Re: [guide-user] Ephemeris for Huyabusa-2

Bill Gray Dec 2, 2015

Hi Ted,

Try putting this file in your Guide folder :

This resembles your existing 'probes.dat' file, but it includes WT1190F
(the bit of space junk that recently re-entered just south of Sri Lanka;
details at ) and Hayabusa 2.

You can also get a geocentric ephemeris, with magnitudes, at

and, with a bit of effort, topocentric ephemerides via JPL's Horizons
system :

except that the Horizons ephems don't provide magnitudes. And the
magnitudes provided by Guide and/or my ephemeris page are not particularly
trustworthy; they use the magnitude relationship derived for asteroids.
I just got an e-mail from Luca Buzzi in Italy, who was unable to find
the object in images going to mag 20, so it's a good bit fainter than
the ephemerides suggest.

However, it's also getting closer rapidly, and therefore brightening
rapidly. So you may get a better look at it than Luca. Good luck, and
if you get positions and/or a magnitude estimate, please let me know!

-- Bill

On 12/02/2015 02:00 PM, Ted Blank tedblank@... [guide-user] wrote:
> Is there a file with the ephemeris for Huyabusa-2 available in a format Guide9 can accept? I'd like to be able to generate an animation trail for Huyabusa-2 to more easily understand how far it will move each minute.
> I have not tried finding / tracking comets or other fast-moving objects with Guide yet, but I'd like to try to take a few tracked time-exposures of the sky in the area of the spacecraft, maybe 30-second exposures a few minutes apart. In such a photo, after stacking, the stars should be very bright but immobile, and the spacecraft should appear as a series of evenly-spaced dots.
> (Gordon Garrad was able to image Cassini on its Earth fly-by back in the late 90's using a similar technique).
> If you have the ability to take photos of Huyabusa-2 using the above technique, please try it, the results are very interesting.
> Thanks!
> Ted Blank