How fast should you go so that the sun never sets?

Many of us have pondered this question as we look at the sunset slowly lurking behind the horizon. As a child, it seemed that if you rush to the sunset on a bicycle, you can stop time and prolong the daylight. But in terms of physics and astronomy, to keep the sun from setting, you don’t need a bicycle, but something much more powerful and faster.

The earth rotates on its axis, and it is this rotation that creates the illusion of the movement of the celestial bodies. To “overtake” the sunset, the vehicle must travel westward at a speed exceeding the speed of rotation of the planet’s surface at a given point. Linear speed The rotation of the Earth is not constant and depends on the latitude at which you are located. It is a fundamental principle that turns a childhood dream into a challenging engineering challenge.

In this article, we will discuss in detail what numbers are behind this phenomenon, why an ordinary car is powerless against the force of nature, and what exceptions exist that allow you to enjoy an “eternal day” without supersonic speeds. We will also touch on the practical aspects of driving in the conditions of polar day and dusk.

The physics of the Earth's rotation and linear speed

To understand how fast we need to race, we turn to the geometry of our planet. The Earth makes a full rotation around its axis in 23 hours 56 minutes 4 seconds (star day), but for simplicity of calculations often use 24 hours. The equatorial circumference of the Earth is approximately 40,075 kilometers. If we divide this distance by the rotation time, we get the basic rotational speed.

At the equator, this figure is about 1,670 kilometers per hour. This means that the point on the equor is moving east at this speed. Therefore, to stay in place relative to the Sun (or to move toward it so that it does not change the position in the sky), you need to move westward at speed. 1670 km/h. This is a speed exceeding the speed of sound, which makes the task impossible for land transport.

But things change if you are not on the equator. The speed of rotation of the Earth's surface decreases as it moves away from the equator to the poles. This is due to the reduction of the parallel length. The formula is simple: the velocity is equal to the equatorial velocity multiplied by the cosine of latitude. That is why at the poles the rotation speed is zero, and there you can just stand still, watching the sun for six months.

Speed calculation for mid-latitudes

Most of the settlements in Russia and Europe are in temperate latitudes. Take the latitude of 55 degrees (about the latitude of Moscow or Copenhagen). The cosine of 55 degrees is approximately 0.57. Multiplying the equatorial speed (1,670 km/h) by 0.57, we get about 950 kilometers per hour.

Even at the latitude of St. Petersburg (about 60 degrees), where the cosine is 0.5, the required speed will be about 835 km / h. That’s still far beyond the capabilities of any production car. Supersonic aircraftsuch as Concorde Military fighters are capable of such speeds, but they are not designed for long-duration low-altitude flights in civilian mode.

If you are located further south, for example, at the latitude of Sochi (45 degrees), the required speed will increase to 1180 km / h. The closer you get to the equator, the faster you need to fly. This makes the concept of chasing the sun in a car physically impossible in most regions of the world. A normal car moving on the highway at a speed of 110 km / h, hopelessly behind the rotation of the planet.

• 🚗 At the latitude of Moscow (55° N) you need a speed of ~950 km / h.
• ✈️ At the latitude of Sochi (45° N) you need a speed of ~ 1180 km / h.
• 🌍 At the equator (0° N) a speed of ~1670 km/h is needed.

Polar Day: The Only Real Way

There is only one region on Earth where you can observe an “eternal day” just by being in motion at a comfortable speed for a car. These are the zones beyond the Arctic Circle (above 66.5 degrees north or south latitude). During the summer solstice, the sun does not fall below the horizon at all.

In such conditions, you do not need to develop supersonic speed. It is enough to simply move west at any speed, even 60 km/h, to compensate for the minimal shift of the sun or simply enjoy its constant presence above the horizon. Moreover, moving west on a polar day, you can artificially extend the “noon” by constantly adjusting your position.

However, it is worth considering that even in the Arctic, the sun does not stand strictly in place, it describes circles. So that it does not change the azimuth at all (does not move in a circle), the speed should still be high, but so that it simply does not go over the horizon, it is enough to be in the correct time window of the polar day. Murmansk, norilsk And the cities of Scandinavia are the perfect places to do these experiments.

⚠️ Attention: Driving in the polar day requires special care. Constant light knocks down circadian rhythms, causing fatigue and a decrease in concentration, which is comparable to the effect of lack of sleep.

Comparison of the speeds of transport and rotation of the Earth

For clarity, compare the capabilities of different modes of transport with the requirements of physics. The data in the table show how close a particular type of technology is to overtaking the sun at the latitude of Moscow (55° N), where the target speed is 950 km / h.

Mode of transport	Average speed (km/h)	Percentage of the desired speed	The result
Cyclist	25	2.6%	Sunset will come almost immediately.
Car (road)	110	11.5%	The day will last 15 minutes.
High-speed train	300	31.5%	Noticeable slowdown in sunset
Passenger plane	900	94.7%	The sun will almost freeze.

As you can see from the table, even modern high-speed trains, such as: Sapsan or TGVThey only develop about 30% of the required speed. Only jet aircraft are approaching the cherished figure. That is why when flying from Europe to America (west), passengers often notice that the flight lasts less than the time difference, or the sun does not set at all.

Why do planes fly faster than the Earth?

Airplanes fly in an atmosphere that rotates with the Earth. The speed of 900 km/h is the speed relative to the surface. If the plane were hovering in the air (which is impossible without constant thrust), it would be carried away into space along with the atmosphere, but relative to the ground it would move at the speed of the planet's rotation.

Practical tips for drivers at dusk

Although it is impossible to overtake sunset by car, drivers often face a situation where daylight hours are drastically reduced, especially in winter. Driving at dusk or at night requires a shift of attention and a change in driving style. Visibility It is a key safety factor.

First of all, it is necessary to properly adjust the light of the headlights. Make sure they don’t blind oncoming drivers, but light up a sufficient stretch of road. Dirty headlights lose up to 50% efficiency, so regular washing of optics is not a matter of aesthetics, but a matter of safety. Also check the adjustment of the light beam in the service.

Use all available review tools. Wipe not only the windshield, but also the side mirrors and headlight glass. The inner surface of the glass can also fog or be covered with a thin film of dust that scatters the light of the headlights, creating a “blinker” effect. Anticondensate The coatings and quality “janitors” make life much easier.

Psychology of perception of time on the way

The desire to “keep up with the sun” is often dictated by the desire to prolong pleasant moments or to have time to reach your destination in the dark. Psychologically, moving west really creates a sense of time slowing down. The sunset lasts longer, the shadows stretch more slowly.

For the driver, however, this can be a trap. Fatigue from long daylight or, conversely, the monotony of twilight dulls the reaction. The brain perceives the prolonged absence of light phase change as a signal to relax, although concentration is required at a constant rate. Circadian rhythms People are tuned to change day and night, and ignoring this fact leads to micro-sleep at the wheel.

If you plan a long journey across several time zones to the west, try to make stops every 2-3 hours. Even if it is light outside, your body needs rest. Use night-mode navigators to ensure that the bright screen does not knock your eyes off adapting to the dark.

Legal and technical limitations

Even if you abstract from physics and imagine a car capable of developing 1000 km / h, legal restrictions come into force. No public road is designed for such speeds. Attempting to achieve this speed on civilian transport will lead to instant loss of control and disaster.

There are also environmental and noise restrictions. Moving at supersonic speeds (if possible on the ground) would create a shock wave that destroys buildings and is dangerous to humans. Therefore, the question of how fast to go remains theoretical for motorists and practical only for pilots of supersonic aviation or astronauts.

⚠️ Attention: Exceeding speed even by 20-30 km / h on the highway significantly increases the braking distance. Do not try to compensate for the rotation of the Earth by accelerating - it is deadly.

Frequently Asked Questions (FAQ)

Can you overtake the sunset at the equator on a plane?

Yeah, it's possible. Passenger liners fly at a speed of about 900 km / h. At the equator, you need 1670 km / h, so a conventional aircraft there will not overtake the sunset. But at Moscow’s latitude (950 km/h), a modern jet plane could well fly faster than the Earth’s rotation, and for passengers the sun would “rise” from the west or stand still.

Where on Earth does the sun not set the longest?

At the North and South poles, the sun does not set for about six months (from spring to autumn). At this time, the polar day lasts there. At the latitude of the Arctic Circle (66.5°), the sun does not set only on the summer solstice (24 hours).

Does altitude affect the speed of rotation?

Yeah, but not much for normal heights. The higher you go, the larger the radius of the circle that needs to be described in 24 hours. Consequently, the linear rotation speed at altitude is slightly higher than at the surface. However, to achieve the effect of “sun stop” difference in several kilometers of height is insignificant compared to the required speed.

Why does the sun appear red at sunset?

This is due to the scattering of light in the atmosphere. When the sun is near the horizon, its rays pass through the thicker layer of the atmosphere. The blue spectrum is scattered more strongly, and long red waves reach our eyes. This phenomenon is called Rayleigh scattering.