Crossword-Solution: ALVAN 5 letters, 1 clue 🏆 scrabble score: 8

Alvan Clark, of Cambridgeport, Massachusetts, U.S., spent his leisure hour's in constructing small telescopes.[9] He was not an optician, nor a mathematician, but a portrait painter.

Alvan Clark was commissioned to erect a larger equatorial for Washington Observatory; the object-glass (the rough disks of which were also furnished by Messrs.

Nor did I choose to tell then, hoping that in some fortunate winter I might be able myself to repeat his process, greatly to the convenience of astronomers who have not Alvan Clark's resources at hand, or who have to satisfy themselves with glass lenses of fifteen inches, or even thirty, in diameter.

Haliburton, meanwhile, had brought out the Shubael refractor (Alvan Clark), and by night of Friday was in readiness to see what he could see.

While testing his stars for parallax; that astute observer was led to infer, from certain unexplained aberrations of motion, that various stars, Sirius himself among the number, are accompanied by invisible companions, and in 1840 he definitely predicated the existence of such "dark stars." The correctness of the inference was shown twenty years later, when Alvan Clark, Jr., the American optician, while testing a new lens, discovered the companion of Sirius, which proved thus to be faintly luminous.