2002 MS4 26/05/2018
*Prediction based on Gaia DR2*
Observation tips:
- Shadow moves from **East to West**;
- The nominal occultation time on the map, corresponds to the big red dot, the closest approach.
- Each red dot is separated by one minute;
- Dark gray is night and light gray is astronomical twilight (Sun at less than 18 deg below the horizon);
- *Absolute time accuracy is essential** (see important note below);
- Observations are requested from 16:30 to 16:40 Universal Time.
After the observation, please fill the form available on this link (form), and send it to ribas(at)on.br.
| Star J2000 coordinates: |
|
RA 18 44 01.652 DEC -06 39 09.212 |
| Day coordinates of the object: |
| RA 18 45 01.210 DEC -06 37 55.247 |
| Star V mag | 16.730 |
| Star R mag | 14.200 |
| Star G mag | 14.039 |
| Star K mag | 12.570 |
| Magnitude drop in R | 6.4 |
| Maximum
duration |
36
sec |
| Moon
| 91% illum. |
@
70 deg |
Important note:
*Absolute time accuracy is essential**
to connect all the observations together after the fact. Check the time of your computer with many sources (phone talked hour, different internet sites, ideally with a GPS). Its advised to check the registered time right after and right before the integrations, so if there is a drift, we can correct it by having the difference.
Beware of the dead time between the images: if you manage an exposure time of 1 sec (for example), but have your camera takes 2 sec to read the image, then there is a 67% chance that you miss the dis(re)-appearance of the star. So it's better to have, for example, a 4 sec integration, so you have 67% chance to get the occultation in one of your exposures.
