IAO 2015, theory, β — Задача 5

*АСТРОНОМИЧЕСКОЕ ОБЩЕСТВО

EURO–ASIAN ASTRONOMICAL SOCIETY

Round Theo

Group β

язык language English

XX Международная астрономическая олимпиада

XX International Astronomy Olympiad

Россия, Татарстан, Казань 15 – 23. X. 2015 Kazan, Tatarstan, Russia

Theoretical round. Problems to solve · 15 октомври 2015 г.*

Условие

5. Spiral galaxy. A spiral galaxy consisting mainly of A7-A8 spectral class stars was discovered in the Southern Cross (Crux) constellation. The galaxy may be seen as oval of about 40 by 30 arcsec in the sky. The broadened H$\alpha$ line is observed at wavelengths approximately from 7054 Å to 7057 Å in the spectrum of the galaxy. Other lines in the spectrum are also shifted and broadened proportionally. Estimate the number of stars in the galaxy.

Решение

Оригинал в Архива: theo_beta.pdf