That also means that Hubble can't observe Mercury, Venus and certain stars that are close to the sun either.

With this he systematically observed Venus, Mars, Jupiter and Saturn.

But in the century or so that probes had been observing Venus, none had ever seen a volcano erupt.

Yet for the hundred or so years that spacecraft had been observing Venus there had been no recorded volcanic eruptions, until now.

They included unmanned flights to observe Venus and Mars, the development of militarily and commercially important weather and communications satellites and technical innovations in aviation.

During the encounter, all instruments were used to observe Venus and prepare for the following Mercury encounters.

In her years in the industry, Ms. Fennelly has had plenty of time to observe Mars and Venus in the workplace.

Led by James Melville Gilliss, it arrived in Chile in 1849 to observe Mars and Venus from southern hemisphere so as to improve solar parallax.

He also observed Venus and Mercury.

One of the easier hikes he led took us up Transit Hill, named for the 1882 scientific gathering to observe Venus.