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BAA Observing calendar

Uranus at solar conjunction

Wednesday, 2018, April 18 - 15:03

Dominic Ford – originally published on

From our vantage point on the Earth, Uranus will appear very close to the Sun in the sky as it passes around the far side of the solar system from the Earth.

At closest approach, Uranus and the Sun will appear at a separation of only 0°31', making Uranus totally unobservable for several weeks while it is lost in the Sun's glare.

At around the same time, Uranus will also be at its most distant from the Earth – receding to a distance of 20.90 AU – since the two planets will lie on opposite sides of the solar system.

If Uranus could be observed at this time, it would appear at its smallest and faintest on account of its large distance. It would measure 3.4 arcsec in diameter.

Over following weeks and months, Uranus will re-emerge to the west of the Sun, gradually becoming visible for ever-longer periods in the pre-dawn sky. After around six months, it will reach opposition, when it will be visible for virtually the whole night. A chart of the path of Uranus across the night sky can be found here, and a chart of its rising and setting times here.

The position of Uranus at the moment it passes solar conjunction will be:

Object Right Ascension Declination Constellation Angular Size
Uranus 01h45m40s +10°21' Pisces 3.4"
Sun 01h44m +10°50' Pisces 31'51"

The coordinates above are given in J2000.0.

The details of this observing event were provided courtesy of