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ashok_bitsboymech
2005-Jan-29, 05:35 PM
hai iam ashok here.a person who likes and leaves for the space science.
i hv one fuuny but a sunny doubt.
why the sun looks for us as a sphere or rounded shape?
there reaction taking place .if any reaction taling place it should burst out and it should appear as a iiregular shape 4 us why can't it be?
similarly why stars looks like a star shaped structure,everyone saying tht star too is like a sun.then why sun looks like a round ball and this star as a star shaped.
again why can't all the planets be in square shape.why no heavernly boidies are not in a square shape.
plz whoeever seein this don't think it as silly.it has something tht makes u to think plz mail me abt this soon.
bye guyz
ashok kumar

antoniseb
2005-Jan-29, 06:04 PM
Originally posted by ashok_bitsboymech@Jan 29 2005, 05:35 PM
why can't all the planets be in square shape.why no heavernly boidies are not in a square shape.
Smaller objects can be square shaped, or any other shape. The asteroid Eros looks like a ballet slipper. However, when an object gets big enough it's gravity becomes stronger than the bonds that hold it's molecules together, and the object conforms to a round shape. Somewhere around five hundred to a thousand kilometers in diameter seems to be the critical size [depending on density, and structural strength of the material].

Concerning the Sun, gravity keeps it round. There are about six hundred thousand kilometers of gas pressing in on the reaction area, keeping the sun from getting deformed by the reaction's variation in intensity. It is also the case the the reaction intensity probably doesn't vary much over time, and so the core of the Sun is at pretty close to a short term equilibrium.

ashok_bitsboymech
2005-Jan-31, 05:43 PM
thanx mr.antoniseb.
why stars are looking like star shaped.when the objects become big it will deform to round shape ok then why some irregular galxies are there.how this universe formed?

astromark
2005-Feb-01, 02:21 AM
:huh: Ashock., you are asking some good questions. The answers you seek are complex. Understanding the structure and size of things we see in our sky is not a simple task. Many profesional Astronomers have serched , and studied the night sky for decades. No, make that hundreds of years.
As Anton has said some smaller objects may be iregular shapes. All stars are round. None of them are actually star shaped. The star shaped image you see is the light being distorted by the earths atmosphear. Our eyes are not the best viewing tools, and often distort the image. Other than our sun, which is only a mear 150 million kilomiters from us. All the stars you can see are in the galaxy we call the Milkyway. The next closest star to us is Alpha Centari. Its the brighter of the pointers near the southern cross. Its 4.33 years away from us.
and befor you ask... Sol. Our sun is just 8.4 minutes away at the light speed. Which is the distance light travels in one year. If all of this is confussing you, dont be serprised. you would not be alone. The distances between stars is usually quiet big. So we dont use kilometers. Within this Solar system we often use solar units.
that is, 1 au is the distance to the sun. You might say that Satern is 7 au from us at the moment as it goes around the sun. When we talk of other stars the distances get to great for au to be used. so we adopted the light year as a measure of distance. Sirious is about 7 ly from us. and for goodness sake dont quot any of the numbers I have used as absolutly corect. The explanation is all I am attempting to convay. All of the other stars you can see, even with a good telescop are just points of light. They are all to far away to resolve any detail of them. With the aid of telescops we can see double stars and star clusters and even other Galaxies. Be encoraged, keep asking questions.

Ola D.
2005-Feb-02, 12:20 AM
why stars are looking like star shaped.when the objects become big it will deform to round shape

Like astromark said, that's because they are very far aways. We see them twinkling because of dust particles that scatter light rays.


then why some irregular galxies are there

Mainly, galaxies come in three shapes; elliptical, spiral and irregular. Spiral galaxies contain middle-aged stars with clouds of gas and dust. Elliptical galaxies contain older stars and little gas and dust. As for the irregulars, they have an undefined shape and have lots of young stars, dust and gas.

The formation of galaxies is still one of the active research areas in Astrophysics. A generally accepted dialogue is that the structures found today were consequently formed as a result of the growing of the primordial fluctuations because of gravitational instability. It's suggested that the first galaxies were formed early as 600 million years after the Big Bang.

Guest
2005-Feb-02, 08:04 AM
hai,
again thanx for mr.astromark and ola d.i hv one other querywhy moon is appearing white to us.as it is getting light frm the sun it should also show the red or orange color.why not?also why some of the stars are forming constellations and some are not?

ashok_bitsboymech
2005-Feb-02, 08:08 AM
hai,
again thanx for mr.astromark and ola d.i hv one other querywhy moon is appearing white to us.as it is getting light frm the sun it should also show the red or orange color.why not?also why some of the stars are forming constellations and some are not?
ashok kumar

suntrack2
2005-Feb-02, 12:42 PM
Ashok are you a student of mechanical branch of birla institute of tech?
you are asking nice questions here, just increase the frequency of your question, the people in UT forum are very much intelligent in area wise and topic wise discussions hence take a full advantage and also expand your thirst of asking questions on a large scale so that the help will receive to cover the uncovered.

interesting questions by you, thanks

sunil

astromark
2005-Feb-03, 12:42 AM
large clouds of intersteller gas sometimes begine to form clumps of more dence material. If one of these areas is thumped by a large emision from a supernova or other event. It could couse the formation of new stars from within the dence cloudes of gasess. Which will now be visable to us becouse of the new stars emisions. Thus is a nebular or cluster visable to us. When you ask , constilations is this what you ment or just the random possitioning of stars from our point of view can some times appear to be in the shap of some thing else? like Scorpio. If the later is the case then remember that all though stars may look close together, they may be closer or ferther away by millions of light years.
The Moons apparent colour is just the light reflecting of its serface. Visating desert areas around the world you would note the colour of the ground is not all ways the same. For astronomicle observing we use filters to reduce the brightness of the moon. Some can even increas the detail visable.

ashok_bitsboymech
2005-Feb-05, 08:41 AM
hai
very much thanx to mr.sunil and mr.astromark.iam being glad as though i was doing my mech and my aim is to join in nasa.at this time this type of encouragements make me to thin a lot and i'll continue my queries.also suggest some good ways to join nasa.as u r my frinds senior to me i'll follow ur golden words tht will help me to enrich much more knwledge.once thanx for u all
ashok kumar
1st yr mech.bits-pilani
india
ashok kumar

rahuldandekar
2005-Feb-05, 10:06 AM
Hi Ashok,

Remember that the stars in a constellation are not in any way related to each other. They may be hundreds of light years apart. We see constellations because humans can recognise some shapes in the sky. But that has nothing to do with the stars themselves. Constellations are a human invention.