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One really exciting part of working with an asteroid program is that, on occasion, you might discover a new asteroid. In the first three months of 1998, I have been credited with seven new discoveries. One might set out specifically to discover asteroids, but my strategy is to search for known asteroids so that my time might prove useful and to trust to serendipity for any new discoveries.
There would seem to be two major factors to improving one's chances at making a new discovery: how faint can you detect moving objects, and how much area of the sky can you cover. The ability to detect faint objects is a function of your telescope aperture and your exposure time. Exposure times are somewhat constrained as moving asteroids leave trails on long exposures and do not build up the image as would fixed stars. I usually take 6 minute exposures for this reason (Typically, asteroid movements are on the order of 30 arcsecs per hour. Hence, 6 minutes = 0.1 hr => asteroid movement of 3 arcseconds which is about one pixel in my setup. Of course, exposures could be tailored for specific brightnesses and rates of movement.) With my setup (8 inch SCT, ST-7 camera), I can typically detect 18th magnitude objects in 6 minute exposures, but I limit my targets to 17th or so. The ability to cover lots of sky is a function of your camera's field of view and how many images you take. Your camera's FOV interacts with your telescope's focal length, as well. I found my first new discoveries only after I started using the MaxField Focal Reducer which gave me a field some 4x (by area) of my previous setup. Upon reviewing my various discoveries, I don't believe I would have found them with the previous setup (17x12 arcmin field vs 35x23 arcmin). While all of my discoveries have been brighter than 17th magnitude at discovery, it would appear that most new discoveries are much fainter than this. Of course, there are a lot of professional scopes in the 1-meter class that are now devoted to asteroid searchs. I even saw recently (April 1998) where a couple of new discoveries had been made at 25th magnitude! (with the 3.6m telescope on Mauna Kea and the 2.5m Issac Newton telescope). Nevertheless, for my personal planning, I have decided to go with a larger scope (10" vs 8") which will produce slightly smaller field of view (28x18 arcmin vs 35x23 arcmin). We will see how the discovery rate changes! Discovery constitutes identifying a previously unrecognized asteroid over two different nights. Two nights worth of data will not usually produce a very reliable orbit (unless the two nights are WELL separated in time), so it is usually worthwhile following the new discovery for a longer period of time, otherwise it might well become 'lost' again. To help with this Guide6 also comes with a neat little program Find_Orb that can be used to compute a preliminary orbit accurate enough to predict the new discovery's position for a few weeks or so from the intial data measured by Charon. As you get more and more data, the orbit can be refined for more and more accuracy of more and more time (say a year so you can find it again next year). The orbital elements from Find_Orb can be included in the data bases of Guide6 such that finder charts can be prepared. I suppose the ultimate thrill would be to follow a new discovery long enough to establish an orbit so reliable that the Minor Planet Center awards it a permanent number and the opportunity to name it. This would probably take a minimum of four years. On the other hand, there is always the possibility (maybe with a greater probability) that after you have refined your orbit sufficiently, the orbit mavens at MPC and elsewhere might be able to link up your measurements with those of another 'lost' object from long ago. This happened with two of my discoveries. I'm not sure of the rules of the game but in one case, my provisional designation was subsumed into the old designation and in the other, my new designation survived and the other was absorbed. At any rate, it is still good, solid, satisfying work. Below are listed the designations and orbital elements as computed by Find_Orb for my seven (to March 31, 1998) discoveries.Orbital elements: 1998AE Perihelion 1997 Dec 28.711053 TT Epoch 1998 Jan 7.0 TT = JDT 2450820.5 M 5.27931 (2000.0) P Q n 0.56834289 Peri. 324.13410 -0.13873379 -0.99020899 a 1.4434301 Node 133.83486 0.91353238 -0.13398829 e 0.1412096 Incl. 1.22828 0.38237615 -0.03915724 P 1.73 H 19.9 G 0.15 q 1.2396039 From 13 observations 1998 Jan. 3-15; RMS error 4.257 arcseconds Orbital elements: 1998DD24 Perihelion 1998 Jul 17.780207 TT Epoch 1998 Feb 28.2 TT = JDT 2450872.7 M 326.42524 (2000.0) P Q n 0.24052719 Peri. 134.10837 -0.79779490 0.59909934 a 2.5607073 Node 82.81282 -0.57087062 -0.71437255 e 0.3675390 Incl. 3.92122 -0.19398459 -0.36159623 P 4.10 H 15.3 G 0.15 q 1.6195474 From 5 observations 1998 Feb. 28-Mar. 1; RMS error 1.785 arcseconds Orbital elements: 1998DU Perihelion 1997 Jul 6.751847 TT Epoch 1998 Mar 8.0 TT = JDT 2450880.5 M 88.21336 (2000.0) P Q n 0.36116287 Peri. 110.53080 0.46030668 -0.85502853 a 1.9528430 Node 309.73858 0.65384390 0.50850353 e 0.0931815 Incl. 18.09515 0.60050472 0.10173678 P 2.73 H 15.7 G 0.15 q 1.7708742 From 21 observations 1998 Feb. 19-Mar. 20; RMS error 1.347 arcseconds Orbital elements: 1998DU7 Perihelion 1997 Apr 4.850321 TT Epoch 1998 Mar 8.0 TT = JDT 2450880.5 M 64.02113 (2000.0) P Q n 0.18988935 Peri. 347.81153 0.19168620 -0.95834899 a 2.9977976 Node 90.85770 0.91731623 0.09823802 e 0.0839982 Incl. 12.22432 0.34898041 0.26817251 P 5.19 H 13.2 G 0.15 q 2.7459878 From 25 observations 1998 Feb. 23-Mar. 29; RMS error 1.379 arcseconds Orbital elements: 1998EP11 (Linked to 1996 VB31) Perihelion 1998 Aug 22.398633 TT Epoch 1998 Mar 28.0 TT = JDT 2450900.5 M 323.72324 (2000.0) P Q n 0.24611330 Peri. 220.84588 -0.66425850 0.74686897 a 2.5218117 Node 7.70785 -0.61214984 -0.51988625 e 0.2104528 Incl. 13.26702 -0.42899093 -0.41461431 P 4.00 H 14.3 G 0.15 q 1.9910895 From 13 observations 1998 Mar. 26-29; RMS error 1.116 arcseconds Orbital elements: 1998FY2 (Identified as 1992 BF2) Perihelion 1998 Jun 26.646504 TT Epoch 1998 Mar 22.2 TT = JDT 2450894.7 M 346.26537 (2000.0) P Q n 0.14236971 Peri. 87.59927 -0.80140563 0.59407651 a 3.6323775 Node 128.83830 -0.57807740 -0.73950791 e 0.5252710 Incl. 5.11477 -0.15354326 -0.31654566 P 6.92 H 14.5 G 0.15 q 1.7243950 From 3 observations 1998 Mar. 22-22; RMS error 1.149 arcseconds Orbital elements: 1998GA (Linked with 1992 SO2) Perihelion 1997 Nov 29.720476 TT Epoch 1998 Apr 17.0 TT = JDT 2450920.5 M 35.70578 (2000.0) P Q n 0.25821455 Peri. 115.06993 -0.80592801 -0.59099348 a 2.4423932 Node 28.74034 0.51380331 -0.72740125 e 0.1156219 Incl. 4.14294 0.29408537 -0.34873217 P 3.82 H 14.4 G 0.15 q 2.1599990 From 12 observations 1998 Apr. 1-4; RMS error 1.048 arcseconds