Gravity is the force that attracts objects with mass towards each other. On Earth, it is what brings us back to the ground if we jump upwards. In space, it is what makes the Moon orbit the Earth, what makes the Earth and other planets orbit the Sun, and what makes the Sun and stars orbit the centre of the galaxy. According to physicists, there are only four forces in the universe, and gravity is the weakest by a ridiculously … Continue reading →
For as long as we have looked at the stars, we’ve known that sometimes a new star appears from nowhere. This has always been a big deal since it was well understood that the stars were eternally fixed in the sky, and could neither move nor change (with the obvious exceptions of 5 bright wandering stars that the Greeks called Planets). A new star was direct intervention from the gods so it was vital that the astrologers found the corresponding … Continue reading →
A supernova explosion is one of the most powerful releases of energy in the universe. When the largest stars run out of fuel and collapse, the implosion of their core rebounds with such power that the resulting explosion outshines entire galaxies for several weeks. All that remains is a tiny dense neutron star, surrounded by an expanding cloud of ultra-hot glowing gas which we see as a beautiful nebula. If the star was particularly massive, then the remains of … Continue reading →
Many, if not most, ancient and primitive societies worshipped the Sun as a god. Sun worship continues to this day in various guises around the world. This makes a lot of sense, because the Sun has a lot of the features in common with our various cultures’ gods. We are totally dependent on the Sun It is universally known, across all cultures from the most primitive to the most enlightened and sophisticated, that the Sun is the source of all … Continue reading →
Dear Urban Astronomer, I am embarrassed to admit that although I have heard a lot about the Hubble Telescope, I’m still not actually that sure about its purpose. Does it belong to NASA or just the world in general? Is it just a telescope that sends back picures or is it looking for extra-terrestrial life? How big is it? Is it a satellite or does it just travel for eternity into space? Is it solar powered or will it eventually … Continue reading →
