Common misconceptions about astronomy

[karakoram]

Very informative thread. Thumbs up to @500

 

[rishav]

Apparently water existed on Earth since its formation

i dont think this is true , because at the beginning earth was a really really hot place with lave flowing all over the place , and it was constantly being hit by meteorites and other rocks from space . so how can water exist in such situation ?

i have heard that nutrinos are very difficult to intercept ,they can pass through 1000s of kms of iron sheet

 

[Anubis]

24) Big Bang is a fact.

We know for sure that universe is expanding and that 13.7 billion years ago it was very hot and dense. But still it does not prove a Bing Bang. Big Bang theory does not work without inflation theory and in order to prove inflation we need to register gravity waves from it. Best way is to detect polarization of CMB by gravity waves. So far it was not detected thus Big Bang remains a theory.

25) Known universe started from the Big Bang.

According to current model, first was a "cold" Inflation stage expansion and only after that inflation field energy transformed into matter and heat, making it super dense and super hot, creating a Big Bang.

This misconception we can see in popular shows for example "How the universe works":

How the Universe Works S03E04 First Second HDTV XviD-AFG - Vidto (what they say from 10:46 is WRONG)

Bad choice of words..theories are facts...hypothesis are not facts.

 

[rishav]

right now we dont have any better way to explain the beginning of universe than the big bang . the oldest light that we can see in space , we assume that is where big bang occured. beyond which we cannot see . btw we also cannot see beyond a black hole . so it be possible that we are the other side of a black hole that is doing what every blackhole does sucking in everything which comes within its reach , and this also explains why the universe is expanding !

 

[500]

i dont think this is true , because at the beginning earth was a really really hot place with lave flowing all over the place , and it was constantly being hit by meteorites and other rocks from space . so how can water exist in such situation ?

i have heard that nutrinos are very difficult to intercept ,they can pass through 1000s of kms of iron sheet

Meteorites are not a problem for water, they did actually bring some water with them, but small portion compare to total.

Bad choice of words..theories are facts...hypothesis are not facts.

No, theory is not a fact. Theory is well developed hypothesis.

right now we dont have any better way to explain the beginning of universe than the big bang . the oldest light that we can see in space , we assume that is where big bang occured. beyond which we cannot see .

1) There is no place where the big bang occurred, or more correctly it occurred everywhere. Imagine infinite super dense universe that started to expand and turn into less and less dense. Thats the big bang.

2) The oldest light we can see comes from 380 thousand years after the Big Bang.

 

[rishav]

^during infancy of earth ,it was violent , constantly pummeled with objects from outer space , its surface had many cracks and was too hot to have water . but after few million years it cooled and then the water must have come from some chemical reaction . i dont know exactly how it came , but surely earth didnt have water from the beginning.

There is no place where the big bang occurred, or more correctly it occurred everywhere

that is just a hypothesis just like the big bang , but expanding from a point(source of all the materials) seems more likely than expanding from everywhere .

 

[500]

that is just a hypothesis just like the big bang

Its not a hypothesis like the bing bang, IT IS the bing bang.

but expanding from a point(source of all the materials) seems more likely than expanding from everywhere .

No thats very wrong concept of the big bang. Universe is same in all directions. That would not happen in case of expansion from one point.


Big bang is expansion of infinite universe.

 

[kbd-raaf]

Astronomy. Truly the most useless discipline. Should not be publicly funded.

 

[rishav]

^
Today, millions of people across the world are affected by advances in astronomy.

Industry

— Your iPhone’s camera is a charge-coupled device (CCD) — an instrument, which converts the movement of electrical charge into a digital value. Originally developed for astronomy, CCD’s are now used in most cameras, webcams and cell phones.


Every iPhone with has a built-in CCD

— The computer language Forth, originally developed for the 36-foot telescope on Kitt Peak is now used by FedEx to track packages.

— AT&T uses IRAF — software written by the National Optical Astronomy Observatory — to analyze computer systems.

— Kodak film, originally created by astronomers studying the sun, is used extensively by the medical and industrial industries, photographers and artists.

Aerospace

— Space-based telescopes have advanced defense satellites, which require identical technology and hardware.

— Global Positioning System satellites rely on astronomical objects — quasars and distant galaxies — to determine accurate positions.

Energy

— Technology gained from imaging X-rays is now used to monitor fusion — where two atomic nuclei combine to form a heavier nucleus — that may prove to be our answer for clean energy.

Medicine


Magnetic resonance imaging utilizes aperture synthesis – first an astronomical technique and now a medical technique.

Astronomy struggles to see increasingly faint objects; Medicine struggles to see things obscured within the human body.

— Aperture synthesis — the process of combining data from multiple telescopes to produce a single image seemingly created from a telescope the size of the entire collection — first developed by a radio astronomer has been used for multiple medical imaging tools, including CAT scanners and MRIs.

— Building space-based telescopes requires an extremely clean environment in order to avoid dust particles from obscuring the mirrors or instruments. Similar methods and instruments are now used in hospitals and pharmaceutical labs.

International Collaboration

— Collaboration also inspires competition. The Space Race — a competition between the Soviet Union and the United States for supremacy in space exploration — landed Neil Armstrong, Michael Collins and Buzz Aldrin on the moon.

— Astronomy is a collaborative effort. In 1887 astronomers from around the world pooled their telescope images in order to create the first map of the entire sky. Today, astronomers travel around the globe to attend conferences, learn from one another, and utilize telescopes elsewhere.

Everyday Life

— Airports utilize advances in technology designed for astronomy. X-ray observatory technology is used in X-ray luggage belts. A gas chromatograph — an instrument designed for a Mars mission — is used to analyze luggage for explosives.

— Stephen Hawking’s “A Brief History of Time” has sold over 10 million copies. Carl Sagan’s television series “Cosmos: A Personal Voyage” has been watched in over 60 countries.

Humankind

“Perhaps the most important reason to study astronomy is that astronomy seeks to satisfy our fundamental curiosity about the world we live in, and answer the ‘big’ questions,” Dr. Rosenberg told Universe Today. “How was the universe created? Where did we come from? Are there other intelligent life forms?”

Every advance in astronomy moves society closer to being able to answer these questions. With advanced technology — increasingly complex CCDs and larger ground- and space-based telescopes — we have peered into the distant, early universe, we have searched for habitable worlds, and we have come to the conclusion that we, ourselves, are stardust.

“Astronomy constantly reminds people of two seemingly contradictory things. First that the universe is infinite and we are of but the tiniest fraction of importance. And Second that life is rare and precious. A home as beautiful and unique as earth does not come often. We must protect it.”

An upcoming version of this paper will not only cover the tangible aspects of astronomy discussed here, but also the intangible aspects of astronomy.

The paper has been accepted has been published on the International Astronomical Union website and is available for download here.

source : http://www.universetoday.com/106302/how-astronomy-benefits-society-and-humankind/

 

[Anubis]

Meteorites are not a problem for water, they did actually bring some water with them, but small portion compare to total.


No, theory is not a fact. Theory is well developed hypothesis.


1) There is no place where the big bang occurred, or more correctly it occurred everywhere. Imagine infinite super dense universe that started to expand and turn into less and less dense. Thats the big bang.

2) The oldest light we can see comes from 380 thousand years after the Big Bang.

I thought fact means data in science...Theory is the highest form of knowledge...the heliocentric theory...germ theory of disease...theory of evolution...I have never seen anything termed as fact in science.

 

[Ultima Thule]

No thats very wrong concept of the big bang. Universe is same in all directions. That would not happen in case of expansion from one point.

Are you stating study state model? than you are wrong, study state model proves false by scientists, if we look further into the Universe, The Universe apears different from different angles

Big bang is expansion of infinite universe.

their is a controversy between scientists Cosmos is either finite or infinite

 

[500]

I thought fact means data in science...Theory is the highest form of knowledge...the heliocentric theory...germ theory of disease...theory of evolution...I have never seen anything termed as fact in science.

Many things can be called facts:

That Sun is about 150 mln kms from earth, that Sun is about 333 K times heavier than Earth, that Sun consists mainly from H and He etc etc..

As for theory, theory became solid when it is confirmed by many tests. For example relativistic theory confirmed by swarms of tests. As for big bang we still dont have a solid confirmation of inflation theory.

Are you stating study state model? than you are wrong, study state model proves false by scientists, if we look further into the Universe, The Universe apears different from different angles

No its same from all directions.

their is a controversy between scientists Cosmos is either finite or infinite

I wrote the same earlier here. But for sake of simplicity u can consider it a infinite. We dont see any border effects so technically its infinite.

 

[Ultima Thule]

Many things can be called facts:

That Sun is about 150 mln kms from earth, that Sun is about 333 K times heavier than Earth, that Sun consists mainly from H and He etc etc..

As for theory, theory became solid when it is confirmed by many tests. For example relativistic theory confirmed by swarms of tests. As for big bang we still dont have a solid confirmation of inflation theory.


No its same from all directions.


I wrote the same earlier here. But for sake of simplicity u can consider it a infinite. We dont see any border effects so technically its infinite.

No Sir Universe isn't same in all directions its a. Universal fact that most scientists believe

No one knows that Cosmos is finite or infinite that includes you

 

[livingdead]

I thought fact means data in science...Theory is the highest form of knowledge...the heliocentric theory...germ theory of disease...theory of evolution...I have never seen anything termed as fact in science.

fact is a misleading term... theory is an widely accepted model that confirms to past and current observations about the universe and might even make predictions that upon observation seem to match...
hypotheis is a proposition of such a model, before its accepted(if it matches all the observations upon testing)....
so every theory started its life as a hypothesis.. then accepted as theory... then rejected or tweaked when new data does not fit.