This week’s challenge is all about things you admire, so I decided on something a little less..conventional. Do not adjust your set; that is a real human brain, preserved in epoxy and currently on display at the Exploratorium. Take step back and consider all that a human brain does. Controlling your body’s functions, from the senses and sleep to memories and sheer, raw emotion. Keeping you breathing and balanced. Reading this sentence and processing the little squiggles into letters and words, and thus their meaning. A complex organic machine connected via trillions of synapses. For all the dangers out there, it’s allowed us to become the dominant species on the planet. We survive, thrive, create, accomplish, and it’s all because these little clumps of matter are developed just enough to make it happen. Yeah, it’s worth admiration. A larger version is viewable here.
Hey, folks. Happy Leap Year!
…Yeah, okay, it’s not an actual holiday. But it does represent one of the most important and fascinating aspects about the Earth and our understanding of physics. It’s common knowledge that a year is 365 days; it’s what modern civilization uses to keep track of business performance, industry production, crop harvesting, population growth, radioactive decay, public transit, pizza deliveries, birthdays, Oscar acceptance speeches, and pretty much anything remotely affected by the passage of time. Needless to say, timekeeping is kind of important.
However, it’s inaccurate.
The 365 day per year model is based on the Gregorian Calendar, which was first instituted by Pope Gregory XIII in 1582. It was an update to the far older Julian Calendar, in an attempt to bring the actual day of Easter closer to the day the church thought it was supposed to be celebrated. It was shoehorned in at the end of February because, honestly, the Romans had a long history of treating the month like an afterthought. While altering the basis of time measurement must have been a huge headache for everyone involved – there are still several different calendars spanning various cultures, and Greece didn’t adopt the new calendar until 1923! – it also illustrated the big problem with timekeeping on Earth: it doesn’t divide into perfect increments. Earth’s orbit is 365.256 days. How do you add .256 of a day to a calendar? Hence why Leap Day happens every four years; the calendar skips over that .256, then multiplies by a whole number of those years to make up for it. .256 x 4 = 1.024, which is just enough to make an extra day and leftovers small enough that no one will really care…
For now, anyway.
Here’s the thing: How we measure Leap Years – and thus the passage of time – is going to have to change in the far future. The algorithm that the Gregorian Calendar uses is fine for our current civilization; it’s as accurate and easily applicable as it needs to be. But on long-term timescales – we’re talking tens of thousands of years – it won’t be able to keep up with the astronomy and physics it’s based upon. Thanks to the effects of the Moon’s gravity, Earth’s rotation is actually slowing down, creating longer days. We’ve already introduced Leap Seconds to make up for the discrepancies and inconsistencies in the planet’s rotation. That’s all assuming that nothing crazy happens with Earth’s orbit, or if it remains stable enough until humanity dies off and the sun goes red giant and destroys the planet in a few billion years.
…Happy Leap Year!
DNews breaks down one of the latest and biggest discoveries in physics. Seriously though, this is amazing. The folks running the LIGO (Laser Interferometer Gravitational-Wave Observatory) have pulled off something that Einstein could only predict in his lifetime. Now that gravitational waves have been proven to exist, we’re one more important piece closer to solving – or at least comprehending – the vast puzzle that is the universe. If there’s ever going to be a 21st century game-changer for astronomy, this is it.
MinutePhysics explains why building things to last is more complicated than you might think.
Derek at Veritasium explains why we perceive time faster as we get older.
DNews briefly explains the latest additions that complete the seventh row of the periodic table. Right now, IUPAC has given them temporary names: Ununtrium, Ununpentium, Ununseptium, and Ununoctium. Yeah, gotta love that impromptu Latin root lesson…Anyway, these new elements will get proper names later on, and hopefully the public will get to learn more about what they can do as well. What a way for the field of Chemistry to kick off 2016!
AsapSCIENCE explains why keeping your New Year’s resolution is more complicated than you think.