寻找围绕红矮星运转的行星则相对容易，因为恒星的体积较小。
Looking for planets orbiting red dwarfs is easier because the stars are less massive.
因为这些星系的质量分布在更大的区域，它们每单位体积的恒星数量比传统星系要少得多。
Because these galaxies' mass is spread out over larger areas, they have far fewer stars per unit volume than do conventional galaxies.
首先，它太老了——甚至已经经过了红巨星阶段，红巨星阶段的恒星体积会迅速膨胀，并吞没近轨道的行星。
First, it's really old-past the Red Giant phase, when stars balloon in size and swallow up planets in close orbits.
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