This apparent disappearance lead some astronomers to consider the moon lost.

The astronomers have also considered more outlandish explanations.

When the telescope was first proposed in 1946, astronomers did not consider siting them abroad, he said.

The success of OAO-2 motivated astronomers to consider larger missions.

With the discovery of Pluto in 1930, astronomers considered the Solar System to have nine planets, along with thousands of smaller bodies such as asteroids and comets.

For this reason, the typical acceleration of any physical process is not the only parameter astronomers must consider.

When performing star counts, astronomers consider many different categories that have been created to classify a few stars that have been well studied.

As radar was being developed, astronomers considered its application in making observations of the Moon and other near-by extraterrestrial objects.

He decides to show us M13, which amateur astronomers consider one of the most exciting objects in the night sky.

Many amateur astronomers consider it one of the finest northern globular clusters, following only Messier 13.