EldwinSchrodinger @ we're not safe on Earth!
apart from global warming and other disasters that might hinder the human survival on earth. i'll also need to include that we're also prone to external threats. i'm not referring to "alien domination" but more of a nearby sun. i would like to encourage humans to go up to space and learn to adapt to it. i'm not sure how long we're able to leave. its better we start to know our heavens first before its too late.
we're surrounded by many supergiants within our galaxies and in any instance, one could just result in a stellar explosions. that we cant hope as thats how stars end their life. harmful gamma rays will damage our ozone and harm us just like the effects of the nuclear explosion in Hiroshima.
what we can hope is when a star were to collapse. neither its cores are facing us directly. as i've mention earlier. (the lines in white) which are called gamma ray burst. mainly ejected from the inner cores of the collapsing star has its highest intensity of gamma rays. they're are triggered when the core of a massive star collapses to form either a black hole or a neutron star. traveling at very near light speed. shock waves within the jets generate the actual gamma rays, and the star itself blows apart as a supernova of either type Ib or Ic (meaning the supernova's spectrum lacks hydrogen, presumably because the outer hydrogen-rich layers were blown off in the star's wind prior to the explosion)
Labels: Fate Of Mankind
EldwinSchrodinger @ Humans create black holes?
i've seen articles whereby scientists wanted to create "mini" black holes which are smaller than an atoms. according to some of them. these small black holes already existed during the big bang era. now that dark matter could be created in particle accelerators, its no doubt someone would try to create a blackhole. yes now the problems lies in containing it and supporting its weight. if were to have one on earth, it'll definitely slice through earth like a knife through a cake. yeah i understand blackholes are an essential energy source to power mechanisms. but how to contain it? how to keep it in place? btw, blackholes do explodes. when i say explode. its not just a ton of tnt. its a billion megaton bomb exploding. thats would cause a potential harm to earth. some of them last for billion years depending on its mass and sizes.
Labels: Blackholes
EldwinSchrodinger @ Big Bang and infinite mass
we all know, anything beyond the planck scale - an exact theory of quantum gravity, physics equations simply breakdown. now lets go back in time to the beginning of the universe. eventually one would reach a state of sufficient temperature and density that a fully quantum mechanical theory of gravitation would be required and it corresponds to incredibly small distances. unfortunately general relativity does not respect the principles of quantum mechanics. which makes it tougher to create a unified theory of everything.
i have always love to relate black holes to the big bang. because its totally opposite of each other. one spills matter out and the other sucks in matter! now lets cut the story short. i did research for almost 2 months on the big bang and now i thought to myself. what if its all wrong?
there's a limit on how much matter can be stuffed into a particular space (putting aside collapsed stars) that should also apply to the big bang model.
if there isn't time, the bang wouldn't have created =P. a few months ago, i thought to myself. what if the singularity of the big bang was actually a reversed blackhole from another universe that spilled matter out? for that i have to take parallel universe into consideration.
Labels: Big Bang
EldwinSchrodinger @ what will happen to our sun?!
now lets recap. remember some of the earlier post about exploding stars? it may not end its life soon. but one day it will. its a matter of a few billion years before our sun burnt out its nuclear fuel in its core. and of course. at that time, its theorized, gravity will at last begin willing the "tug-of-war". a ball of dense, HOT gas about 865,000 miles across begins to collapse.
when its more or less condensed or not so hot i should say, it'll become a "white dwarf"
a seething ball of atomic nuclei and loose electrons that in the case of the sun, its only 4 times as large as earth, estimated in cosmic terms of course.
the mass, would still be about the same for now, however, its gravitational pull on the atomic matter at its surface would be far stronger than it is today on earth. imagine the velocity required for an object like a rocketship to escape from the sun's surface would have increased from our 380 mph to over 2,100 mph!
The sun will of course continue to collapse. its certain that it could collapse indefinitely. top get to that point. the star has to be very massive. incase of our sun, with average initial mass, it will collapse no further once it becomes a white dwarf.
in the law of physics, it states that 2 electrons cannot occupy the same energy space, means that there is a limit to how tightly matter can be packed together. this limit apparently is still applicable to white dwarfs. read on and see how this limit breaks down. lols
now, if the original star has a greater mass, lets say its 1.4 times greater than our sun, the exclusion principle (in blue fonts) will be overpowered by gravitation. such stars will collapse further, breaking atomic nuclei apart, destroying atoms.
it then eventually becomes a "neutron star" a heavy mass of neutrons just a mile across. escape velocity at the surface would be 120,000 mph!
and if the star is 3.6 times the mass of our sun, it'll not stop contracting at the neutron star stage. now gravity clearly in charge. it draws the star further down into itself. finally it reaches the point whereby the escape velocity reaches186,282 mph. and thats the speed of light. bythen the star would glow dim and not brighter than a weak electromagnetic shadow. now i believe you should know that that star is by now. a black hole!
btw a black hole is NOT black but its invisible. you'll never be able to trace a blackhole with a telescope. but you'll be able to see one if it happens to devour matter and leaves an accretion disc behind.
Labels: Stars And Suns
EldwinSchrodinger @ Mood orbital distance increasing over time.
The moon's increasing distance has to do with a physics concept called angular momentum, which is a body's resistance to a change in its rotation or orbit. if we look at the earth-moon system, we find 2 sources of angular momentum
-Earth, which rotates once every 24 hours and the moon, which orbits earth every 27.3 days.
The moon also rotates , but earth's gravitational influence has slowed the moon's rotation to the point that it always keeps the same face pointed towards us. and we call that tidal locking*. thus, the moon rotates every 27.3 days.
A fundamental physics law says that the total angular momentum of a system, in this case, earth and moon, must remain unchanged unless some outside forces messes with it.
Earth and the moon constantly exert gravitational pull on each other. earth's pull has tidally locked the moon's rotation, and the moon's pull raises tides here on earth.
the friction of the water being moved back and fourth over the ocean floors has gradually slowed earth's rotation over the eons. 900 million years ago, our day was only about 18 hours at that time. as earth's spin slows, some of its angular momentum is lost.
but nature demands angular momentum to be conserved. that means the moon must increase its angular momentum to compensate to earth's loss.
there are 2 ways to do this. speed up, which the moon can't do, or increase its distance, which it can. so, over time, the moon recedes from earth.
this will continue until earth's rotation has slowed to the point where the length of our day is the same as the time it will take the moon to orbit earth: or simply said, until earth becomes tidally locked to the moon.
the bottom line.. tidal friction, caused by the moon's gravitational influence, is slowing earth's rotation rate.
Labels: Astrophysics
EldwinSchrodinger @ Dark matter theory solved?
CRASH COURSE. This composite image from several observatories and telescopes shows where two clusters of galaxies collided 100 million years ago. The ordinary matter, shown in pink, from the two galaxies collided, whereas the dark matter from each galaxy, shown in purple, passed straight through.Markevitch, et al., Clowe, et al., Magellan, Univ. of Arizona, CXC, CfA, STScI, ESO WFI, NASA
Scientists have offered two competing explanations of this discrepancy. The first is that an invisible substance called dark matter accounts for 90 percent of the universe's mass and gravity. Although scientists don't know what dark matter consists of, they propose that it keeps each galaxy intact (SN: 8/13/05, p. 104: http://www.sciencenews.org/articles/20050813/bob9.asp).
The second explanation says that dark matter doesn't exist and that traditional models of gravity simply need modification.
To search for dark matter, Douglas Clowe of the University of Arizona in Tucson and his colleagues used several telescopes and observatories to image an unusually energetic collision between two galaxies that occurred 100 million years ago.
Normally, as galaxies travel through the universe, gravity keeps dark and ordinary matter close together, so the invisible substance can't be distinguished. During a galactic merger, however, hot gases from one galaxy bump into hot gases in the other and both galaxies are slowed by a force similar to wind resistance. But dark matter from one galaxy, in theory, passes right through another galaxy's dark matter (SN: 4/23/05, p. 264: http://www.sciencenews.org/articles/20050423/bob9.asp).
"Dark matter particles don't experience the same type of drag that slows down gas clouds," says Clowe.
His team used a technique called gravitational lensing to locate the main mass in the aftermath of the collision (SN: 5/20/00, p. 332: Available to subscribers at http://www.sciencenews.org/articles/20000520/note10.asp). If dark matter didn't exist, all the mass would have been lumped together with the gases. Instead, the researchers found most of the mass in clumps that appeared to have whizzed past the hot gases.
Only a theory of gravity that includes dark matter can explain the separation, Clowe's team argues in the Sept. 10 Astrophysical Journal Letters.
"This proves in a simple and direct way that dark matter exists," says coauthor Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "It puts to rest the remaining doubt that cosmologists have had until now."
The matter separation caused by the collision is "mind-boggling," says cosmologist Michael Turner of the University of Chicago. However, he adds that the researchers can't rule out alternative theories, in part because the models from them are so inconsistent.
Alternative models will have a hard time challenging the new finding, maintains astrophysicist Katherine Freese of the University of Michigan in Ann Arbor. "It's going to make it tough for anybody to compete," she says.
Down the line, the observation might give researchers important insights into intergalactic mergers, says Turner. "It's kind of like a cosmic centrifuge," he says.
Labels: Dark Matter
EldwinSchrodinger @ The fundamentals of the sizes of the universe.
Have you ever wondered. how big is BIG? and whats earth and our sun compared to the trillions of galaxies in the universe?
now lets imagine the sizes all starting from an electron. ;)
Electrons -----> 2.82 × 10^15 metresPhotons -----> 10^15 metres
Atom -----> 0.1 nanometres
Virus -----> 25 - 250 nanometres
Human hair -----> 56 - 181 µmetres
Mercury -----> 4880 Kilometres
Mars -----> 6794 Kilometres
Venus -----> 12104 Kilometres
Earth -----> 12756 Kilometres
Neptune -----> 49532 Kilometres
Saturn -----> 108728 Kilometres
Jupiter -----> 142984 Kilometres
Sun -----> 1392500 Kilometres
Sirius A -----> 2506500 Kilometres
Pollux -----> 6962500 KilometresArcturus -----> 33420000 Kilometres
Rigel -----> 86335000 Kilometres
Beteiguese -----> 905125000 Kilometres
Antares -----> 1108430000 Kilometres
Mu Cephei -----> 3481250000 Kilometres
W Cephei -----> 3676200000 Kilometres
W cephei is about earth's diameter times 288194!Astronomers predict that Betelgeuse will ultimately undergo a type II Supernova explosion although it is possible that the mass is low enough for Betelgeuse to leave a rare oxygen-neon white dwarf. Opinions are divided as to the likely timescale for this event. Although Betelgeuse is 
only around 10 million years old, some regard the star's current variability as suggesting that it is already in the carbon burning phase of its life cycle, and will therefore undergo a supernova explosion at some time in the next thousand years or so. Skeptics dispute this contention and regard the star as being likely to survive much longer. There is a consensus that such a supernova would be a spectacular astronomical event, but would not — being so distant — represent any significant threat to life on Earth.
Even so, Betelgeuse would brighten at least 10,000 times as a supernova, causing it to shine with the luminosity of a crescent Moon. Some sources predict a maximum apparent magnitude equal to about that of the full Moon (mv = -12.5). This would likely last for several months. It would look like a brilliant point, the brightness of a full Moon with the color of an incandescent bulb at night, and easily visible in daylight. After that period it would gradually diminish until after some months or years it would disappear from naked eye view. Then Orion's right shoulder would vanish for a time until, in a few centuries, a splendid nebula would develop. However, if Betelgeuse's axis (one of its poles) is pointed towards Earth there would be tangible effects here such as the aftermath of the GRB (gamma ray burst) from a supernova or wolf rayet star. A shower of gamma rays and other cosmic particles would be directed at Earth. There would be spectacular aurorae and possibly a measurable diminution of the Ozone layer with consequent adverse radiation effects on life. In such an orientation towards the solar system it would also appear many times brighter than if its axis were pointed away.
Betelgeuse could have turned into a red giant star. It is known that as stars use up the hydrogen fuel in their cores, their color changes from white to yellow to red. suggest that Betelgeuse could have changed its color when it expelled a shell of dust and gas, that, even now, can be seen to be expanding away from it. Thus, if their theory is right, it is unlikely that Betelgeuse will become a supernova any time soon because a star usually stays a red giant for tens of thousands of years. The approximate size of the red supergiant is 5.5 times larger than Earth's orbit itself being 822,788,285 kilometres.
Labels: Astronomy
