Astronomy 101

reply to post by weedwhacker


Thanks and you are correct about the observation techniques.I agree with you on the configurations as well.NASA is launching a new space telescope soon that will be able to detect Earth sized planets(we hope) and many scientist estimate that we will discover a planet capable of supporting life before 2025.

Terrestrial Planet Finder is a device to find Earth-like planets. We are looking for planets that are nearly twins of Earth, but some differences are expected because of the planet's size, environment, and history.
We will recognize such a planet by its spectrum as shown here:



An Earth-like planet is a rocky planet. Such planets will be found quite close to their star, where the temperatures are too high for the planet to be mainly made of ice. We will recognize the amount of heat on a planet by its distance from its star, and we will confirm the temperatures by the broad overall shape of its spectrum. Cool planets will be brighter at the long wavelength end of their spectrum; hot planets will be brighter at the short wavelength end.

A small object like the Moon has too little gravity to hold an atmosphere. However, an object this small could be detected in a nearby system because it would be only 12 times fainter than Earth. It could be recognized because it would show no atmospheric absorption features in its spectrum.

tpf.jpl.nasa.gov

reply to post by RobertPaulsim


"Celestia" is good, but Google Sky is even better It's Google Earth... only with the camera aimed in the other direction

I have a bachelor's degree in Physics and part of a Master's degree. I really like what you've done here for everyone. Even for people who are familiar with the material, the idea of a refresher, from time to time, is fantastic!

I tend to agree with newer theories like electric universe theory,
these informations you are providing are outdated and based on questionable
suppositions, suppression of facts (like compact galaxies connected with quasars with huge redshift difference) and bad mathematics with infinity...

and not to mention bad, close-minded, egoistic behavior of mainstream scientists towards
new ideas (that would ruin their fantasy cosmology and their life long misconceptions)

no star and no flag for you

mostly theories,
no certainties

Here is some more in depth information on stars..............

Types of Stars

Main Sequence Stars - The main sequence is the point in a star's evolution during which it maintains a stable nuclear reaction. It is this stage during which a star will spend most of its life. Our Sun is a main sequence star. A main sequence star will experience only small fluctuations in luminosity and temperature. The amount of time a star spends in this phase depends on its mass. Large, massive stars will have a short main sequence stage while less massive stars will remain in main sequence much longer. Very massive stars will exhaust their fuel in only a few hundred million years. Smaller stars, like the Sun, will burn for several billion years during their main sequence stage. Very massive stars will become blue giants during their main sequence.


Red Giants - A red giant is a large star that is reddish or orange in color. It represents the late phase of development in a star's life, when its supply hydrogen has been exhausted and helium is being fused. This causes the star to collapse, raising the temperature in the core. The outer surface of the star expands and cools, giving it a reddish color. Red giants are very large, reaching sizes of over 100 times the star's original size. Very large stars will form what are called red supergiants. Betelgeuse in Orion is an example of a red supergiant star.


White Dwarfs - A white dwarf is the remnant of an average-sized star that has passed through the red giant stage of its life. After the star has used up its remaining fuel. At this point the star may expel some of its matter into space, creating a planetary nebula. What remains is the dead core of the star. Nuclear fusion no longer takes place. The core glows because of its residual heat. Eventually the core will radiate all of its heat into space and cool down to become what is known as a black dwarf. White dwarf stars are very dense. Their size is about the same as that of the Earth, but the contain as much mass as the Sun. They are extremely hot, reaching temperatures of over 100,000 degrees.


Brown Dwarfs - A brown dwarf could also be called a failed star. During the process of star formation, some protostars never reach the critical mass required to ignite the fires of nuclear fusion. If the protostar's mass is only about 1/10 that of the Sun, it will glow only briefly until its energy dies out. What remains is a brown dwarf. It is a giant ball of gas that is too massive to be a planet but not massive enough to be a star. They are smaller than the Sun but several times larger than the planet Jupiter. Brown dwarfs emit no light or heat. They could account for some of the dark matter suspected to exist in the universe.


Variable Stars - A variable star is a star that changes in brightness. These fluctuations can range from seconds to years depending on the type of variable star. Stars usually change their brightness when they are young and when they are old and dying. They are classified as either intrinsic or extrinsic. Intrinsic variables change their brightness because of conditions within the stars themselves. Extrinsic variables change brightness because of some external factor, like an orbiting companion star. These are also known as eclipsing binaries.


Binary Stars - Many stars in the universe are part of a multiple star system. A binary star is a system of two stars that are gravitationally bound to each other. They orbit around a common point, called the center of mass. It is estimated that about half of all the stars in our galaxy are part of a binary system. Visual binaries can be seen as two separate stars through a telescope. Spectroscopic binaries appear as one star and can only be detected by studying the Doppler shifts on the star's spectrum. Eclipsing binaries are binary systems where one star blocks the light from another as it orbits its companion.

It should also be noted that a white dwarf will become a black dwarf(also called a black cinder)which is the cool core of the star.


seasky.org






[edit on 4/11/2009 by jkrog08]

Not to rain on your parade. But look up the astrological advancements in china during the Sung era. And also look at astronomy during the mighty reign of the Ottoman empire.

When one idea hit gold, it spread quickly..well as quick as merchants could travel over land and sea, hehe. But great post though.

[edit on 11-4-2009 by cenpuppie]

reply to post by cenpuppie


Thanks,the history part was a very brief summary.I just stated those particular Empires because they cover the era when it originated,I know there were many more.

Your effort is admirable, but unless people get a telescope and go out at night and start to recognize what's in the sky. It's kind of useless book knowledge unless they try to apply what you're trying to teach.

reply to post by TheInfamousOne


But it is knowledge none the less.At the least it will help them understand the environment of which they speak better and serve as a refresher to others.

Originally posted by TheInfamousOne
Your effort is admirable, but unless people get a telescope and go out at night and start to recognize what's in the sky. It's kind of useless book knowledge unless they try to apply what you're trying to teach.

I tend to disagree.

My opinion is, there are many people in society with gifted intellect, in every level of society in the developed, developing and undeveloped world.

People in the mainly undeveloped world such as Shaman have their equivalents in developed society, people are born with some quite remarkable potentials which are sometimes barely realised to as much extents they could achieve.

The more enlightened people are to what is in our galaxy and the greater cosmos, linear universe, through graphical representations either as CGI courtesy of the History Channel documentaries such as The Universe, already mentioned, which covers such a broad spectrum of cosmology, astrophysics, astrobiology, atomic and sub atomic physics, the lot.

Gifted people in all walks of society now have greater understanding in context with which to expand their intellects with, from that they are enabled to vision the solar system, galaxy and the machinations of such from the nano scopic and quantum to the macroscopic all the way to the largest most powerful phenomena in the linear universe.

People can look through telescopes all they like, it's putting that into context and perspective which expands intellect and enlightened understanding.

With the abundance of pictorial cosmic phenomena and the indescribably excellent work in the material of "The Universe" (Presentation is great as well! **Wink**) etc, so many people now have potential to expand on the machinations of the cosmos like never before in our history.

Our younger generations will mature to greater intellectual perception of the universe and i feel this will carry our race into even greater levels of advancement as we advance to our future.

As i said on IMDB a couple of years ago regards the documentary "95 Worlds and counting" which was one of the first to do as the History channels The Universe is doing.
www.imdb.com...
www.imdb.com...

Now is not called the dawning of Aquarius for nothing.

That may sound a tad exuberant, but i really do think the manner CGI has improved so much and applied to putting astrological data, telemetry etc, into context with the splendid computer representations of cosmic phenomenon is wonderful.

This puts an astral knowledge which far too long has been out of range of the public collective consciousness into the open, where once it was only the realm of the intelligentsia of universities and academies and that knowledge which has triggered gifted knowledge in our most eminent scientists in our history will now become more common place, in my opinion.

A small fraction of such knowledge we know today was responsible for sparks during the Renascence, the expansion of knowledge in the masses will help build flames of advancement which are building today to further enlighten our species through incredible breakthroughs.

The more the young and old alike are aware of the greater cosmos and it's working the better as far as i'm concerned bruv, the minds eye is a powerful tool when it can see clearly!

This material facilitates clear sight.

BTW, the uploader JimBobJoeBoo has got all of The Universe epidoses as well as a lot more material you guys will love, on the Bit Torrent tracker, The Pirate Bay.

Just bring up the site and enter JimBobJoeBoo into the search bar and it'll bring up his history of uploads, or search for - [HST] The Universe - for specific list.

I recommend using the BT client Azureus aka Vuse if using a mainframe with plenty of processor clock and RAM, lower spec 'puters may be better with Utorrent.

Paxus.







[edit on 12-4-2009 by DeltaPan]

reply to post by jkrog08


I could be going off on a tangent, but jkrog08 do you find it kinda "coincidental" that our moon rotates on its axis at the same pace as our planet so that only 1 side is visible?

Good summary of info, but one error jumped out.

*Supermassive Black Hole-A very large black hole that is at least 5 solar masses in mass.

That should be 10^5, or 100,000 as a minimum size.

reply to post by TLomon


Thanks for pointing that out,but I think I said the same thing,I just didn't multiply the exponent.

A supermassive black hole is a black hole with a mass of an order of magnitude between 10^5 and 10^10 solar masses.

wikipedia.org/supermassive_black_hole

To clear up confusion on solar mass............

The solar mass is a standard way to express mass in astronomy, used to describe the masses of other stars and galaxies. It is equal to the mass of the Sun, about two nonillion kilograms or about 332,950 times the mass of the Earth, or 1,048 times the mass of Jupiter. Its conventional symbol and value are:
See link for formulas,as this is a basic intro thread.

The solar mass can be determined from the length of the year, the distance of the Earth to the Sun (the astronomical unit) (AU), and the gravitational constant (G) as
See above
.
Until recently[when?], neither the AU nor the gravitational constant was precisely known. However, a determination of the relative mass of another planet in the Solar System or of a binary star in units of solar masses does not depend on these poorly known constants. So it was useful to express these masses in units of solar masses (see Gaussian gravitational constant).

wikipedia.org/Solar_mass

I disagree with your statement that you did it correctly. Your definition specifically states 5 solar masses (5), when it should be 10^5 (100,000). That is a huge order of magnitude difference, and as such, I still hold to my original point. It is an error that should be corrected.

reply to post by TLomon


Oh,okay sorry I didn't realize I did that.It is to late now to edit it but I will make a post about it here............

AttentionThere is an error in my OP in the definition of a supermassive blackhole.It should have been stated 10^5 or greater solar masses!

Sorry for the mistake~JKrog

Good thread apart from one thing that lets it down you mentioned Nibiru ahhhh ITS NOT REAL apart from that great.
For anyone that interested in this subject download the software on this link. Haven't looked at all the post dont know if anyone else may have mentioned it.

www.shatters.net...

Your own digital planetarium.

I like your comment about people not knowing the names of the planets and their order but it has also been stated that most Americans struggle to identify their own state on a map or other countries on Earth so I think the planets would be a problem

reply to post by wmd_2008


Ha,thanx!

I mentioned Nibiru(I am 90% sure it doesn't exist,but you know me)only as an example of threads containing information that would require some knowledge of astronomy,which for the most part doesn't.I am glad you like it~JKrog

reply to post by jkrog08


I think I understand the Niburu reference.

Any logical person who has a smattering of basic Astronomy knowledge and a basic understanding of celestial mechanics can immediately see the flaw in the 'Nibiru' concept.

To imagine a celestial body, a 'rogue' if you will, that orbits in a 3,600 year period that is supposedly going to wreak havoc on the Earth in just over 3 years' time....well, planets, even imaginary ones, don't move so fast! This notion of the 'killer' Niburu somehow 'creeping' up on us is ridiculous...and by mentioning it, you, JK, have helped to dispel the myth surrounding this fantasy!

AND, it definately belongs in this thread!!