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Figure Out Where You Are With Nothing But a Watch and Protractor –

Figure Out Where You Are With Nothing But a Watch and Protractor - 86

In a recent episode of MacGyver, Angus (yes, that’s his first name) finds his location in the desert using only a string, a protractor, and a watch. Is this actually possible? Basically, yes. (At least that’s what I told the show-runners as the technical consultant for the show.)

But you can do this, too. So now, for your super basic introduction to navigating the world. And don’t worry—this won’t be a full blown semester course on navigation, it’s just the basics.

Longitude

If you want to find out where you are on Earth, you need some type of coordinate system. Humans like to use longitude and latitude. You need to understand these in order to actually navigate. Both longitude and latitude can be thought of as circles (but not actual circles). Let me start with a basketball as an example. It already has some lines on it, so I just need to add some extra to make it look like this.

The lines that are already on the basketball are like lines of longitude. They all cross through the top (North pole) and bottom (South pole) of the basketball. This means that all these lines of longitude form circles that have the same radius—the radius of the Earth. Longitude is basically a way of breaking the sphere into 360 degrees. However, we don’t measure longitude all the way to 360°. Instead we have 0 to 180° East and 0 to 180° West. The 0° value is in Greenwich, England, and as you move West you would be increasing in longitude West.

OK, but how do you measure longitude? This is where a clock comes in handy. Yes, a clock. To understand this measurement, you need to know two things: The Earth is spherical (mostly spherical, offer not valid in all US States) and the Earth rotates so that it appears the sun travels around the whole sky every 24 hours (again, not exactly true, but close enough).

Now suppose you are in Greenwich (where longitude is 0°). At some time during the day, the sun will be at its highest position in the sky (which will not be directly overhead). We can call this 12:00 noon. If you are in Greenwich, you can set your clock to the sun. Now your clock also says 12:00 noon. Next, you travel westward all the way to New Orleans (since it’s close to where I live). You repeat the same experiment by waiting until the sun is at the highest point. But wait. Your clock doesn’t say 12:00 noon, it says 6:00 AM since it’s still set on Greenwich time. Since the Earth is spherical, the sun is at its highest point in Greenwich, but maybe it hasn’t even risen in New Orleans.

In fact, if you know the difference in time between Greenwich noon (what your clock says) and local noon (when the sun is at the highest point), you can find your longitude. This time difference is essentially your longitude. You just need to convert from hours to degrees (which I will skip). But notice how important it is to have a clock to determine your longitude. Really, there is no way around it—that’s why the Longitude Act of 1714 was so important. It established a prize for the development of an accurate and portable clock. OK, technically the prize was for a method to determine longitude—but really, a clock of some type is the only practical solution (unless you have GPS).

But wait! What if you want to navigate at night when you can’t see the sun? Yes, this method can still work. However, you need to know something extra. If you know the time a star rises (or the moon, or a planet) with respect to the time it would rise in Greenwich then you are all set. It’s the same idea as using the sun at noon. Of course. the problem with this method is that most people don’t memorize the rise-times of different celestial objects.

Measuring Lattitude

The lines of latitude also make circles around the Earth. However, they don’t all pass through the same points like the longitude values do. Instead, these are circles that are all parallel to the equator. If you look at my basketball above, the horizontal lines would be lines of latitude. Yes, I had to draw this on the ball.

Latitude is also measured in degrees but it starts at the equator which would be zero degrees latitude. As you move away from the equator (North or South), you increase your latitude degree such that New Orleans would be about 30°N. If you go to Sydney, Australia, you would have a latitude of 33.8°S since it is 33.8° below the equator.

OK, but how do you determine your latitude? This one is pretty straight forward—especially if you are in the Northern hemisphere. In short, you just need to measure the angular height of the North Star (Polaris) above the horizon. This works because the North Star is almost directly in line with the Earth’s axis of rotation. So, if you were at the North pole (and hopefully on ice), the North Star would be directly overhead with an angle of 90° above the horizon. If you traveled to the equator, the North Star would be exactly on the horizon and you would be at 0° latitude.

What about the Southern hemisphere? Yeah, that’s a small problem. Unlike the Northern hemisphere there isn’t a star right on the axis of rotation. Instead you just have to approximate the location of the celestial South pole by looking at other constellations.

Finally, how do you get this angular height of the North Star? That’s where the protractor comes in play. Here’s what you do. Take a string with a weight to act as a plumb bob. Now hold the protractor upside down and aim the straight part towards the North Star. Boom. That’s it. The plumb bob will hang at the angle reading for your latitude. Now you aren’t lost.

Note that with my DIY sextant (and most others), the string would point to a value on the protractor that is not the angle above the horizon. Actually, you would have to take your angle measurement and subtract from 90° to get your latitude. Also, there is a straw on top of my protractor to assist with the aiming—and it looks cool.

Of course both of these methods work, but the key is precision. For latitude, just a 1° difference in measurement means a distance of 69.1 miles or 60 nautical miles. In fact, the nautical mile is defined by the size of 1 minute of a latitude (where there are 60 minutes in 1 degree). This means that the better your angle measurement, the better you will know your actual location. Sure, a protractor works, but a sextant does this even better. A sextant is essentially just a much better protractor.

That’s it. That’s the basics of finding out where you are on Earth. But there are many other cool and fun details; if you want to learn more, I can recommend this nice online course from Vanderbilt University—AstroNavigation (it’s free).

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Planet Earth

Polar vortex: “wild” winter is coming in the US, Northern Europe and East Asia after the 16th of January

Polar vortex: "wild" winter is coming in the US, Northern Europe and East Asia after the 16th of January 99

In the upper atmosphere above the North Pole, experts saw a rapidly swirling vortex of cold air that could bring severe frosts to the United States, Northern Europe and East Asia. Serious cold snap and snowy weather are expected after January the 16th.

Snowfalls and a cold snap hit South Korea since the start of 2021, hitting historic snow maximums and temperatures. In the country, for the first time since 1964, television and newer communications are sending people cold snap warnings:

The situation is similar in Japan, where a new snow storm hit historic highs:

On January 7, the thermometer In Beijing dropped to -20 degrees Celsius, breaking the 1966 record. In other regions of China, the temperature is also not sugar, and you can only move around in special uniforms:

The cold even reached Taiwan, where the temperature in some areas dropped below freezing point, snow poured down and people realized that rice terraces can be used as a ski jump:

Even more snow went to Spain, where on January 6, 2021, a temperature of -34.1 ° C was recorded – the lowest on record. After that, a snow storm hit the country, which has not been seen for 80 years:

The same thing happens in Canada and in the northern states of the United States:

It seems that after a stratospheric warming, the subpolar vortex began to split:

The vortex itself is a standard phenomenon. However, this time experts were surprised at his movement. It is possible that in the near future it will be divided into two parts. 

Scientists associate the strange behavior with the changed climate in the Arctic, which has become warmer. From September to December, the amount of ice cover decreased significantly.

The polar vortex is a low-pressure region located in the stratosphere and filled with cold air. When the jet stream of air that holds the vortex weakens, the low pressure area moves south. 

As the ice shrinks, more moisture will move inland. It will turn to snow, so snowfalls are expected. Snow, in turn, reflects heat, leading to a cold snap.

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Planet Earth

Hospital in Naples was evacuated after a new, huge sinkhole appeared

Hospital in Naples was evacuated after a new, huge sinkhole appeared 100

Eyewitnesses said they heard a loud crash at dawn when a huge hole in the ground formed outside the Ponticelli Ospedale del Mare hospital in eastern Naples.

Early in the morning of January 8, 2021, a sinkhole occurred in the parking lot of a clinic in Naples. The depth of the formed cavity is about 20 meters, the total area of ​​the hole is about 2,000 square meters.

No casualties were found at the scene; firefighters say the sinkhole “affected an area of ​​about 500 square meters” and engulfed several cars parked near the hospital.

As the press writes and as a little can be seen from the videos, rescuers and firefighters were running around the pit together with the governor of the area.  But who should be there in the forefront are Italian geologists, since Naples stands in the very center of the volcanic system known as the Phlegrean Fields.

If the surface collapsed, moreover – the surface reinforced with concrete and reinforced from below with some kind of communications, then we are talking about serious soil deformations caused by the activity of magma.

Italy has been in doubt since the summer of 2020, because swarms were observed there in very atypical places in May, and according to the forecasts of old Italian seismologists, who had witnessed many strong earthquakes, it should have boomed in the August region.

Fortunately, nothing bad happened to Italy and there was no big earthquake. But, since there are swarms, it means that something is being prepared, the magma is gathering strength. 

Following this particular sinkhole event – an obvious sign that a major earthquake in Italy is already very close.

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Planet Earth

A new great pandemic cycle has begun (again) in China

A new great pandemic cycle has begun (again) in China 101

In the first months of 2020, the whole world with a certain fright followed the events unfolding in China, where people fell on the streets during the day and astronauts wandered, and in the evening crematoria began to smoke. And now, with the onset of December, the cycle seems to be repeating itself.

Shunyi area in Beijing, where the authorities announced “wartime status” the day before. As you can see in the videos, thousands of people are lined up in the queue for mandatory testing:

Dalian city, where “wartime” is also declared. Neighborhoods are blockaded, people are walled up in entrances, familiar characters of George Lucas roam the streets:

https://twitter.com/UndergroundSilk/status/1341741036297723905?ref_src=twsrc%5Etfw

Chinese ‘rescuers’, before performing a combat mission:

Chengdu City:

Daluo Port, Yunnan – tourists came for adventure and they received the ‘time of their life’ after leaving the ramp:

If something happens in Beijing, it does not mean that tomorrow the same will happen everywhere. However, the trend towards such dynamics is observed and, as the practice of the first wave of the pandemic has shown, all countries and people, to one degree or another, have taken into account the ‘Chinese experience’. 

Therefore, one must think that everything will now be in peace, as in spring – a new global round of the fight against the Covid has begun in China, a new great pandemic cycle!

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