This is how far human radio broadcasts have reached into the galaxy and it’s a laughably small distance

Key takeaways:

1. Our Milky Way is vast, spanning up to 180,000 light-years across, but it’s only one of an estimated 100 billion galaxies in the observable universe, highlighting our small place in the cosmos.
2. Humanity’s radio signals, representing our presence, have only spread about 200 light-years, forming a tiny “blue bubble” in the galaxy, meaning most potential alien civilizations wouldn’t even know we exist.
3. The discovery of electromagnetic waves began over 200 years ago, with major advancements by scientists like Ørsted, Faraday, Maxwell, and Marconi eventually leading to radio transmission.
4. Even if we assume advanced alien civilizations exist, they would likely be far beyond the reach of our earliest broadcasts, making detection of human signals by extraterrestrials unlikely.
5. The SETI Institute is listening for alien signals and broadcasting messages, yet the galaxy’s scale means we may need to keep trying for tens of thousands of years to have a realistic chance of making contact.

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Our universe fascinates us. But haven’t you ever wondered how tiny the signals we send in this huge space are? It’s a humbling thought. The Milky Way, as reported by Read in 2015, ranges in size from one galaxy to another, which dwarfs other galaxies. Curiously, our radio signals have traveled a mere fraction of this: only about 200 light-years.

In keeping with this stark reality, the Dark Sky Company’s Adam Grossman created a beautiful 3-D map of our Milky Way. A tiny blue dot on the map encircling Earth broadcasts how far our radio waves have traveled. This massive puzzle gets us to contemplate: Are We Alone?

The cosmic ocean is a difficult place to travel, in a galaxy of 100 billion — or perhaps even as many as 400 billion stars. Roughly a century ago, humanity began sending out radio waves into space. But that tale of discovery begins long ago, with pioneers in this journey like Hans Christian Ørsted and James Clerk Maxwell. What forced them to dive into the hidden energies of electromagnetism?

Marconi ended up making significant strides in long-range communication as technology advanced. Our radios play an infinite number of signals today. Still, when we examine much wider-known chunks of the galaxy, it is humbling to find out how narrow our grasp truly remains.

That’s kind of a worrying statistic, really, considering our radio waves only reach about 200 light-years out. There has to be another alien civilization capable of detecting this minuscule bubble. Isn’t it amazing and sad at the same time? The likelihood that anyone is even in the neighborhood is close, contextually speaking.

Think of playing darts on a giant Milky Way dartboard, if you will. There are millions of square inches in the expanse of the galaxy to potentially cover, so statistically, you would be hitting a direct match nearly zero percent of the time. The question remains: is our universe so largely empty?

Due to these constraints, groups such as the Search for Extraterrestrial Intelligence (SETI) labor day in and day out, scanning multiple corners of our universe. With the help of cutting-edge radio telescopes, they continue to search for signals back. But the Milky Way is so massive that it makes communication appear practically impossible.

In human terms, that means SETI would have to listen for tens of thousands of years just to catch an echo. Who has the attention span for that in a world of instantaneous results? Even if signals were detected, what would they even mean?

As Carl Sagan so aptly put it, we are but “a mote of dust” in the vastness of space. This is what our attempts at connection might actually be about. But even as we gaze at the stars, we must think of our home.

A question that we are only reminded of as we embark on this cosmic expedition: Are we looking after our own house or searching for others? And perhaps we first need to tend to our planet before asking upper realms for help. We need to be good caretakers of this land we have been entrusted with.

We human beings like nothing better than to be amazed at the stars while completely forgetting about the minute cycles of life occurring in our immediate area. Relatively paltry though our radio emissions may be, they define the celestial benchmark for an entire terrestrial world. Space is vast, and this balance represents the challenge humanity must face on a galactic scale.