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Chris Daniel
Colwyn Bay, Conwy, UK
Sunset is later the further west you go, so travelling in that direction gives you a longer day than if you had stayed in one place. For example, if you decide to drive from Great Yarmouth in the east of England to Aberystwyth on the west coast of Wales, you will have an extra 23 minutes of daylight.
Close to the International Date Line, it is theoretically possible to achieve a 48-hour day and then miss a whole day. The date line runs from the South Pole, threading its way round island groups in the Pacific Ocean, then between Russia and Alaska and on to the North Pole. When it is midday in London, it will be midnight at the beginning of the same day 180 degrees to the west – that is, the east side of the date line – and midnight at the end of the day 180 degrees to the east – that is, the west side of the date line.
To achieve a 48-hour day, imagine standing on the ice near the North Pole a metre or so to the west of the date line when it is noon on a Sunday in London. Where you are, it will be midnight at the end of that Sunday and going into Monday morning. On the east side of the date line, it will be midnight on Saturday going into Sunday morning. If you stay in your position on the west of the date line for 24 hours, Earth will make a full rotation, taking you through Monday and back to your starting point as Monday evening finishes and Tuesday morning is just about to start.
Meanwhile, on the east side of the date line, Sunday is just ending and Monday morning will be starting. So at this point, if you step across to the east of the line, you will be back in Monday again. If you don’t like Mondays, you can hop back into Tuesday at any time. Otherwise, stay there for another 24 hours until midnight, then step back over to the west of the date line just as Tuesday on that side is ending and Wednesday morning is beginning. In this way, you will have had 48 hours of Monday and will have missed Tuesday altogether.
Alternatively, while you are on the west side of the date line and midnight approaches, bringing your first Monday to an end, it would be possible (since you are so close to the pole) to walk slowly westwards away from the date line – that is, clockwise round the pole – while Earth rotates at the same speed in the opposite direction under your feet. In this way, you will remain stationary in relation to the sun’s position and your local time will stay at just before midnight on Monday evening.
As Earth continues to rotate anticlockwise, the date line will reappear in front of you 24 hours later. When it does, just step over it so you are on its west side again and you will be straight into Wednesday having had a 48-hour Monday.
Guy Cox
St Albans, New South Wales, Australia
If I fly from my home in New South Wales to Perth I will have a 26-hour day. Actually, one can cheat with daylight savings, since New South Wales has it but Queensland, in the same time zone, does not, but maybe that doesn’t count.
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Close to the International Date Line, it is theoretically possible to achieve a 48-hour day and then miss a whole day
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Regarding skipping a calendar day altogether, thereby hangs a tale. Some years ago, when there weren’t non-stop flights from Australia to the continental US, planes went via Hawaii. So I had the experience of missing a Saturday entirely since I crossed the International Date Line at midnight. But that was the day of one of my closest friend’s wedding! “Sorry Geoff, your wedding day didn’t exist for me.” Needless to say, the happy couple still got their wedding present.
Katherine Ellis
Barnet, Hertfordshire, UK
I have certainly experienced the scenario mentioned in the question, and I expect it isn’t that unusual.
In 2003, I flew to New Zealand and back, and both times changed planes in Los Angeles. We therefore crossed the International Date Line (between LA and Auckland) in both directions. My recollection of precise timings is hazy, but I recall the following:
On our outward journey, we set off on a Sunday and arrived in LA at a time only a couple of hours after we left. We spent a couple of hours in the airport, then took off again (still Sunday) and arrived in New Zealand on Tuesday. We lost a Monday.
Returning, we left Auckland at around 5pm on Sunday evening. We arrived in LA at about 10 or 11am on Sunday morning, where we had a 10-hour layover (we were able to leave the airport and experience our “second Sunday”, compensating us for the loss of a Monday a couple of weeks earlier). We then left LA on Sunday evening, taking an overnight flight arriving in London on Monday.
It was quite a strange experience, and probably the closest I’ll ever get to time travel!
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