After eight more years of fruitless searches, most astronomers assumed that there were no more and abandoned any further searches.

Because massive stars are thought to gather at a globular cluster's core, astronomers assumed that most newly minted white dwarfs dwelled near the center.

Certain astronomers now incorrectly assume that everything about our circumstance must be unspecial, insignificant, and just plain mediocre.

Since 1986 DA is apparently made of metal, astronomers assume it has much the same composition as metallic meteorites that reach Earth's surface.

In any case, this more expansive cosmic view is a far cry from that in the beginning of this century, when astronomers assumed the Milky Way was all there was, the universe entire.

In discussing the new findings, astronomers assumed a universe with an age of about 14 billion years, approximately the age of some of the oldest known stars.

When 51 Pegasi b, the first planet found around a star still undergoing fusion, was discovered, many astronomers assumed it must be a gigantic terrestrial, as it was assumed no gas giant could exist as close to its star (0.052 AU) as 51 Pegasi b did.

Since neither was present before the explosion, astronomers assume they both arose from the same blast, but how this could happen is a mystery.

Many astronomers, for convenience, split the difference and assume an estimate of 15 billion years.

Prior to that time, astronomers had assumed that nebulae were simply unresolved groups of stars.