The Color Purple

Listen 06:11

Newly discovered? A purple planet! Actually, the color suggestion is just speculation based on the planet’s expected chemical composition. The planet, called WASP-104b, orbits 4 million km from its yellow dwarf parent star every 1.75 days. 104b most likely has a potassium and atomic sodium atmosphere which gives its most compelling characteristic – it’s DARK.
One study suggests that it’s darker than charcoal. Measurements show 95 to 99% absorption of light from its parent star. Studies suggest that having one side permanently facing the sun makes it too hot for ice crystals to form – the primary atmospheric reflection mechanism in planetary atmospheres. Then the chemistry also absorbs light to a very high degree. Two other exoplanets are known to be this dark or darker, but accurate measurements are tough to get.

May Day is celebrated in many northern hemisphere cultures as the beginning of summer. This makes June 21 mid-summer and so matches the timelines for Shakepeare’s play, ‘A Mid-Summer Night’s Dream’. May 1 is a cross-quarter day between Spring and Summer. Sunrise is 6a and sunset is 7:55p for this latitude.

Saturday is the 57th anniversary of Alan Shepard’s historic suborbital flight, the first for a US astronaut. In answer to Yuri Gagarin’s orbital flight three weeks earlier that same year, 1961.

Venus is the evening star now for sure. Saturn rises just after midnight with mars following an hour later. This places the three across the southern sky at 5a. this week – the moon slides through the group from tomorrow through Sunday morning.

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