The DE405 ephemeride is introduced as TRAO solar ephemeris system to support the apparent coordinates of planets after 2000. The time delay between planets and observer has to be regarded to get the apparent position of planet. Some fast algorithms about time delay are suggested to reduce the computing time. The CSI method is applied to run these algorithms on any O/S including both real-time and run-time machine.

• 김효령(한국천문연구원, 대덕전파천문대) | HYO RYOUNG KIM (Korea Astronomy Observatory, Taeduk Radio Astronomy Observatory)
• 노덕규(한국천문연구원, 대덕전파천문대) | DUK GYOO ROH (Korea Astronomy Observatory, Taeduk Radio Astronomy Observatory)
• 정현수(한국천문연구원, 대덕전파천문대) | HYUN SOO CHUNG (Korea Astronomy Observatory, Taeduk Radio Astronomy Observatory)
• 정재훈(한국천문연구원, 대덕전파천문대) | JAE HOON JUNG (Korea Astronomy Observatory, Taeduk Radio Astronomy Observatory)
• 조세형(한국천문연구원, 대덕전파천문대) | SE HYUNG CHO (Korea Astronomy Observatory, Taeduk Radio Astronomy Observatory)
• 안영숙(한국천문연구원, 대덕전파천문대) | YOUNG SOOK AHN (Korea Astronomy Observatory, Taeduk Radio Astronomy Observatory)