| 1. | A heavy star at the upper end of the main sequence has a rather different later history .
在主序上端的大恒星具有很不相同的晚年史。 |
| 2. | Hydrogen to helium conversion provides the prime source of energy for stars on the main sequence .
由氢向氦的转变是主序星能量的主要来源。 |
| 3. | As these luminous and massive stars exhaust their hydrogen fuel, they begin to depart from the upper end of the main sequence .
当这些亮而且质量大的恒星耗尽了氢燃料时，它们就开始从主星序上端脱离。 |
| 4. | And stars in this region are called main sequence stars
，位于此区域的星则称为主序星。 |
| 5. | In the h - r diagram below , our sun is now in the main sequence
在以下的赫罗图中，太阳正位于主序上。 |
| 6. | Tams , terminal - age main sequence
终龄主序 |
| 7. | The main sequence stage lasts for a long time in the life of a star
对于大质量的恒星，由于它们的核反应速率很快，大约 |
| 8. | Zero - age main sequence
零龄主星序 |
| 9. | It takes about 0 . 1 to 100 million years for the cloud to become a main sequence star
这个收缩过程需要十万至一亿年，才能演化成一颗主序星。 |
| 10. | After it reaches the main sequence , the star will stay there for millions to billions of years
一般恒星会在主序星阶段逗留一百万至一百亿年。 |
