8:37

Forklaring af årstiderne

3:20

Phases of moon explained using an orrery

2:08

How the Movement of the Earth and Sun Cause the Days, Seasons and Years

3:16

Seasons of the year | What Causes Seasons | Seasons on Earth | How Seasons change on Earth

10:22

Drone expert explains what he thinks is behind drone sightings

3:04

Årstiderne - efterårsjævndøgn - vintersolhverv - forårsjævndøgn - sommersolhverv - astronomi

14:56

Solens udvikling - Hydrostatisk ligevægt og fusion

14:37

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