topic 3 Flashcards
what are tidal buldges?
on earth these forces pull the oceans towards and away from the moon. these higher section of water called tidal buldges.
how does the sun have an effect on the tides?
spring tide and neap tides
when the sun,moon and eath are alinged it results in particular high or low spring tide.
when the moon and sun are at a right angle, they poduce neap tides.
what is the precision of equenoxes?
Earth’s axis wobbles slightly like a spinning top. This means that the Vernal Equinox is getting slightly earlier each year. This is called “Precession of the Equinoxes”.
what is “First point of Aries” ?
The point at which the Sun crosses the ecliptic at the Vernal Equinox
what did Eratosthenes calculate?
Eratosthenes calculated the circumference of the Earth over 2200 years ago.
what did Aristarchus of Samos calculate?
Aristarchus of Samos calculated the relative diameter of the moon.
what is the rule thumb?
Aristarchus decided the moon was about the size of his thumb held out at arm’s length.
