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Wednesday
Feb232011

For you early risers...

There's a great show coming to town. Get up early, like the sign says at dawn ans see the waining cresent moon and Venus.

 

Venus will be on the Moon's  lower left on the 28th, and then the next morning the upper right.

 

Our two brightest neighbours will be side by side. Well, close enough for sure.

Sunday
Feb202011

Obscure Joke of the Week

A philosophy student we knew
Just couldn't get into Lao Tzu
He couldn't see how
To put a "D" in the Tao
So he went back to reading Camus.


- Posted using BlogPress from my iPad

Sunday
Feb202011

So You Think You Know Astronomy

The following questions were chosen because they represent serious misconceptions many people have about astronomy. The test itself is short. The detailed answers are a little longer.

1. Which is the first quarter moon?   ___

a                     b               c


2. A light year is ______

a. a long time

b. a long distance

c. how bright a star is over a year


3. The moon goes around the Earth   ___

a. Never, the earth goes around the moon

b. once every 28 hours

c. once  every 28 days


4. Which statement is false? ___

a. There is no gravity on the moon

b. Moon phases are caused by the Earth’s shadow

c. The moons light is caused by volcanic activity

d. All of the above are false

e. All of the above are true


5. A light second is approximately   ___

a. halfway to the moon

b. when Mars is closes to the Earth

c. a science fiction myth with no basis in reality

d. 1/ 360,000of a day on Mars

 

6.. The Earth orbits the Sun ____

a. once a year

b. twice a light year

c. when it needs to

d. never, because the Sun orbits the Earth once a day


7. The North Star ____

a. is the brightest in the sky

b. is also known as Sirius

c. is behind the moon once a month

d. none of the above

 

8.Mars has ___

a. canals made of limestone

b. been visited by robots many times

c. has moons a lot like ours

d. none of the above


9. Which is true?____

a. Venus is so uninhabitable to humans, that we might land on a moon of Saturn before anyone walks on Venus.

b. So far, nothing with mass has surpassed the speed of light.

c. So far, nothing with mass can travel at  the speed of light.

d. All above are true.

e. All above are false.


True or false section.

10.    When its summer in Utah, the Earth is closer to the sun.   ___

11.    Officially, a full moon last almost three days.   ___

12.    Rocks from Mars are now on Earth.   ___

13.    The surface of Jupiter is covered with large rocks.    ___

14.     The easiest time to see the Constellation Orion in the northern hemisphere  is in the winter   .___






Answers:

1 (A) Don’t feel too bad, everyone misses this one except Astronomers and people who look at a calendar very closely. Go look at one and you'll see.

The four  quarter phases of the Moon are as follows:


1 New Moon. The moon appears dark and is seen in the daylight sky. In fact, you might not even notice it unless its pointed out to you. The moon is now on the same side of the Earth as the Sun.  If everything lines up just right, you get a Solar Eclipse.

 

 

2 First Quarter.  I know, to you it looks like a half, but it is the first quarter of its four major phases. The moon has completed one forth of its journey around the Earth. She is way out in space with the Sun shining on what would call her Eastern Hemisphere.

 


3. Full Moon. The moon is on the far side of the Earth from the Sun. So it gets the most light. Did you ever notice that on the night of the full moon, she rises at sundown? She also goes down at sunrise the next morning. That's because of that far side business.


4. Third Quarter. Also known as Last Quarter. The moon is starting  three forth of its journey around the Earth. She is way out in space with the Sun shining on what we would call her Western Hemisphere.


And then it starts all over again with the New moon.

For extra credit:

A Moon cycle lasts for approximately 29½ days.
The phases of the Moon are the same no matter what your location on Earth, as they are determined by the relative positions of the Earth, Sun, and Moon.
The Moon rises at approximately sunset when it's a Full Moon, and approximately sunrise when it's a New Moon

When referring to the Moons age a New Moon is the starting point.
Due to the Moons cycle being 29½ days, you occasionally get two Full Moons in one month, this happens on average every 2.7 years. When this happens the second Moon of the month is called a 'Blue Moon'. When two New Moons occur in a month the second is called a 'Dark Moon'.

2 (B) A long distance. It is the distance light travels in a year. About 5,878,625,373,183.608 miles. You can see, its easier to say the Andromeda Galaxy is about 2.5 million light-years away than 5,878,625,373,183.608 miles  times 250,000,000. Or.... well you do the math.

3 (C ) Once every 28 days,  It only SEEMS to go around the Earth faster because the Earth is spinning under it.

4 (F) All these statements are false. I hear the first one (a)  all the time from people who seem to be mistaking atmosphere for gravity. A lot of people misunderstand phases too (b) . As for c, the moon has no light of its own. Most of what you see is from the sun, but there is a thing called “earthshine” where light from the sun bounces off the earth and is seen on the surface of the moon. Earthshine is most readily observable shortly before and after a New Moon, during the waxing or waning crescent phase. When the Moon is new as viewed from here on Earth, the Earth is nearly fully lit up as viewed from the Moon. Sunlight  is reflected from the Earth to the night side of the Moon. The night side appears to glow faintly and the entire orb of the Moon is dimly visible.

5 (A)  A light-second is a unit of length It is defined as the distance that light travels in free space in one second, and is equal to exactly 299 792 458 metres. It is just over 186,000 miles a second. This one was a little tricky but it could be figured out.

6 (A) The only answer. If you answered anything else especially (d) never ever get yourself booked on the TV show “Are You Smarter Than a 5th Grader.” You ain't.

7 (D) None of the above.  While its true that it is very important to us, importance does not equal brightness. (think of some some people you know). There are about 50 stars on any given night brighter than the North Star. It just never seems to move from its place in the sky and that makes it useful for navigation. It is also known as Polaris..And if you’ve ever seen the moon in the northern half of the sky, you are drinking too much.

8 (B) Robots. There are two there right now. Spirit and Opportunity.  And they weren't the first. As for a: mars has no canals. They were an illusion seen by people like Percival Lowel over a hundred years ago. Not everyone saw them even then. While its true that Mars has two moons, the word moon is used very loosely. Phobos (Greek for fear) and Deimos (Greek for dread) ain't even spherical. Deimos looks like a potato and Phobos isn’t much better.

9 (A) All are true. Because of its own greenhouse effect, Venus is way to hot , plus the atmospheric pressure is tremendous. Everything that has landed there has been crushed . As for the rest, repeat this “Nothing with mass can move faster than the speed of light”. You know are half way to understanding what Einstein was talking about.  And to obtain the speed of light, or even approach it would require more energy than you could get in this galaxy alone.

So how does light do it? The answer is in the two words, with mass. Photons, the particals of light as we understand them, have no mass. Neither do electrons. That's why electricity moves at the speed of light. Yes, they have no mass, but it doesn't seem to bother them because theyre not Catholic.        Sorry. Couldn't’ help it.


10 False.  Think about what season it is right now. Lets say its winter in Chicago. A quick check sows us that its summer in Sydney Australia. In  fact, the Sun is closes to earth in January. If you don’t understand how this works, well here. This is how Wikipedia explains it.

The seasons result from the Earth's axis being tilted to its orbital plane; it deviates by an angle of approximately 23.5 degrees. Thus, at any given time during summer or winter, one part of the planet is more directly exposed to the rays of the Sun.. This exposure alternates as the Earth revolves in its orbit. Therefore, at any given time, regardless of season, the northern and southern hemispheres experience opposite seasons.

The effect of axis tilt is observable from the change in day length, and altitude of the Sun at noon (the culmination of the Sun), during a year.

Seasonal weather differences between hemispheres are further caused by the elliptical orbit of Earth. Earth reaches perihelion (the point in its orbit closest to the Sun) in January, and it reaches aphelion (farthest point from the Sun) in July. Even though the effect this has on Earth's seasons is minor, it does noticeably soften the northern hemisphere's winters and summers. In the southern hemisphere, the opposite effect is observed.

Seasonal weather fluctuations (changes) also depend on factors such as proximity to oceans or other large bodies of water, currents in those oceans, El Niño/ENSO and other oceanic cycles, and prevailing winds.

If you still don’t get it, ask a fifth grader.

 11 False. The operative word here is officially. The real answer is an average of about three minutes. I know, I know, it looks pretty full for at least three days. But the time that the Earth side  is completely covered from side to side  is remarkably short. This is why almanacs usually give the time of a full moon to the second. In truth, where you are, say Utah, the moon may reach fullness before it rises at your horizon.

People still say “the moon is full tonight”, but then people still say” I saw the Sun come up this morning.”  What you saw was the horizon move down.

Don’t worry too much about this one.

12 True. And they have been here a long time. And they came without the help of a space program. Most scientists agree that the meteorite ALH84001 is the oldest meteorite ever found to have come from Mars.

The general consensus now is that the original rock formed 4 billion years ago on Mars. It was eventually catapulted into space by an impact and wandered the solar system for millions of years before landing on Earth 13,000 years ago.

Over 50 other meteorites have been identified as coming from Mars, but ALH84001 is by far the oldest, with the next in age being just 1.3 billion years old.

ALH84001 may have fossilized microbes in it, which would be proof some kind of life in the past. But despite what you know from the movies, scientist don’t like to jump to conclusions. More proof is needed before anybody is going to celebrate.

13 False. Jupiter as well as her nearest neighbors (Saturn , Uranus and Neptune) are called Gas Giants. They don't have a surface, not in the conventional sense. When you see pictures of these beauties, you are looking at sort of a cloud layer. If you were dive in to it, you would pass through layer upon layer of gases getting denser as you go down. Eventually your surroundings would seem more liquid, but you still wouldn’t  hit a surface of liquid. The gases would just become so dense that liquid is all you could call them. As you went farther down, the liquid becomes even  more dense, like soup, then like jelly. Next comes mashed potatoes. Then think ice cream. Are you getting the picture? Good, I’m getting hungry

14 True. In the winter it is the easiest constellation to find. Just look south and about half way up, and there it is. Depending on the time of night, as later in the night you might have to look in the south west.

Now, line the three stars in the belt up and draw an imaginary line down to the first bright star you see. That would be Sirius, the Dog Star. The brightest star in the sky. It is only 8.1 light years away. Next door almost .
Don’t think so. Look up at Orion again. Look for a bright red star above the belt. That would be Betelgeuse. Its 640 light years away. Or  5,878,625,373,183.608 time 640. I’m not even gonna try.
And in the grand scheme that's not really all that far away .

So, how did you do? Don’t worry, it was a tricky test.


Sunday
Jan302011

Obscure Joke of the Week

I ran across this old bread advert while I was looking for something else. Although the campaign was (cough, cough) years ago when I was a kid, I still remember it well.

 

But even then, I was sure the joke was lost on most of my North Carolina neighbors.

 

I was so happy, I thought I was going to plotz.Today, I live in Utah, and I can just hear some of my Mormon neighbors telling me, "But he IS Jewish."

Sunday
Jan302011

I'm Just Testing this App.

Like I said, I'm testing this app that lets me post from a mobile device.

Let's see if it can post my favorite picture of Saturn.





- Posted using BlogPress from my iPad