ϑ҈ꗗ (List of Observers) - 2003-04 Apparition
| Observer | Location | Telescope | Days | | Disks | Maps | Animations | Others | Measurements |
| Akutsu, Tomio | Tochigi, Japan | 32cm Refl. | 29 | | 235 | | | | | | | 116 |
| Akutsu, Hiroaki | Hokkaido, Japan | 28cm Refl. | 18 | | 84 | | | | | | | 91 |
| Asada, Hideto | Kyoto, Japan | 31cm Refl. | 10 | | 52 | 1 | | | | | | |
| Adachi, Makoto | Shiga, Japan | 31cm Refl. | 7 | * | 16 | | | | | | | 3 |
| Iga, Yuichi | Kyoto, Japan | 28cm SC | 18 | | 29 | | | | | | | 37 |
| Ikemura, Toshihiko | Aichi, Japan | 31cm Refl. | 45 | | 115 | | | | | 1 | 432 |
| Einaga, Hideo | Hyogo, Japan | 25cm Refl. | 119 | | 525 | | | | | | | 2504 |
| Ota, Satoshi | Okinawa, Japan | 32cm Refl. | 12 | | 17 | | | | | | | 136 |
| Oyamada, Hiroyuki | Kanagawa, Japan | 20cm Refl. | 4 | | 8 | | | | | | | | |
| Kazemoto, Akira | Kyoto, Japan | 31cm Refl. | 36 | | 100 | | | | | | | 485 |
| Kanno, Seiichi | Yamagata, Japan | 25cm Refl. | 22 | | 54 | | | | | | | | |
| Kumamori, Teruaki | Osaka, Japan | 60cm Refl. | 9 | | 15 | | | | | | | 164 |
| Suzuki, Takashi | Tokyo, Japan | 18cm MC | 16 | | 24 | | | | | | | 18 |
| Tomita, Yasuaki | Gumma, Japan | 25cm Refl. | 20 | | 27 | | | | | | | 23 |
| Nakai, Kenji | Hiroshima, Japan | 25cm MC | 11 | | 19 | | | | | | | | |
| Nakanishi, Hidekazu | Aichi, Japan | 30cm Refl./25cm SC | 9 | | 10 | | | | | | | | |
| Narita, Hiroshi | Kanagawa, Japan | 20cm Refr. | 64 | * | 104 | | | | | | | 8 |
| Niikawa, Masahito | Tokyo, Japan | 25cm SC | 5 | | 12 | | | | | | | | |
| Neichi, Mitsuyuki | Aomori, Japan | 25cm Refl. | 9 | | 17 | | | | | | | | |
| Hatanaka, Akitoshi | Mie, Japan | 40cm Refl. | 2 | | 3 | | | | | | | | |
| Hirabayashi, Isamu | Tokyo, Japan | 25cm Refl. | 1 | | 2 | | | | | | | | |
| Fukui, Hideto | Kyoto, Japan | 25cm Refl. | 91 | | 216 | | | | | | | 1472 |
| Horikawa, Kuniaki | Kanagawa, Japan | 16cm Refl. | 113 | | 58 | | | | | | | | |
| | | | * | 188 | | | | | | | 506 |
| Mishina, Toshiro | Kanagawa, Japan | 20cm Refl. | 68 | | 208 | | | | | | | 22 |
| Miyazaki, Isao | Okinawa, Japan | 40cm Refl. | 146 | | 357 | | | | | | | 3053 |
| Meiji Univ. | Kanagawa, Japan | 21cm Refl. | 7 | | 50 | | | | | | | | |
| Morita, Mitsuji | Shiga, Japan | 20cm Refl. | 9 | | 18 | | | | | | | 49 |
| Yunoki, Kenkichi | Osaka, Japan | 20cm Refl. | 121 | | 514 | 7 | | | 2 | 730 |
| Yoneyama, Seiichi | Kanagawa, Japan | 20cm Refl. | 49 | | 78 | | | | | | | | |
| Bates, Donald | USA | 25cm Refl. | 1 | | 1 | | | | | | | 20 |
| Cidadao, Antonio | Portugal | 28cm SC | 5 | | 38 | | | | | | | | |
| Colville, Brian | Canada | 30cm SC | 2 | | 13 | | | | | | | | |
| Grafton, Ed | USA | 35cm SC | 11 | | 21 | | | | | | | 272 |
| Ng, Eric | Hong Kong | 30cm Refl. | 19 | | 31 | | | | | | | 450 |
| Peach, Damian | UK | 28cm SC | 1 | | 1 | | | | | | | 25 |
| Pellier, Christophe | France | 18cm Refl. | 4 | | 20 | | | | | | | 37 |
| Sherrod, Clay | USA | 31cm SC | 16 | | 73 | | | | | | | | |
| Tatum, Randy | USA | 25cm/18cm Refl. | 8 | | 8 | | | | | | | | |
| Valimbert, Maurice | Australia | 35cm SC | 1 | | 3 | | | | | | | 25 |
| Total | | | | | 3364 | 8 | | | 3 | 10678 |
|
| * | visual observation |