There’s nothing quite like hearing the music swell in Outer Wilds. The space exploration game is almost entirely self-guided, and the player would be just as welcome to sit and watch the passing planets in the sky as make some fundamental discovery about the nature of the universe.

But when a track kicks in, you sit up and pay attention. Something’s happening. And often, this music also reflects the themes of togetherness and connection in the game.

[Spoilers for Outer Wilds, a game really best experienced without knowing much about it at all.]

Locations get their own tracks: the homely banjo of Timber Hearth or the echoing song of Dark Bramble. Stumbling onto something new or important always has a cue that brings a sense of wonder alongside curiosity being paid off. And the minimalist track that indicates the end of a timeloop beats like a fast-ticking clock, but still feels like an invitation into the next go-around.

Other times, if you’re just exploring under your own steam, admiring the stars, it’ll be quiet. This was a deliberate choice by composer Andrew Prahlow.

“When there’s constant looping music in an exploration game like Outer Wilds, the music can lose importance and become wallpaper,” he explains. “To avoid that and make the music stand out, I crafted the music to follow the player’s sense of exploration.”

Prahlow explains that, because the soundtrack is so crucial to the experience, he worked closely with the game’s creator, Alex Beachum. Their first concepts focused on the difference between the Hearthian race and their Nomai precursors.

“The Hearthian style focuses on folk instruments, as they emote with music through instruments, and simple campfire melodies. I wanted to evoke a sense of nostalgia, a callback to games that used simple motif, especially the Zelda series,” he says. On the other hand, “the Nomais emote through their technology, so I created a lot of melodic sound design and deep textures for their soundscape, and wrote a melody and textures to resemble a piano being ripped apart in space.”

Without a featureless vacuum to record in, Prahlow had to get creative with evoking that particularly excellent image. “I combined many piano libraries, heavily edited, as well as recording my upright grand live, to create a unified but custom piano sound from many sources,” he explains.

Overlapping sounds like this are a big part of many of the game’s tracks. “For the ‘End Times’ music, I wanted to capture the synth sounds from eras of game music from the late 1980s through modern-day, hearing them as a unified sound,” Prahlow says. “I used analog, digital, and some NES emulated synths – this way I was able to combine all eras of modern game music into a huge pad, with a memorable, minimalistic melody.”

And the songs are often designed to overlap one another, too, particularly the Hearthian and Nomai themed tunes. It’s fitting, considering the game follows a plucky Hearthian sifting through the remains left behind by the solar system’s previous inhabitants.

And of course, the most affecting example comes at the very end of the game. Travellers flung across space, who have been playing their instruments solo on very different planets, suddenly come together as a single band, playing around a campfire in the dark.

“That main folksong was actually the second thing I ever recorded for the score, probably back in 2012 or 2013,” Prahlow says. “It’s based off of the main title, so that theme has been around since the beginning of Outer Wilds.” No wonder it feels familiar, creating a welcoming space despite the collapse that surrounds it.

This ending scene isn’t just soundtracked so that there isn’t an awkward silence, it deliberately invokes the game’s message of connection.

“Even back in the alpha and beta stages, [Beachum and I] always loved the idea of having them alone playing on separate planets, but really playing as a band all together,” explains Prahlow. “It creates a really cool concept of how we as humans can be emotionally connected no matter the distance. I love thinking about our purpose on this planet – that we live on in this massive expanding universe, and through music, it gives us all an opportunity to connect and make it feel a little more like home.”

It’s no wonder that Outer Wilds’ music is so connected to its themes when you consider how Prahlow describes his composing process in the same terms of wide-eyed curiosity and exhilaration as those encouraged by the game itself.

“My own excitement of exploration and discovery within these soundscapes has really helped me dive deeper and deeper into my own sound as a composer,” he says. “It’s so fun knowing that I can always continue to grow as a composer, and a person, through these textures that I spend a lot of my time working on. Ambient music is a sonic world that I’m able to dive into every day, not knowing what skill I’ll learn or new texture that I’ll find, and it makes me truly excited about being a living, breathing, human being.”