Page 617 - 89 history of astronomy_opt

Vogel,[17] with the Potsdam spectrograph,
actually found that the luminous star is re-
ceding before each eclipse, and approaching
us after each eclipse; thus entirely support-
ing Goodricke’s opinion. There are many
variables of the Algol type, and informa-
tion is steadily accumulating. But all vari-
able stars do not suffer the sudden varia-
tions of Algol. There are many types, and
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