Q&A: ASTRONOMY!!!!!!!!!!!!!!?
Query by Juan Cruz: ASTRONOMY!!!!!!!!!!!!!!?
1) Describe the total everyday life cycle of a sun-sized star, from birth to death. A diagram may be be useful but is not needed.
two)What are the two varieties of supernova, and what causes every one particular???
three) What are “dark matter” and darkish energy,” and how do we know each one exists???
4) Clarify the method of fusion. Specially: a) what is it, b) the place in a star does it transpire, and c) as a star’s existence continues, what will materialize to the fused particles???
five) What is the Major Bang??? Make clear at minimum a few pieces of proof that are employed to assistance the principle of the Significant Bang,
Very best solution:
Answer by Bobby
All these answers are in your TEXT E-book.
Give your response to this query beneath!
Institute for Astronomy
Picture by hawaii
The 2010 University of Hawaii Institute for Astronomy Open House.
Question by Josh: What sensible worth did astronomy supply to historical civilizations? It served them uncover employs for historic stru?
What practical appeal did astronomy present to historical civilizations?
A. It helped them come across utilizes for historical structures like Stonehenge.
B. It authorized them to predict eclipses with excellent accuracy.
C. It assisted them recognize our cosmic origins.
D. It helped them preserve track of time and seasons, and it was used by some cultures for navigation.
Ideal reply:
Solution by paul h
For the most component, D athough B applies as well. Structures like Stonehenge are assumed to have been developed to cautiously observe and caculate solstices, equinoxes and other yearly activities. Other wood and stone henges have been located in a wide range of other cultures…some dating even before.
“One more ‘Stonehenge’ learned in Amazon ”
http://www.msnbc.msn.com/id/135/
“Woodhenges Previous to Pyramids”
“The historical inhabitants of Britain had been constructing significant structures in advance of Cheops, builder of the Good Pyramid, was even born! A person of these structures is 5,000 decades outdated.”
http://www.science-frontiers.com/sf115/sf115p16.htm
“Stonehenge might be far more advanced in terms of astronomical alignments, but it is dwarfed by the newly found out henge bordering Ireland’s hill of Tara. (A “henge” is only a circular ditch and embankment.) The henge’s ditch at Tara is 3 meters broad with a curious series of pits on possibly aspect. Its diameter is about 1 kilometer (5/eight mile) compared to Stonehenge’s diminutive 100 meters.”
http://www.science-frontiers.com/sfጻ/sf123p03.htm
“Neolithic engineers may perhaps have utilised ball bearings in the development of Stonehenge, it was claimed at this time.
The very same technique that enables vehicles and machinery to run easily currently could have been utilised to transport the monument’s large standing stones additional than four,000 decades in the past, in accordance to a new principle.”
http://www.independent.co.united kingdom/existence-design/history/stonehenge-mystery-could-relaxation-on-ball-bearings-2137673.html
The Best fifty megalithic stone sites in the world…..
http://www.historical-wisdom.co.uk/top50stones.htm
Historic astronomers tracked the stars and the yearly appearance or disappearance of constellations like the Pleiades in purchase to predict the optimum time for planting and harvesting which was essential to agricultural societies. And several incorporated astronomical activities or signs into their mythologies/ theologies.
The Nebra star disc…..
http://channel.nationalgeographic.com/episode/secrets-of-the-star-disc-4209/Overview
The Antikythera mechanism…an historic computer of celestial activities….
http://www.nature.com/news/2010/�/complete/468496a.html
Give your answer to this query under!
June 16th, 2011 at 4:36 am
One question at the time please. All five are big subjects!
Here is #1:
It all starts with a cloud of gas.
Due to gravity the cloud will start to shrink. This collapse is usually triggered by a shockwave from a nearby supernova or expanding planetary nebulae.
As the cloud contracts the rotation will become faster and it will brake up into individual clumps. If these masses are big enough the density and temperature in the core will become high enough so that nuclear fusion can start. Hydrogen will be converted into Helium. The “burning” of Hydrogen produces a counter pressure to gravity that will stop the gas cloud from further shrinking. The gas cloud becomes a stable star. This is the present state of our Sun.
This so called main sequence stage will last 10 billion years for the Sun. Over this time the Sun evolves very slowly as it consumes Hydrogen in its core. It grows slightly larger, gets brighter and hotter.
After billions of years, when most of the hydrogen fuel in the core has been used, fusion stops. The inert helium ash that has built up in the core starts to collapse under its own weight. This causes the core to heat up and to ignite the hydrogen in a thin shell around the core. The Sun grows slowly and becomes first a Yellow Subgiant and then a Red Giant.
In the giant stage our Sun will expand to the size of the orbit of the Earth.
Inside the collapsing core the temperature is now high enough so that the heavier elements carbon and oxygen can be made. When the Sun runs out of this type of fuel, it has neared the end of its life.
The Sun then begins to throw off layers because it can’t support anymore. This is called a planetary nebula. The core of the star becomes a white dwarf. This is an extremely dense star the size of a planet. Finally, when the white dwarf has cooled down, it stops shining and becomes a “black dwarf”, a dead star. This is expected to be the final state of our Sun.
For stars with higher masses than the Sun (up to about 40 times greater), the outer layers of the star may explode. This is a supernova. This type of star collapses down to a very compact size. Depending on the initial mass of the star, this may be a “neutron star” or a “black hole”.
http://en.wikipedia.org/wiki/Star
http://en.wikipedia.org/wiki/Hertzsprung-Russell_diagram
http://en.wikipedia.org/wiki/Supernova
http://aspire.cosmic-ray.org/labs/star_life/starlife_main.html
http://www.windows.ucar.edu/sun/Solar_interior/Nuclear_Reactions/Fusion/Fusion_in_stars/star_life.html