arcsecond

A unit of angle; 1/60th of an arcminute, or 1/3600th of a degree.

Japanese Meaning

角度の単位。1弧分の1/60、すなわち1度の1/3600に相当する。

Under ideal seeing conditions, the observatory's telescope resolved structures as small as 0.5 arcsecond.

理想的な観測条件下で、観測所の望遠鏡は0.5角秒ほどの構造を識別できた。

Sense（1）

A unit of angle; 1/60th of an arcminute, or 1/3600th of a degree.

arcseconds

（ plural ）