2021-07-09, 02:02 AM
I use https://cneos.jpl.nasa.gov/ca/ and https://spaceweather.com/ to watch for close passes.
2019 NB7 looks good but the time error window is huge. Most likely due to being lost after not many observations. I'm choosing 2021 NE because the error is small. Never mind that it's faint and going to be below our horizon as this is just an example of how to set one up.
Click the name and it will get it into Horizons where you can adjust location, Time Span, etc. From the previous table saw close approach at July 10 15:37UT. I'll let Horizons run a 48 hr ephem from July 9-11 00:00UT to see where it is in dark skies. See 4-9UT good window for two mornings. Use your IA to find when those positions are up - 9th transits 01:00CDT, 10th transits 02:35CDT.
Now go back and change ephemeris to elements and create an hourly elements set. I'll pick 07:00UT on 10th. Copy (Ctrl+C) one full hour of elements.
Now in SkyTools, choose "Data", Minor Planets, "Enter New Minor Planet", Paste. Add in the name & H from Horizons. Click OK.
Wait. Do not interfere with the process. My hourglass takes ~200 seconds to completely finish and clear. Wait!!
Now go back into ST Ephemeris (position) and do object search. Set up the Date to coincide with the time of observation, Period for 1 hour, Interval for 2 minutes. Be watchful of time (UT vs Local). Run. Times agree well with Horizons!
Now pick time and choose Interactive Atlas. Run some tracks there. Use your finder chart. If anyone can add ways to shorten this process, I will thank you now.
Kenneth Drake
2019 NB7 looks good but the time error window is huge. Most likely due to being lost after not many observations. I'm choosing 2021 NE because the error is small. Never mind that it's faint and going to be below our horizon as this is just an example of how to set one up.
Click the name and it will get it into Horizons where you can adjust location, Time Span, etc. From the previous table saw close approach at July 10 15:37UT. I'll let Horizons run a 48 hr ephem from July 9-11 00:00UT to see where it is in dark skies. See 4-9UT good window for two mornings. Use your IA to find when those positions are up - 9th transits 01:00CDT, 10th transits 02:35CDT.
Now go back and change ephemeris to elements and create an hourly elements set. I'll pick 07:00UT on 10th. Copy (Ctrl+C) one full hour of elements.
Now in SkyTools, choose "Data", Minor Planets, "Enter New Minor Planet", Paste. Add in the name & H from Horizons. Click OK.
Wait. Do not interfere with the process. My hourglass takes ~200 seconds to completely finish and clear. Wait!!
Now go back into ST Ephemeris (position) and do object search. Set up the Date to coincide with the time of observation, Period for 1 hour, Interval for 2 minutes. Be watchful of time (UT vs Local). Run. Times agree well with Horizons!
Now pick time and choose Interactive Atlas. Run some tracks there. Use your finder chart. If anyone can add ways to shorten this process, I will thank you now.
Kenneth Drake