This column was provided by San Benito County resident and amateur astronomer David Baumgartner as part of a local series on astronomy. Lea este articulo en español aqui.
Here on Earth, it is always important to know just how far away you are from certain places. But it’s not all that important, unless you think you may run out of gas before you reach home, or work. Now what about traveling in space, (do you see the smooth transaction there?) I would think running out of gas in the vast darkness of space could qualify for a really, really important thought before you take off. I believe it would be safe to say that anyone reading these opening remarks would never run into this problem. But who am I to know?
You may not find yourself traveling in space but if you find yourself reading or watching a program on T.V. on astronomy, here are some important facts that would be helpful for you to comprehend what they are talking about.
Distances:
Knowing how far away things are in space is very interesting and important. The trouble is, out in space distances are all so huge!
Width of the Earth: 8,000 miles.      Â
Earth to the sun: 93,000,000 miles. (Ninety-three million miles)
Light year: 6,000,000,000,000 miles. (Six Trillion miles)
The Width of the Earth: The Moon is about 30 Earth widths away. And the Moon is a bit more than ¼ of an earth’s width. The largest Planet, Jupiter, is about 11 earth widths. The Sun is 109 earth widths wide.
The Earth-to-sun distance: This is useful for measuring distances between objects in our solar system—distances from the Earth to another planet, from the sun to a comet, and so on. The fact is this unit is called: The Astronomical Unit.Â
Here is a table showing the distances of the planets outward from the sun, in astronomical units:
Mercury 0.4 Saturn 9.5
Venus 0.7 Uranus 19
Earth 1 Neptune 30
Mars 1.5 Pluto 39
Jupiter 5.2
In other words, Mercury is less than half our distance from the sun, Jupiter is about 5 times farther than us; and Pluto is nearly 40 times farther out.
The Light Year: Â Remember that a light-year is a distance, not a time. It is the distance that light travels in one year. Light is the fastest thing there is. It travels at a fantastic speed: 186,000 miles per second.
The light-year is used for talking about distances between the stars. The nearest star is a bit more than 4 light-years away. The star Sirius is about 9 light-years away, Regulus is 85; Deneb is very far away for such a bright star at 1,600. So when viewing Deneb and the light bouncing off your eyes that light left Deneb 1,600 years ago traveling at the speed of light. I know that sound a little confusing; Now sit back and pounder on that for a while. Feeling a little in significate, are you?
Clear Skies..
What’s up this month
Nov 02 Moon passes 4° north of Saturn
Nov 02 Moon passes 3° north of Neptune
Nov 05 Full Moon
Nov 05 Moon is at perigee (221,726 mile from Earth
Nov 06 Moon passes 5° north of Uranus
Nov 09 Mercury is stationary
Nov 10 Moon passes 4° north of Jupiter
Nov 11 Jupiter is stationary
Nov 12 Last Quarter Moon
Nov 12 Mercury passes 1.3° south of Mars
Nov 12 Moon passes 1.0° north of Regulus
Nov 17 Moon passes 1.2° south of Spica
Nov 17 Leonid meteor showers peaks
Nov 19 Moon passes 6° south of Venus
Nov 19 Moon is at apogee (252,706 miles from Earth)
Nov 20 New Moon
Nov 24 Mercury passes 1.1° north of Venus
Nov 25 Moon passes 0.4° north of Pluto
Nov 26 Jupiter passes 7° south of Pollux
Nov 28 First Quarter Moon
Nov 28 Saturn is Stationary
Nov 29 Mercury is Stationary
Nov 29 Moon passes 4° north of Saturn
Nov 29 Moon passes 3° north of Neptune