A day at Uranus just got a little longer.

Scientists reported Monday that observations by the Hubble Space Telescope have confirmed it takes Uranus 17 hours, 14 minutes and 52 seconds to complete a full rotation. That�s 28 seconds longer than estimates by NASA�s Voyager 2 spacecraft in the 1980s.

A French-led team studied a decade�s worth of aurora observations at the ice giant to track its magnetic poles. That long-term tracking provided a more precise rotation period for Uranus, the seventh planet from the sun. From that distance, it takes about 84 Earth years for Uranus to orbit the sun.

�The continuous observations from Hubble were crucial,� lead author Laurent Lamy of the Paris Observatory said in a statement.

Lamy and his international team said this new approach can help pinpoint the rotation of any world with auroras and a magnetosphere.

Published in the journal Nature Astronomy, the findings come a few weeks before the 35th anniversary of Hubble’s launch. NASA’s space shuttle Discovery delivered the space telescope to orbit on April 24, 1990.

(AP)