他们也能够看到宇宙中行成的第一个恒星和星云-这些恒星和星云古老而又遥远，它们发出的光已经被归入红外光谱。
They will also be able to see the first stars and galaxies that formed in the universe, which are now so old and distant that their light has been relegated to the infra-red part of the spectrum.
旋涡星云因为非常暗，难以得到它们的清晰的光谱。
Good spectra of the spiral nebulas are difficult to obtain because of their extreme faintness.
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