Days on Earth are getting longer, a team of experts has concluded, as they predict in the future there will be 25 hours in a day. Over the past 27 centuries, the average day has lengthened at a rate of almost two milliseconds (ms) per century. However, it will take about 6.7 million years to gain just one minute extra per day and we will have to wait about 200 million years for the extra hour. Study lead co-author Leslie Morrison said: “It’s a very slow process.”
These estimates are approximate, because the geophysical forces operating on the Earth’s rotation will not necessarily be constant over such a long period of time.
Leslie Morrison, retired astronomer with Royal Greenwich Observatory
Researchers at Durham University and the UK’s Nautical Almanac Office gathered evidence from historical accounts of eclipses and celestial events from 720BC to 2015. Mr Morrison, a retired astronomer with Royal Greenwich Observatory, said the earth’s orbit is not slowing as rapidly as first expected. It was previously estimated it will take 5.2 million years to add one minute to every day.