Art and Architecture - The remains of the city of Persepolis, the ceremonial capital of the Achaemenid Empire, located in Iran. The earliest remains date to 515 BCE. Captured by Alexander the Great in 330 BCE, Persepolis was destroyed in a fire that same year, though whether it was an accident or a deliberate act of revenge is still debated.
35 years later, Voyager spacecraft nearing the edge of the solar system
In the fall of 1977, NASA launched the two Voyager spacecraft, which were designed to study Jupiter and Saturn and then continue on to the limits of the solar system. Today, they are each more than 14 trillion kilometers from the sun and nearing the “bowshock,” the transitional region where the solar wind collides with gas from interstellar space. Within five years, the Voyager crafts should be completely clear of our solar system’s influence. That far, light must travel more than 30 hours from the sun before it reaches the spacecraft.
What’s especially interesting about the Voyager expedition is the backstory behind the mission. Rocket scientists around the time of Sputnik were trying to design a rocket that could overpower the sun’s gravitational pull, a very tough task. A trip of more than a few months using this brute force method was out of the question. Cue Michael Minovitch, who in 1961 set out to solve the three-body problem, the question of how gravity from both the sun and the Earth would impact a third body, in this case the spacecraft. Some of science’s greatest minds, including Newton, were stumped by the task. However, with the use of one of the first computers, Minovitch was able to demonstrate how exploiting the sun’s gravitational field to slingshot a spacecraft deep into space. One of Minovitch’s simulations used this slingshot approach to accelerate using the gravitational fields of the sun as well as Saturn, Jupiter, Uranus and Neptune. The planets were only on the same side of the solar system in 1977, and the same opportunity wouldn’t present itself again for 176 years. Scientists luckily realized the potential in Minovitch’s idea, and launched the Voyager crafts with enough power to last for decades in space and with instruments to study the solar system’s furthest reaches. Today, although the signal from the spacecraft represents only a billionth of a billionth of a billionth of a watt once it reaches Earth, the ships keep sending back data and contribute to new discoveries.
Twenty years from now you will be more disappointed by the things that you didn’t do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover.
Don’t say anything, because I see that you understand me, and I am afraid of your understanding. I have such a fear of finding another like myself, and such a desire to find one. I am so utterly lonely, but I also have such a fear that my isolation be broken through, and I no longer be the head and ruler of my universe. I am in great terror of your understanding by which you penetrate into my world; and then I stand revealed and I have to share my kingdom with you.