When you are camped out at 3,200 meters on the side of an expired volcano south of the Guatemalan Highlands, words such as outdoors, nature or even night-time take on a different meaning. I wake sometime after midnight from an uneasy sleep. The temperature inside the tent has crept above zero degrees, thanks to the collective body heat of six people lying shoulder-to-shoulder. There is condensation building on the inside walls. I really don't want to leave the tent, but eventually my bladder drives me out into the ice-cold darkness. The clouds have dispersed, leaving behind an opaque sky and the Milky Way. It spreads out above me like a giant blanket which somebody has thrown over the curvature of the earth. I resist the impulse to reach out for a touch. In this moment of absolute stillness, I am awash with a feeling of proximity which is both comforting and unnerving. Out here, up here, nature plays out on a scale which dwarfs everything I know. A soft rumble fills the air. I squint. Ahead of me, Volcán de Fuego, the Volcano of Fire, lies in darkness, its pitch-black outlines visible against the star-studded sky. Fuego is the reason we are here, why we spent six strenuous hours climbing its taller sibling, Acatenango. Fuego has been active for hundreds of years. In 2012, its eruptions were so severe, authorities evacuated 33,000 people from the area. I gingerly pick my way past the smouldering remains of the camp fire and head for a secluded spot not far from the tents. The cold is so fierce it scratches over my naked skin. Soon my stiff fingers fumble to re-organise the many layers of clothing when I catch a movement from the corner of my eye. Fuego is awake. And there is lava. A crimson fan has spread out over the crater as chunks of molten rock shoot up into the sky in slow motion. Gravity eventually takes hold and the lava rains down on the slopes, accentuating the outlines of the volcano. The soft rumble wafts over again and it's the only audible noise to come from this force of nature - as if added sound would somehow distract from the visual, almost graceful, spectacle. I stand transfixed for what seems like an eternity. Only when I'm sure the eruption is over, I reluctantly head back to the tent. I need to get back to sleep. In just a few hours we will attempt to scale the summit, to catch the sun rising over the Guatemalan highlands, and to catch Fuego spewing ashes and lava once more.