Astronomy and Cosmology

Hi guys I am looking for a dataset to use in my thesis. I am working on UNION 2.1 sample of supernovea Ia data. That dataset consist of redshift and distance modulus with uncertainty (sigma) for 590 supernovea. Do you guys know where can i find similiar dataset for GRBs?

I am not a physics major, just interested in the discussions about cosmology. But many times get lost in the discussions. Many people show the beautiful fit of the model and the observed CMB power spectrum (~ like the one below copied from Wikipedia). But I can not find the mathematical equation(s) of this best-fit lambda CDM model... Could anyone help??? Thanks a lot!

I am a student and we are working on a satellite project. I need help regarding the payload transmitter portion of satellite of frequency 433.9MHz and data rate 256kbps using BPSK modulation technique. If any relevant link .. kindly inform

I spent some time over a month ago seeing what model for the big bang exists. As far as I was able to get, the argument was that a quantum fluctuation generated the universe. Is that quantum fluctuation argument the current view on how the universe was generated?

With all the handwringing concerning what we should do if a large asteroid threatens Earth, I have a pretty simple idea. Embarrassingly simple. The Japanese have already demonstrated we have the technology to land a spacecraft on an asteroid, so, we land one or more relatively small spacecraft on the asteroid, rotate the landing engines 180 degrees, fire them up, and literally push the asteroid into another trajectory. Please spell my name correctly on the check, Mankind.

Dear All, As I have mentioned on another post on a different forum, I am doing some research for a science-fiction book as part of the story, and I was wondering about some details of the moon Titan. One chapter describes the crew landing on Titan and disembarking from a spacecraft onto the surface. My question is this: What would they see across the surface? I read somewhere that Titan has a denser atmosphere that Earth, and there is a layer of haze at some point. However, would this haze be seen as a sort of fog across the rock? Or would the low-level air be clear enough to see for a long distance? Please provide any explanations you can; it would be…

Hello, members of the Science Forum community. I am a 15 year old with a huge interest in Astrophysics and Astronomy as a whole. But it has been very inaccessible for me, for learning Astrophysics is no piece of cake. I'm merely another product of a typical educational system with a laughably limited amount of knowledge regarding Physics and/or Astronomy. So basically, i just want to know that before I get into reading higher level books or scouring the internet for information, what are the basics I require and the foundations I need to comprehend an average (higher level) article regarding the fields? I realize my question is rather vague, but I hope I got my point ac…

1. What would happen if the earth were to stop rotating? 2. What happens in a black hole? My theory is that nothing actually disappears but rather breaks up into millions of pieces and therefore seems like something has disappeared 3. Will it ever be possible to cut through the centre of the earth? E.g. from australia to japan

Based on the big bang theory, stellar and planetary development requires gravity to accumulate cosmic gas, but particles move too fast to coalesce. At -272.15°C, hydrogen atoms move at 158 meters/second while helium atoms move at 79 meters/second. All you need is a velocity of 4.31498e-14 meters/second to escape the gravitational pull of an H2 molecule. There’s no doubt that cosmic clouds possess a lot of gravity, but the gravity is divided by the gas particles that make up the cloud (mass = gravity). Hence, the gravitational sum doesn’t coalesce anything because it can’t get the first two gas particles to cohere. It can only move the matter to a particular direction to…

Rather than sidetrack my other post I will ask the question here. I have been unable to find any useful description of the word photon other than discrete bundle or wave-packet neither of which are very helpful. The descriptions available seem to describe a particle like structure rather than a wave like structure. So how are photons and waves connected, what relationship does the energy of a photon have with wavelength. If light travels as photons why bother to describe it moving as Electro-magnetic waves.

A few days ago I read about this globular cluster of stars coming at us 'like a cannon ball'! (reporters crack me up!) According to the article, there is a cluster of 100,000 stars heading this way from 53 million light years away. They are figuring it will be here in about 17-18 million years. Now please bare with me, I might start talking out of my butt here... but if the cannon ball is traveling at 2 million MPH(according to the article), which is 894 Km/sec, isn't space expanding faster than that with these kind of distances? Expansion increase the further apart items are, right? I get the fact Andromeda Galaxy will reach us, it is only 2.5 ly away. W…

http://www.cfa.harvard.edu/news/2014-10 http://www.illustris-project.org/ awesome development, can't wait to see the published papers and B-body codes. Looks cool on the vid

Tell me science, whats past it?

Just need to test a light cone calculator for display compatibility on this forum. the light cone calc can be found on my signature thanks for the patience the calc is not compatible, it is on some forums but not this one http://www.einsteins.../LightCone.html http://cosmocalc.wikidot.com/start

Recently while posting a theory about how the universe works on another site, I came across a problem when dealing with waves and gravity. The basis of the problem goes back to one of the ancient greeks and his thoughts on infinity. If you take a curved surface, in this case a star, and draw as many straight lines as possible radiating out from its surface then no matter how many lines you draw if you draw a larger circle around the original there will be gaps between the lines, the greater the radius of the second circle the bigger the gaps. Light travels, basically, in straight lines. EM waves oscillate, 2 waves at right angles, simulations are easy to find on the in…

Two questions here. The first is about the red shift of light and it came about in another thread called galaxy rotation curve. The answer I understood was, we can determine the rotational speed of galaxies by the red shift of their light. So I went to Google and stated to research red-shift which led me to my question: How do we know that light is red shifted because the light source is moving away from us and not from something else? ie: Gravity has been proven to affect light, couldn't the source be closer and simply shifted red? (Black holes, dark matter...etc) Second question, in researching red shift I came across many weird sites that claim they…

As far as I know, the expansion of the universe only has a correlation to distance. If something 13 billion years away is receding at 80% the speed of light, the "Big Rip" implies that the hubble volume would shrink and after a million years, something that's only 13 billion years away would then recede at 90% the speed of light instead, whereas normal space expansion would say that it doesn't matter how much time passes, something 13 billion light years away is always going to appear to be receding at 80% the speed of light. So why wouldn't the expansion have a constant acceleration in proportion to distance and simply lead to a big chill? Why does anyone think there's a…

Having nothing better to do, I was rambling over the Net* and found this page. Where I wondered about this statement under the first article Inflation on the back of an enveloppe, exponential expansion, 3rd paragraph Where it is stated that "The universe is different — it can expand without diluting its mass density". Question: does that mean that the mass density of the universe is not time dependent, IOW that today's mass density of the universe is the same than the mass density before expansion began? *following Swansont's footsteps.

I have been a big follower of the efforts of finding planets and something has been bothering me for a while. How many planets can orbit a star close together? Our inner solar system is quite barren compared to many of the stars we have found planets around. A few contain several earth sized or larger planets within what would be in our solar system the orbit of mercury. Would it be possible to have several earth sized planets around a sun like star within the orbit of Mars? If not why not?

Hi I am 13 and am wondering if anyone believes in the big bang theory? My school believes in it but me not sure. I am neutral. If you believe in it can you please explain why? I am just interested inwhat theories everyone believes in? I am more curious about the people who don't believe in it. I just find this quiet interesting to talk about, and this is probably more debatble.

Hi I am 13 and just started putting my interest into astrophysics or what ever you call them scientist who studie space with all types of telecopes (that would be me if I know the name...). I just got a nice telescope its a 127 EQ Celestron Power Seeker. Its a reflector and some kind of light and energy asorber. What I mean is that my telescope is pretty powerful for $450 and especially for my age. I never been in a forum so my word usage on the internet is bad sorry. Now my question is, how do I find polaris in the sky with my naked eye in real life? I live in Queen Creek, Arizona and I see this pot like shape but the handle is bent upwards. Once I find the big dip…

Hi I am new to the forum and am not an overly intelligent individual, so I hope I don't bore you all with my mundane questions, I have so many but will try to keep them interesting... We know how fast light travels and we use that to determine the distance of the moon through reflectors and lasers etc, How do we determine the distance of Jupiter or the Andromeda Galaxy or Kepler 186F? Peter

As wikipedia says "A calendar is a system of organizing days for social, religious, commercial or administrative purposes. This is done by giving names to periods of time, typically days, weeks, months, and years. A date is the designation of a single, specific day within such a system. Periods in a calendar (such as years and months) are usually, though not necessarily, synchronized with the cycle of the sun or the moon." But why don't we get rid of the months? After all, they were based on the Moon's orbital period, but do we still need that today? Do we even need to think about them? As long as we know that a year is 365 days (apart from the leap year), isn't that eno…

What would happen if Jupiter's orbit started to decay? Would there be a point before which we'd feel no effect on Earth or would we experience something relatively soon (regardless of the relative positions of Earth and Jupiter in their orbits.)

I have gathered some questions that have been bothering me for quite a good time.I hope you can ansswer them and help me out. An one paragraph long answer is good enough, no need to go so deep in each one. This can take some time but I hope you'll learn a lot too by answering it --- 1. What if there IS a center of the Universe? By analyzing the cosmic microwave background, we can see microwaves that got redshifted due to the expansion of space, right? And the CMB forms like a sphere around the observable Universe, I assume. If we travelled billions of ly to any direction, the waves coming from that direction would be less redshifted than the ones on the other side, right…