Earliest Sunset

Listen 05:37

Sunset comes at 4:35pm this week, then gradually later and later, though it won’t be until early January before we really start to see gains in hours of daylight.

5 weeks ago, astronomers across the world were surprised to find a sizable interloper zipping through the solar system. It’s not unusual to discover a new comet but it really raises eyebrows – and telescopes – when that object seems to come from an entirely different star system! Oumaumau’s trajectory, velocity, shape and suggested composition brand it as not being a comet, but an asteroid. Its shape, reflectivity and non-reaction to its close fly-by of the sun all point to the rockier options. Observers around the world dropped what they were doing to get the best possible view of this one because it seemed…well, odd.
The interstellar object is ten times as long as it is wide and reflects just 4% of sunlight. It’s traveling at a brisk 98,000 mph, a trajectory that suggests it comes from the constellation Lyra. This could be an interstellar asteroid – the first ever seen.

Mars and Jupiter own the pre-dawn sky this week.

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