F2F Class Notes (Vicki)

Vocabulary

ride – xiang mu

Homework

Read the passage and write down your reflection

ā€˜Time waits for no manā€™ ā€“ or so the saying goes. We canā€™t stop time and we canā€™t control it, although sometimes, in our minds, we thinkĀ time fliesĀ ā€“ for example, when the weekend arrives, we feel itā€™s overĀ in no time! But if this year in particular feels like itā€™s passing more quickly than others have done, there could be a scientific explanation why.

Of course, we know a year is usually 365 days long. Clever scientistsĀ calculatedĀ this a long time ago. They also worked out that every four years, we need an extra day to keep our calendarĀ in syncĀ ā€“ this is called aĀ leap year. But 2021 isnā€™t one of those years, and yet itā€™s not behaving like a normal year. Scientists and astrophysicists haveĀ done the mathĀ and discovered the Earth is moving faster than it ever has in the last 50 years. This means that 2021 is going to be the shortest year in decades.

Apparently, this is because the Earth is spinning faster on its axis, quicker than it has done in decades, and the days are therefore shorter. But they are only short by a tiny amount ā€“ around 0.05Ā millisecondsĀ ā€“ so donā€™t panic if you havenā€™t noticed! However, long-term these millisecondsĀ add up. Astrophysicist Graham Jones and Konstantin Bikos from Time and Date told The Independent newspaper: ā€œIf the Earthā€™s rotation continues to quicken, we may at some point require aĀ negativeĀ leap second. If this happens, our clocks would skip a second in order toĀ keep up withĀ theĀ hurryingĀ Earth.ā€ Since 1972, 27 leap seconds have only been added to our time and none have been taken away.

This really is only of concern forĀ atomic clocksĀ ā€“ the mostĀ accurateĀ timekeepingĀ devices in history. Studying the Earthā€™s rotation and then subtracting or adding a leap second to these clocks can ensure they remainĀ alignedĀ and keep usĀ on time. But now, maybe we need to get a move on before this ā€˜shorterā€™ year is goneĀ in a split second!