Star Trails: A Weekly Astronomy Podcast · Single Malt Sky

Beyond the Frost Line: The Giant Planets of Our Solar System

·31 min·1 clip

Jupiter is so massive it's more than all other planets combined

Mars fades behind us. Drew takes the listener past the familiar inner worlds and into the colder part of the solar system, where the sun loses its grip on the scene and distance starts messing with your sense of scale. The asteroid belt gets cleaned up first. It is not a movie-style pinball field, just a huge, mostly empty region between Mars and Jupiter. Then the outer planets take over. Uranus stays odd: pale turquoise, faintly ringed, slow, and still hard to pin down. Voyager 2 still carries the weight here. Its 1986 flyby is the only close look, even after Hubble and large ground-based telescopes added more detail to the rings. At nearly 2 billion miles from the sun, daylight is closer to a bright point than a commanding presence. Time stretches too. With an 84-year orbit, Uranus has made only a little more than two trips around the sun since William Herschel found it in 1781. Neptune arrives by math before eyesight. The episode follows the prediction from Uranus's orbital oddities to the 1846 observation that confirmed another planet was pulling on it. Its blue is not fully solved. Methane helps, but the deeper color still points to chemistry and haze that are not settled. Neptune is cold and busy, with winds over 1200 miles per hour in air near minus 350 degrees Fahrenheit. Triton's backward orbit adds another wrinkle, since it likely came from the Kuiper belt. The episode then heads back toward Earth with a SpaceX launch-observing report, Night Watch notes, and sky advice for real backyards and balconies.

As heard by us

A steady outer planet tour that makes distance feel real.

Star Trails makes its outer planet tour feel concrete by staying with scale and distance. Mars falls away, the asteroid belt opens up, and the episode settles into the cold reach of the outer planets.

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Why you'd press play

If you want a patient tour from the asteroid belt to Neptune, start here.

Read the full recommendation in PlayNext →

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