384,400km.  However, since the Moon’s orbit is not perfectly circular (because orbits like that only exist in theory), this distance is only an average.  At its closest point (known as perigee), the Moon is 363,104 km from Earth and at its furthest point (known as apogee)it is 405,696 km away.  Incidentally, these distances are from the centre of the Earth to the centre of the Moon.  If you want the distance from surface to surface, you’ll have to take into … Continue reading →

Lunar eclipses are rather more common than Solar Eclipses, even though they have the same cause.  When the Earth, Moon and Sun are all positioned in a straight line, the Sun casts a shadow from one of the remaining two objects onto the other.  When the Moon is in the middle of the alignment, the Moon’s shadow is cast upon the surface of the Earth, and this gives us a Solar Eclipse.  When the Earth is in the middle, it’s … Continue reading →

William Herschel discovered Uranus, and it was completely by accident.  In 1781, while using one of his powerful home-made telescopes to survey a region of the sky in the constellation Taurus, he noticed that one star seemed a little larger than the rest.  When he checked up on it again a few days later, he found that it had moved which helped confirm that it was actually a new planet.  Although he tried to name it after his King, George … Continue reading →