北斗七星と北極星, the Big Dipper and the North Star
2025年11月19日、夜の3時ごろ起きた時にベランダから空を見たら晴れていて沢山の星が見えた。北のほうを見ると北斗七星と北極星が家の屋根越しに見えた。
On November 19, 2025, I woke up around 3 a.m. and looked out from the balcony. It was clear and I could see many stars. Looking north, I could see the Big Dipper and the North Star over the roof of my house.
柄杓の形をしている北斗七星の７つの星が見える。どちらから数えても４番目のδ星は三等星で暗い。他の６つの星は２等星なので明るく写っている。
The seven stars of the Big Dipper, shaped like a dipper, were visible. No matter which way you count, the fourth star, Delta, is a dim, third-magnitude star. The other six stars are second-magnitude stars and appear bright.
柄杓の先のα星から次のβ星に引いた線を約５倍延長した位置にこぐま座α星、ポラリスが見える。この星も２等星なので明るく見える。
Alpha Ursae Minoris, or Polaris, can be seen about five times the distance from Alpha of the Big Dipper at the tip of the dipper to the next star, Beta. This star is also second-magnitude, so it appears bright.
現在、このポラリスは天の北極に大変近い位置にあるので北極星となっている。地球の歳差運動のため、長い年月をかけて天の北極は移動するので、やがて他の星が北極星になる。
Currently, Polaris is located very close to the North Celestial Pole, making it the North Star. Due to the Earth’s precession, the North Celestial Pole will move over the course of many years, and eventually another star will become the North Star.