Make Helsinki and Tallinn visible from each capital by increasing the height of the TV tower antennas Peedu Tuisk Follow Dec 8, 2018 · 5 min read

An idea concept for increasing Finnish-Estonian common bond: FinEst Lights. :)

Estonians and Finns are close relatives, we’re both Finnic peoples, speaking Finnic languages. We can almost understand each-other, but not quite, leading to funny misunderstandings. We use the same tune for anthem and we helped each-other in the wars for independence.

By 2017 an estimated 100,000 Estonians were working in Finland and during the same year Finns made ca 1.7 million over-night trips to Estonia. Recently the topic of a tunnel connecting our capitals has become more serious, giving hope for a potential twin-city metropolis emerging with the combined populations of over 1.5m people. Simultaneously we’re moving towards further digital collaboration.

While departing from Tallinn airport on an evening flight it’s been surprising how visibly close Helsinki’s city lights look at night. They’re right there, just barely hidden behind Earth’s curvature. But what if we could always see how close our capitals really are to each-other? How might it change the social dynamic between our peoples if we could simply glance at the horizon and see that our friends and tribe-mates are right there, over the sea.

Tallinn and Helsinki are separated by about 80km of water, the Gulf of Finland. That’s too far for making out any of the city lights from ground level.

However, on both sides of the coast there’s a tall structure.

In Tallinn there’s the Tallinn TV Tower (height 314m), conveniently located slightly to the east of the capital, closer to Helsinki. And in Finland, there’s the Helsinki-Espoo FM- and TV-mast (height 326m), equally conveniently located to the west of Helsinki, closer to Tallinn.

The Helsinki-Espoo mast is the same controversial one that transmitted TV signals during the 1980s which reached northern Estonia, providing the Soviet-occupied Estonians a window to the West through Finnish television. Back then the mast acted as a metaphorical beacon of light for Estonians. And the Tallinn TV Tower is the first thing Finns see when arriving on a ferry, acting as a lighthouse.

If these two structures had just slightly taller antennas on top, both’s lights could be visible at night from each side of the coast. Perhaps they could even use the flag colors for lights. A blue and white combination on the Finnish side and a slightly different shade of blue, black and white shining on the Estonian tower. A variety of colors could be used for special and solidarity events.

Normally the lights remain behind the curvature of the Earth and hidden from our line of sight, but luckily the atmosphere can create a refraction effect, same as a straw visibly tilting in a glass of water. If we account for atmospheric refraction under Standard Atmospheric conditions we can calculate how tall the two structures would need to be for us to see the lights from our capitals on most nights.

The distance between the capitals and the structures is about 80km. If a person stood on a pier by the sea, at a height of about 3 meters then the masts would have to be ca 427m tall without taking atmospheric refraction into account and about 361m with atmospheric refraction accounted for. However, the average altitude of our capitals is higher.

Calculated using online calculator by Mick West of Metabunk.org. Direct link to interactive calculations here.

The average altitude is 17m in Helsinki and 9m in Tallinn. So if a person stood at about 10m from sea level and looked at the horizon at night, the lights on top of the masts would need to be at about 370m without atmospheric refraction and only 309m with refraction effect accounted for. That’s even lower than the current height of the towers! And indeed, during some special weather conditions the Tallinn TV Tower is actually visible from Helsinki’s higher points. But unfortunately the weather conditions are not always so perfect.

Actual photo of Tallinn TV Tower as viewed from Helsinki.

To guarantee the visibility of both masts on most clear nights it would help to increase the height of the antennas at the top of the structures by at least 40–60m to about 370m.