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APPENDIX
As of Dec 1, 1999, 118 near-Earth asteroids have been discovered with H > 22 (Minor Planet Center Website and NEODys Website). The detection of small near-Earth asteroids has greatly benefited from the use of CCDs in asteroid surveying. All but one were dicovered by this means and all since 1990. The 15 month period ending Dec. 1, 1999 witnessed the discovery of 36 H > 22 objects. Physical and observational data is given for this subset in Table IV. In order to employ 1 to 2 meter class telescopes for fast rotator studies, objects must be brighter than V = 18 to provide sufficient S/N with short exposures. Roughly half (19 of 36) were brighter than V = 18 after discovery. The window of oppurtunity after discovery for physical study can be short and ranged between 1 and 19 days with a mean of 8 days. Maximum brightness occurred between 9 days before and 26 days after discovery with a mean of 4 days after discovery.
Prospects for predicted returns are discouraging. Only one small near-Earth asteroid will have a return conducive to light curve work during the next 5 years. 1993 VD may brighten to 
in October of 2002 though its orbital uncertainty will necessitate that it be rediscovered by a wide-field survey. If the current rate of discovery continues, nearly a dozen or more objects will be well placed for study during the normal course of scheduled observing each year. Unlike much slower rotating objects, short period light curves can be well determined in only an hour or two making study of these objects a small drain on observing resources. The necessary condition is an ability to schedule and perform observations on a short notice, often within a few days after discovery.
Acknowledgements
The work at Ondrejov has been supported by the Grant Agency of the Academy of Sciences of the Czech Republic, Grant A3003708, and by the Grant Agency of the Czech Republic, Grant No. 205-99-0255.
References
Asphaug, E., and D. J. Scheeres 1999. Deconstructing Castalia: Evaluating a postimpact state. Icarus 139, 383-386.
Farinella, P., D. Vokrouhlický, and W. K. Hartmann 1998. Meteorite delivery via Yarkovsky orbital drift. Icarus 132, 378-387.
Harris, A. W. 1979. Asteroid rotation rates II. A theory for the collisional evolution of rotation rates. Icarus, 40, 145-153.
Harris, A. W. 1994. Tumbling Asteroids. Icarus 107, 209-211.
Harris, A. W. 1996. The rotation rates of very small asteroids: Evidence for "rubble pile" structure. Lunar and Planetary Sci. XXVII, 493-494.
Harris, A. W., J. W. Young, E. Bowell, L. J. Martin, R. L. Millis, M. Poutanen, F. Scaltriti, V. Zappalà, H. J. Schober, H. Debehogne, and K. W. Zeigler 1989. Photoelectric observations of asteroids 3, 24, 60, 261, and 863. Icarus 77, 171-186.
Landolt, A. U. 1992. UBVRI photometric standard stars in the magnitude range 11.5<V<16.0 around the celestial equator. Astron. J. 104, 340-371.
Love, S. G., and T. J. Ahrens 1996. Catastrophic impacts on gravity dominated asteroids. Icarus, 124, 141-155.
Melosh, H. J., and E. V. Ryan 1997. Asteroids: shattered but not dispersed. Icarus, 129, 562-564.
Ostro, S. J., P. Pravec, L. A. M. Benner, R. S. Hudson, L. Sarounová, M. D. Hicks, D. L. Rabinowitz, J. V. Scotti, D. J. Tholen, M. Wolf, R. F. Jurgens, M. L. Thomas, J. D. Giorgini, P. W. Chodas, D. K. Yeomans, R. Rose, R. Frye, K. D. Rosema, R. Winkler, and M. A. Slade 1999. Radar and optical observations of asteroid 1998 KY26. Science, 285, 557-559.
Pravec, P., and A. W. Harris 1999. Fast and slowly rotating asteroids. Icarus, submitted.
Steel, D. I., R. H. McNaught, G. J. Garradd, D. J. Asher, and A. D. Taylor 1997. Near-Earth asteroid 1995 HM: a highly-elongated monolith rotating under tension? Planet. Space Sci. 45, 1091-1098.
Tedesco, E. F., G. J. Veeder, J. W. Fowler, and J. R. Chillemi 1992. The IRAS Minor Planet Survey, Tech. Rep. PL-TR-92-2049. Phillips Laboratory, Hanscom AF Base, MA.
Whiteley, R. J., and D. J. Tholen 1999. The UH Near-Earth Asteroid Composition Survey: An update.", Bull. Am. Astron. Soc., 31, 1089.
Zappalà, V., A. Cellino, A. M. Barucci, M. Fulchignoni, and D. F. Lupishko 1990. An analysis of the amplitude-phase relationship among asteroids. Astron. Astrophys. 231, 548-560.
Zellner, B., D. J. Tholen, and E. F. Tedesco 1985. The Eight Color Asteroid Survey: Results for 589 minor planets. Icarus 61, 355-416.
Table I:
Telescopes, Detectors and Observers
| |
Telescope |
Detector |
Observers |
| 1 |
Catalina St., 1.54-m |
2k x 2k CCDa |
Hergenrother |
| 2 |
Ondrejov Obs., 0.65-m |
SBIG ST-8 CCD |
Sarounová, Kusnirák |
| 3 |
Hawaii, 2.2-m |
CCD |
Whiteley |
 binning and read out in a
 subarray, in order to get the faster readout times. |
Table II:
Observational Circumstances
| Date UT |
R.A. |
Decl. |
r |
 |
 |
Obs.a |
 |
Filter |
Errors |
| |
h m |
 ' |
[AU] |
[AU] |
[deg] |
|
[sec] |
|
[mag] |
| 1999 TY2: |
| 1999 Oct. 5.9 |
1 02 |
+05 35 |
0.0314 |
1.0313 |
4.3 |
2 |
9 |
none |
0.11b |
| 7.3 |
2 03 |
-16 17 |
0.0254 |
1.0221 |
27.5 |
1 |
15 |
none |
0.02b |
| 7.3 |
2 03 |
-16 17 |
0.0254 |
1.0221 |
27.5 |
1 |
15 |
R |
0.02 |
| 7.3 |
2 03 |
-16 17 |
0.0254 |
1.0221 |
27.5 |
1 |
15 |
V |
0.02 |
| 7.3 |
2 03 |
-16 17 |
0.0254 |
1.0221 |
27.5 |
1 |
15 |
B |
0.06 |
| |
|
|
|
|
|
|
|
|
|
| 1999 SF10: |
| 1999 Oct. 7.1 |
21 22 |
-34 38 |
0.0163 |
1.0072 |
62.1 |
1 |
15 |
none |
0.07b |
| 7.2 |
21 20 |
-34 54 |
0.0161 |
1.0069 |
62.7 |
1 |
30 |
R |
0.05 |
| 7.2 |
21 20 |
-34 54 |
0.0161 |
1.0069 |
62.7 |
1 |
10 |
none |
0.10b |
| |
|
|
|
|
|
|
|
|
|
| 1998 WB2: |
| 1998 Nov. 28.5 |
4 02 |
+31 03 |
0.0558 |
1.0415 |
9.7 |
3 |
60 |
b v p x v |
0.02 |
| |
4 02 |
+31 03 |
0.0558 |
1.0415 |
9.7 |
3 |
180 |
u |
0.02 |
b Errors are relative with respect to other points within the given night. |
Table III:
Characteristics of Monolithic Asteroids
| Minor planet |
q |
a |
i |
Rotation period |
Ampl. |
H |
Sizea |
Taxon. |
Ref. |
| |
[AU] |
[AU] |
[deg] |
[min] |
[mag] |
[mag] |
[m] |
|
|
| 1999 TY2 |
0.892 |
2.267 |
23.1 |
 |
0.68 |
 |
80 |
S |
(1) |
| 1999 SF10 |
0.953 |
1.270 |
1.1 |
 |
0.58 |
 |
60 |
|
(2) |
| 1998 WB2 |
0.820 |
1.983 |
2.4 |
 |
0.6 |
 |
120 |
S |
(3) |
| 1998 KY26 |
0.984 |
1.233 |
1.5 |
 |
0.30 |
 |
30 |
CBFGDP |
(4) |
| 1995 HM |
1.139 |
1.460 |
4.0 |
97.2c |
2 |
22.5 |
130 |
|
(5) |
q, a, i are the perihelion distance, semimajor axis, and inclination, respectively.
a Mean diameter estimated from the absolute magnitude; see referencesfor assumptions on geometric albedos.
b Period half of this value is not ruled out but not considered likely.
c Most likely solution.
(1) orbital data from MPC 36572/physical data from this paper,
(2) MPC 36570/this paper,
(3) MPC 33380/this paper,
(4) MPC 32089/Ostro et al. (1999),
(5) MPC 26191/Steel et al. (1997). |
Table IV:
H>22 Near-Earth Asteroids Discovered in September 1998 - November 1999
| Object |
H |
Vmax |
V<18 |
V<18 Disc. |
|
Ref. |
| |
[mag] |
[mag] |
[days] |
[days] |
[days] |
|
| 1999 VX25 |
26.7 |
18.7 |
0 |
0 |
1 |
(1) |
| 1999 VW25 |
25.3 |
19.0 |
0 |
0 |
0 |
(1) |
| 1999 VV25 |
25.0 |
17.8 |
2 |
2 |
0 |
(1) |
| 1999 VU25 |
24.0 |
19.1 |
0 |
0 |
-6 |
(1) |
| 1999 VK12 |
23.7 |
17.5 |
3 |
3 |
6 |
(1) |
| 1999 TV16 |
23.4 |
17.9 |
1 |
1 |
4 |
(1) |
| 1999 TU16 |
22.1 |
20.5 |
0 |
0 |
6 |
(1) |
| 1999 TN13 |
23.6 |
17.3 |
8 |
8 |
4 |
(1) |
| 1999 TM13 |
24.7 |
19.4 |
0 |
0 |
-1 |
(1) |
| 1999 TY2 |
23.1 |
16.0 |
7 |
7 |
5 |
(1,3) |
| 1999 SH10 |
22.7 |
15.7 |
19 |
11 |
-9 |
(1) |
| 1999 SF10 |
24.0 |
17.0 |
9 |
9 |
11 |
(1,3) |
| 1999 RK33 |
22.3 |
17.1 |
16 |
16 |
8 |
(1) |
| 1999 RJ33 |
22.2 |
16.4 |
14 |
6 |
-1 |
(1) |
| 1999 RZ31 |
23.8 |
16.1 |
12 |
3 |
-2 |
(1) |
| 1999 RP28 |
22.5 |
19.3 |
0 |
0 |
10 |
(1) |
| 1999 NW2 |
23.1 |
14.8 |
21 |
10 |
0 |
(1) |
| 1999 LD6 |
22.4 |
18.8 |
0 |
0 |
-9 |
(1) |
| 1999 LK1 |
22.1 |
18.0 |
0 |
0 |
-11 |
(1) |
| 1999 LJ1 |
22.2 |
19.1 |
0 |
0 |
-14 |
(1) |
| 1999 HC1 |
24.5 |
16.5 |
7 |
6 |
3 |
(1) |
| 1999 FR19 |
22.3 |
17.3 |
7 |
3 |
-1 |
(1) |
| 1999 FN19 |
22.5 |
15.5 |
10 |
10 |
26 |
(1) |
| 1999 FQ10 |
23.6 |
18.6 |
0 |
0 |
-7 |
(1) |
| 1999 FR5 |
23.4 |
14.5 |
13 |
4 |
-5 |
(1) |
|
Table IV:
- Continued
| Object |
H |
Vmax |
V<18 |
V<18 Disc. |
|
Ref. |
| |
[mag] |
[mag] |
[days] |
[days] |
[days] |
|
| 1999 CG9 |
25.2 |
17.5 |
7 |
1 |
-2 |
(1) |
| 1999 CQ2 |
27.3 |
17.9 |
1 |
0 |
-2 |
(1) |
| 1999 AO10 |
23.9 |
17.0 |
20 |
19 |
7 |
(1) |
| 1998 XN17 |
22.8 |
18.5 |
0 |
0 |
4 |
(1) |
| 1998 WD31 |
23.5 |
19.8 |
0 |
0 |
45 |
(1) |
| 1998 WB2 |
22.1 |
15.3 |
16 |
16 |
16 |
(1,3) |
| 1998 VD32 |
22.2 |
17.7 |
12 |
12 |
7 |
(1) |
| 1998 UM1 |
23.2 |
17.6 |
10 |
0 |
-7 |
(2) |
| 1998 UR |
23.0 |
19.0 |
0 |
0 |
5 |
(2) |
| 1998 SD9 |
24.2 |
18.3 |
0 |
0 |
0 |
(2) |
| 1998 RK15 |
22.3 |
19.8 |
0 |
0 |
3 |
(2) |
H, Vmax, V<18, V<18 Disc., and
are the absolute magnitude, maximum V magnitude, days brighter than V=18, days brighter than V=18 since discovery and time interval between discovery and peak brightness (negative for peak before discovery), respectively.
(1) data from the Minor Planet Center's Unusual Minor Planet Site,
(2) data from the Near Earth Asteroid Dynamics Site,
(3) photometric data from this paper. |
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