Fall Astronomy Week on September, 2018: PLEASE HELP!!!! Astronomy-moon phases?
Fall Astronomy Week 2018. 792050 Astronomy Astronomy and Astrology
The Moon is a sphere which travels once around the Earth every 29 days. As it does so, it is illuminated from varying angles by the Sun. At New Moon, the Moon is between the Earth and Sun, so that the side of the Moon facing towards us receives no direct sunlight, and is only lit by dim sunlight reflected from the Earth. As it moves around the Earth, the side we can see gradually becomes more illuminated by direct sunlight.
After a week, the Moon is 90° away from the Sun in the sky and is half illuminated, what we call First Quarter because it is about a quarter of the way around the Earth.
A week after this, the Moon is 180° away from the Sun, so that Sun, Earth and Moon form a line. The Moon is fully illuminated by the Sun, so this is called Full Moon. The Earth's shadow points towards the Moon at this time, but usually the Moon passes above or below the shadow and no eclipse occurs.
A week later the Moon has moved another quarter of the way around the Earth, to the Third Quarter position. The Sun's light is now shining on the other half of the visible face of the Moon.
Finally, a week later, the Moon is back to its New Moon starting position. Usually it passes above or below the Sun, but occasionally it passes right in front of the Sun, and we get an eclipse of the Sun.
The Moon's phases are NOT caused by the shadow of the Earth falling on the Moon. In fact the shadow of the Earth only falls on the Moon twice a year when there is a lunar eclipse.
Any good tips for making yourself fall asleep?
Relaxation is key. No tv, no texting or phone calls that can lead to emotions, so basically turn the phone off. Take a walk, a warm bath, curl up and read somthing. Dont think about going to sleep concentrate on your relaxation after a certain time of night as part of a routine. Watch what time you have caffinated beverages, and sugars, try to eat by 5 or 6 so your body isnt struggling to digest food and your trying to sleep. Take up astronomy, a nice walk in the cold air, gazing at a few constellations is relaxing to me.
Astronomy: Explain how it is that some stars never set in our sky...?
a) All stars, except those right on the equator, are circumpolar from some place in the world.
If you were at the north pole, you would see Polaris, the north star, overhead (give or take a half-degree of celestial latitude). All the other stars in the northern half of our sky would seem to roll around the sky, always at the same altitude, following paths parallel to the horizon. Stars close to the equator would follow paths closest to the horizon. Stars right on the equator, such as the Three Marias of Orion's belt, would stick so close to the horizon as to be practically out of sight.
At the south pole, the same would happen, except that this time it would be all the stars in the southern half of the sky that never set. The Three Marias would always stick to the horizon, just like at the north pole. Any star you could see from the south pole would always be invisible from the north pole (in our current era) and vice versa.
The closer you get to the equator from either pole, the fewer stars that are permanently above the horizon. At 15 degrees North latitude, for instance, only stars within 15 degrees of the north pole are permanently above your horizon. The north star, naturally, is one of them. Everything else, including the Big Dipper, sets at some time from 15 degrees North latitude.
At the equator, all the stars rise and set at some time of the year.
If you were at Buenos Aires, 34 degrees South latitude, there would be no northern stars permanently above the horizon, but now any star within 34 degrees of the south pole would never set. The Southern Cross is in this category, and it never sets from Buenos Aires.
b) No, that would be absolutely impossible.
Eclipses do not happen at random times. They occur only during eclipse "seasons." Each year, there are two eclipse seasons, about 25 weeks apart, or a little under six months apart. These eclipse seasons migrate through our calendar, so in some years there can be three eclipse seasons, in January, June and December.
In 2007, the eclipse "seasons" fell in March and late August/early September. The next one will be February 2008. You can see how two eclipses might fall five months apart. Three months apart, however, is impossible.
Eclipses occur only when sun, moon and earth are aligned in some order. Outside eclipse seasons, however, the moon passes above or below the line of the earth and sun, so that its shadow cannot touch the earth and vice versa. So, if you had an eclipse in April, then three months later the moon would pass so far above or below the line of the earth and sun that one's shadow cannot touch the other.
Hope this helps, hope the exam goes good.