Thoughts 20

Thoughts 20

If you want to enlarge the pictures so that the names can be read, hold down the Ctl key and tap the plus + key.

We have the standards that have been set up to represent distances in the universe from the last post. Let's take a trip to other places besides Earth.

First let's go to the Sun from Earth. It is approximately 93,000,000 miles (one AU, Astronomical Unit) from us. If we could travel at the speed of light (nothing can go faster in the universe as we understand it today) it would take 8 seconds to reach our destination. Of course we cannot come close to reaching even a large fraction of the speed of light which is 186,000 miles per second.

If we were to travel to Pluto which is 366,600,000,000 miles (39.5AU) from the sun, it would take us approximately 228 days at the velocity of light if Earth was as close to Pluto as we get.

Taking close to two-thirds of a year to get to Pluto, it would take 4.2 years to get to the Alpha Centauri system which is made up of three stars.* They are the closest stars to us. Again we would be traveling at the speed of light. From this point in our trip distances will be in light years or parsecs.

In the above picture notice that the smallest white dot is Sirius.

The Milky Way, our galaxy, is approximately 100,000 light years in diameter and 7,000 light years thick. It is a spiral arm galaxy (some say a barred spiral arm). Our solar system is somewhere is the area of ½ to 2/3 the from the center of our galaxy, located in one of the arms. The Milky Way is made up of 1 hundred-billion to 4 hundred-billion stars.** Many of these stars have planets rotating around them.

We have made a very limited trip through the solar system and then the Milky Way galaxy. Let's move into the void between galaxies. Our galaxy is moving in relation to others within what we know as the local group. The first picture gives the galaxies that are within 500,000 light years of us. The second picture shows the entire local group. ***

If you notice, the measurement is in millions of light years for the whole local cluster. Let's go about 3.5 million light years toward the galaxy Sextans A and stop in the void to look back to where we came from.

Just as we look at our bodies as a whole because we are more than the sum of our parts as we can understand them, we have looked at the Earth as a whole by using the same type of standards so our intellect can understand. The same as we do for everything else. Now looking back, we see a mediocre star that is not special in any way, about 2/3s of the way toward the rim of the Milky Way galaxy which is one of countless billions. We can see specks orbiting. Watching closely we can see the third speck out from this star is taking the first steps to exploring other bodies close to it. Could this inconsequential little speck be a living entity? While looking back from this position I know the true meaning of the word awesome. It is joyous and fearful at the same time.

*http://www.space.com/18964-the-nearest-stars-to-earth-infographic.html

**https://en.wikipedia.org/wiki/Milky_Way

***http://en.wikipedia.org/wiki/Intergalactic_travel

Two pictures from duckduckgo

All other pictures from google

Thoughts 19

Thoughts 19

Earlier I have mentioned how because of the human intellect we have to set up standards (reference frames) to try to understand our world, society or anything. This week I want to show some comparisons; reference frames that will borrow from others. I am fat weighing 275 pounds. Comparing my size to a new born of 7 pounds, I am large. Compare my size to the size of the Earth and I am small. I seem to be getting fatter and fatter but I do not believe I will be anything but small if I am compared to the Earth.

I have found illustrations that will show and tell the sizes of the planets and the distances involved in the solar system.

How Distances are Measured in Astronomy

Dealing with the numbers involved with the distances to the stars or even with those found in the solar system can be hard going. Astronomers make their lives easier by using a number of rulers (units of distance) for the distances and although they have some strange names they can be very useful for comparing the distances to stars, other galaxies and even the planets in our solar system.

AU (astronomical units)

One AU is the distance that the average distance that the Earth orbits the Sun at. The AUis most commonly used for the distances of objects with in our solar system. Pluto, the last planet in the solar system is found at an average distance of 39.47 au from the Sun. Sedna the new body nearly as large as a planet found beyond Pluto is never nearer to the Sun than 76AU and then goes to 880AU from the Sun in its giant elliptical orbit.

Light Years

One of the most common rulers is the light year. The light year is is the distance that light travel in one year (365 1/4 days). It is most commonly used for the distances to stars and other galaxies.
The nearest star is 4.2 light years away from our sun. We are 8.3 light minutes away form the Sun. the distance to the outer most planet Pluto is about 13 light hours.
Some other interesting distances in light years:

Object	Distance in light years
Nearest Star (Proxima Centuri)	4.2
Sirius the dog star (the brightest star in the sky)	8.6
centre of the galaxy	approximately 30 000
Andromeda (one of our nearest neighbouring galaxies)	approximately 2 million
The stars of Orion. (Betelgeuse and Rigel)	1400 light years

Parsec (pc)

Astronomers started measuring distances from the amount that a star moves as the Earth goes from one side of the Sun to the other. Try moving your head and you will see that the postion of everything around you changes. One parsec is derived from the smallest angle measurement of 1/3,600th of a degree or an arc second that is the angle that a star at this distance would appear to move in 6 months as the Earth journeys around the Sun. A parsec is 3.2616 light years or 30,857,000,000,000 km.. Two parsecs is 6.5532 light years or twice the distance, it is not a measure of change in angles of the stars. Due to the massive distance in the universe astronomers often use multiples of parsec commonly found are kiloparsec (kpc) a 1000 parsecs or a megaparsec (Mpc) 1,000,000 parsecs.

Below is a conversion table for some useful astronomical distance units

	kilometres (km)	Astronomical units (AU)	Light Years (l.y.)	Parsec (pc)
kilometres (km)	1	149.6 million	9,460,000,000,000	30,857,000,000,000
Astronomical units (AU)	0.0000000067	1	63,240	206,263
Light Years (l.y.)	0.00000000000011	0.000016	1	3.2616
Parsec (pc)	0.000000000000033	0.0000048	0.3066	1

*

Planet Radius Radius Object ideal ideal

(Jupiter=1) circumference diameter

Jupiter 68,700 km     1.000    basketball      73.5 cm    23.4 cm

Saturn 57,550 km     0.838    soccer ball     61.5 cm    19.6 cm

Uranus 25,050 km   0.365    softball           26.8 cm    8.52 cm

Neptune 24,700 km  0.360    softball          26.4 cm    8.40 cm

Earth 6,378 km       0.093    large marble  6.81 cm    2.17 cm

Moon 1,738 km      0.025    tiny bead       1.86 cm    5.91 mm

Venus 6,050 km     0.088    large marble  6.47 cm    2.06 cm

Mars 3,394 km      0.049    small marble  3.61 cm   1.15 cm

Mercury 2,440 km 0.036    small bead    2.60 cm    8.30 mm

Pluto 1,700 km     0.025    tiny bead      1.81 cm    5.78 mm

Charon 750 km    0.011    tiny bead      0.80 cm    2.55 mm

The chart is arranged in order of decreasing size, with the only exception being the moon given right after the Earth. **

The reason for all the data is preparing for the next post. I hope you weren't too bored this time.

Pictures are from google and duckduckgo

* http://www.telescope.org/nuffield_21_sci/astrounits.htm

** https://sciencebus.wikispaces.com/file/view/sizesofplanets.pdf/373199040/sizesofplanets.pdf

Thoughts 18

Thoughts 18

Last Friday was a national holiday and Saturday was one of my great-granddaughters' birthdays. I was out of state or traveling when I normally would have been writing. My apologies for being a day late with the post.

Hopefully, I have set up standards in the last post that show how the Earth can have accidents like humans. Still looking at the Earth as a single unit like a human, this week I will see if the Earth can have a disease like humans.

I know that the Mississippi River alluvial plain has been stripped of its' tree so that men can farm the land to make money. With the farming we have been able to better keep the human population increasing. With a continuing increase of numbers and expansion of people, economies grow. Growing economies helps, not universally, evenly or completely, to sate our natural instinct of survival. Having children helps us fulfill another natural instinct; that of reproduction, the passing of our genes. The more people there are the easier it is to indulge our need for fellowship with others, which I understand is a third natural instinct. ( since writing this I have come to see where gregariousness is a by product of survival ) So by changing the Earths surface, we can have more people, more material wealth, more gregarious and antagonistic interaction.

What are the results of one organ of the Earth doing what genetically it is programmed to do? I live in the United States of America so my knowledge is mainly from this area of the world. Hundreds of thousands of square miles of land have had trees removed clearing the land for farming in the Mississippi River alluvial plain. It is my understanding that the same process is taking place in other parts of the world. Haiti has been cleared of trees. Areas of South America are being cleared for farming like the Mississippi alluvial plain, but the ecology in South America is different. When agribusiness changed their crops to take advantage of government subsidies for produce to manufacture ethanol, there was more clear cutting of trees in the tropical far east to fill the market for the crops no longer grown by agribusiness in the USA.

Support for the growing population and affluence also demands more and more energy. Strip mining and possibly the hydraulic fracturing are making dramatic changes in the Earth. There probably are many more examples that could be used but I am not familiar with others.

Earth's population is growing at an enormous rate. Notice on the chart from 1800 through 2010.

Estimated world and regional populations at various dates (in millions)

Year	World	Africa	Asia	Europe	Latin America	Northern America	Oceania
70,000 BC	< 0.015
10,000 BC	1
9000 BC	3
8000 BC	5
7000 BC	7
6000 BC	10
5000 BC	15
4000 BC	20
3000 BC	25
2000 BC	35
1000 BC	50
500 BC	100
AD 1	200
1000	310
1750	791	106	502	163	16	2	2
1800	978	107	635	203	24	7	2
1850	1,262	111	809	276	38	26	2
1900	1,650	133	947	408	74	82	6
1950	2,519	221	1,398	547	167	172	12.8
1955	2,756	247	1,542	575	191	187	14.3
1960	2,982	277	1,674	601	209	204	15.9
1965	3,335	314	1,899	634	250	219	17.6
1970	3,692	357	2,143	656	285	232	19.4
1975	4,068	408	2,397	675	322	243	21.5
1980	4,435	470	2,632	692	361	256	22.8
1985	4,831	542	2,887	706	401	269	24.7
1990	5,263	622	3,168	721	441	283	26.7
1995	5,674	707	3,430	727	481	299	28.9
2000	6,070	796	3,680	728	520	316	31.0
2005	6,454	888	3,917	725	558	332	32.9
2010	6,972	1,022	4,252	732	580	351	35.6

1. ^ Jump up to:a b c d e Northern America comprises the northern-most countries and territories of North America: Canada, the United States, Greenland, Bermuda, and St. Pierre and Miquelon. Latin America comprises Mexico, Central America, the Caribbean and South America. *

What I have said so far in this post is enough to show that not only can Earth have sores like humans, it can also have diseases. What is cancer:

World English Dictionary

cancer  (ˈkænsə)
— n
1.	any type of malignant growth or tumour,  caused by abnormal and uncontrolled cell division:  it mayspread through the lymphatic system or blood stream to other parts  of the body
2.	the condition resulting from this
3.	an evil influence that spreads dangerously

Are humans a cancer on this Earth? Could we be making this whole world uninhabitable; one big sore.

*World population chart from:

http://en.wikipedia.org/wiki/World_population


All photographs in this post are from google.