Arecibo Message Live Distance

Instructions

The Arecibo Message is an interstellar binary radio message currently en route to M13. It was sent by the Arecibo Radio Telescope on November 16, 1974, and depicts information about Earth and humanity. Though largely symbolic, it is often regarded as the most serious attempt to contact alien life. This project shows, in real-time, the distance of the photons of the message from Earth. Since they travel at a constant speed (light speed), this project was surprisingly easy to make. The distances should be very close to their actual values. -Explanation of Each Counter- Light-Years: The total number of light-years the message has traveled. A light-year is the distance that light travels in a vacuum in one Julian Year. This can be calculated easily using the Days Since 2000 block. AU: The total number of Astronomical Units that the message has traveled through space. One Astronomical Unit is equivalent to the average distance between the Earth and the Sun. Miles: The total number of miles the message has traveled Kilometers: The total number of kilometers the message has traveled % of the way to M13: Gives the percent of its 25,000 light-year journey that it has currently completed. M13 refers to the message's destination, the Hercules Cluster. As the distance of M13 isn't precisely known, the counter could be slightly off. Farther from Earth than ____ stars: Estimates the number of stars that are within the distance that the message has traveled. In other words, it calculates about how many stars are closer to Earth than the message. It works by extrapolating from the number of stars known to exist within 20 light-years (109 stars) to make an estimate for any given radius. The equation's pretty simple: (Light Years / 20)^3 * 109 The Sun's Apparent Magnitude: This one's probably the hardest to understand. Basically, this calculates how bright the Sun would appear to an observer that’s as far away as the Arecibo Messsage. To represent the brightness of an object from a distance, astronomers use a system called Apparent Magnitude. Counterintuitively, lower numbers are brighter, and higher numbers are fainter. Here are some examples: The Sun is magnitude -26.74 from Earth The Full Moon is magnitude -12.7 Sirius, the brightest star, is magnitude -1.33 Polaris, the North Star, is magnitude 1.98 The faintest stars visible are about 6.5 The equation used to calculate the apparent magnitude of the Sun from the message's distance is -26.74 + log(AU^2) / 0.4 -More Information about the Message- The signal was targeted at M13 (often known as the Hercules Cluster), a globular star cluster about 25,000 light years away. It contains hundreds of thousands of stars. The message won't arrive for another 25,000 years or so (since radio waves travel at the speed of light). By that time, the cluster will be in a slightly different position, but the message should still arrive near the center. The broadcast was powerful enough that if any one of the star systems in the cluster hosts a civilization, the message should be detectable with a radio telescope comparable in size to the Arecibo Telescope. They would, however, have to be looking at the exact right place at the exact right time. The Arecibo Telescope collapsed in December 2020, but this message will vastly outlive it — and all of us. Even after it reaches M13 thousands of years from now, it will continue to travel further into space, preserving the legacy of humanity for eons.