Through the short-period variability survey program, we obtained time-series BV CCD images for 1.5° X 1.0° region around the young open cluster NGC 457. As a result, we have detected 61 variable stars including 31 new ones after checking light curves of all stars by eyes. The 61 variable stars were included 14 δ Scuti variable stars, a β Cephei variable star, 10 variable Be and slowly pulsating B stars, 13 eclipsing binary stars, 21 semi-long periodic or slow irregular variables and an RR Lyrae variable star, respectively. Many variable B-type stars were known through a well-defined zero-age main sequence to the β Cepheid region of NGC 457. Most of the variable B-type stars found this paper were known variable stars. But, 11 out of 14 δ Scuti variable stars were newly discovered. The new variable stars except for δ Scuti stars were 4 variable B-type stars, 5 eclipsing binaries and 11 semi-long periodic or slow irregular variables. We have performed frequency analysis for all δ Scuti stars, a β Cepheid star and an RR Lyrae star.

ABSTRACT
1. 서론
2. 관측 및 분석
3. 결과
    3.1. 색-등급도
    3.2. B형 변광성
    3.3. 식쌍성
    3.4. 장주기형 불규칙 변광성 및 RR Lyrae 변광성
4. 요약
REFERENCES

• 이상민(한국천문연구원) | Sang-Min Lee (Korea Astronomy and Space Science Institute)
• 박윤호(한국천문연구원) | Yoon-Ho Park (Korea Astronomy and Space Science Institute)
• 전영범(한국천문연구원/경북대학교) | Young-Beom Jeon (Korea Astronomy and Space Science Institute/Kyungbuk National University)