this article.
The Observatory Code
00589 C2007 08 06.08476 16 37 52.36 -08 48 57.4 14.6 V H68
H68 – The last characters in the line of astrometry is the actual observatory code that obtained the observations of the minor planet. In this case, these positions were obtained from Observatory H68 (Red Barn Observatory).
When the astrometrist is prepared to step into this research and is ready to obtain their own observatory code, the Minor Planet Center will issue the code – once they approve the initial observations that have been submitted to them. Too, if work is performed from a Remote Observatory, any observations submitted must be designated with that observatory code.
