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Comment Re:You think that's big!?!?!? (Score 1) 202

While you are completely correct, it is harder and harder to see individual stars as you observe galaxies farther away. The farthest we can clearly observe bright, single stars is the Virgo Cluster which is only 50 million light years away. So until we get much larger telescopes we have to rely on the local universe to provide us with record breakers or we are sunk for the time being.

Comment Re:Ten million times brighter than the Sun? (Score 1) 202

If I have 1 100W bulb and compare it to 2 100W bulbs, a single patch of surface area will not be intrinsically brighter but the object with two bulbs is twice as bright. I posted about this elsewhere on this page already, but luminosity is equal to the surface area (A) times the Temperature(T) to the 4th power. L=A*T^4. Every lightbulb has the same temperature but as you add lightbulbs together the emitting area goes up. If you took a star like our sun, kept the surface temperature the same but made it a million times bigger in size, the luminosity would go up 1 million times.

Comment Re:Ten million times brighter than the Sun? (Score 1) 202

Spectroscopy, modeling, and relative photometry. Many of the brightest stars in R136 have been well studied and by comparing brightness at the same distance you can measure the luminosity. That said, you might like to know what has happened to most of the previously discovered most massive stars. With the advent of larger and space telescopes, the HUGE stars were found to be very very tight binaries that were not resolved as individual stars previously.

Comment Re:Amusing (Score 1) 202

Additionally, there is the bogus idea that a revised theory should still be considered a theory. Instead a revised theory is now no more than a hypothesis, requiring fresh predictions (to be tested against new observation not previous data) and verification and requiring the fresh application of Occam's Razor (since a revised theory is also usually going to have additional complexity to patch up the previous theory).

While I cannot completely disagree with your argument, theories are just that, a working hypothesis. We have a model that describes everything that happens in the universe around us. We call this model a theory. It does an amazing job predicting 99.999% of everything we see. Then someone makes a discovery that contradicts some of the assumptions and outcomes of the theory. We go back, look at the physics, and adjust/revise, the theory so it can explain all of the observations. Its not that the theory is broken or is wrong, it could not describe EVERYTHING. Every theory must explain existing data as a start and then make predictions about the data we will take in the future. A great way to test a theory is to see if it can model existing data. The data don't change because you changed your theory but if you need to make a new prediction then you need new data to test that piece. A good example of this is Newton's Laws of Gravity. NO ONE can argue that gravity exists and that Newton's Laws work for almost everything. Well they didn't work for Mercury's orbit. When they compared the predictions of Mercury's orbit from Newton's Laws, they found that the model was off by 43 arcseconds every centrury. Does that mean Newton's laws don't work here on Earth? No, it means we needed a new model of how gravity worked in more extreme situations. This is where Einstein's Theory of General Relativity comes in. It explained the precession right away and we have used Relativity since then to explain motions around black holes and other extreme objects. Newton's Laws still work perfectly fine with in the errors of measurement for everything else.

Comment Re:VY Canis Majoris (Score 3, Informative) 202

You are correct! I am an astronomer and want to straighten out a few things. When it comes to stars, MASS is what matters. Mass governs the size, lifetime, luminosity, and temperature of the star. To form a star gas clouds in the galaxy slowly collapse under their own gravity and form dense clumps, these clumps continue to collapse sometimes forming a single or multiple stars. In the centers of the largest star forming regions, these clumps are very dense and are close to each other which increases the probability that they will bump into each other and combine. This is one theory of how we can form the most massive stars, where several smaller, say 50-100 solar mass stars get squished together to form a so called 'hyper star' of several hundred solar masses. Once the star is formed it is on what we call the 'Main Sequence' where it will fuse hydrogen into helium in its core. At this time the star will have the hottest surface temperature of its life as well as the smallest physical size for its evolution. The reason a 'smaller' sized star can be so bright is the fact that luminosity (L) is related to the star's surface area (A) times the surface temperature (T) to the 4th power (L=A*T^4). Because this star is so hot, it can be 10 million times brighter than our sun but is maybe 10-100 times the physical size (radius). To continue evolving the star, as it ages the star will "puff up" and cool becoming a red hypergiant in this case. This is after it has used up all the hydrogen in its core. The star is headed for death but seems to keep roughly the same luminosity as it cools down and expands. If it cools from 80,000 Kelvin to 3,000 Kelvin then it must expand to 500,000 times its original surface area or 700 time larger in radius. This is why stars like VY CMaj and Alpha Ori (Betelgeuse) are so astronomically huge. They do not have to be extremely massive to become incredibly large in radius. VY CMaj is only 25 times the mass of our sun and is mind-bogglingly HUGE. Think of what a star 10 times more massive would look like when its on its death bed. If you live in the southern hemisphere when this new star dies, you will certainly see the supernova with your naked eye. So while in size this new star seems to be small in comparison to some nearby giants, when it is compared side by side its beyond anything we have seen before.

Comment LISA vs. Pulsar Observations (Score 3, Informative) 109

Just to let you all know, LISA and the Pulsar observations are not observing the same things. Sure they are fighting to detect the first gravitational waves but they are looking at different regimes. Its like comparing the GBT radio telescope to Hubble, they are fundamentally different even if they are looking for the same type of objects. http://www.physik.hu-berlin.de/qom/research/freqref/lisa explains what frequencies LISA will be sensitive to. The Pulsar array is most sensitive to 10^-4 where as LISA is higher frequencies. LIGO is even higher in frequency. You learn about different objects and new phenomena by studying ALL frequencies available to you. Many astronomy projects are expensive as hell but they develop new technologies that benefit our daily lives. Who knows what laser interferometry in space will generate for the public funding the project.

Comment Re:Location (Score 1) 750

While I am not 100% sure of the receiver technology, 3G only gives you triangulation information where as GPS is a completely different system. They may use the same antenna and thus the iPad wont have GPS but they are fundamentally different. GPS is from satellites and can be stand alone and 3G triangulation while not the same quality as actual GPS works pretty much as well as anyone would need it to to figure out where you are on google maps. Wifi info is always available so unless the ISP only relays the information about where its headquartered (my parent's does this) it should give you a good locator.

Comment Why doesn't it run OSX? (Score 1) 750

My question to this whole deal is why does the iPad not run true OSX? I would have bought one the first day if it was a real tablet that ran all of the software i need. I am a graduate student so being able to code and work over X11 is imperative. I also do a lot of data management hence the need for a finder and Desktop etc. I would have wet myself if we had received a tablet that was capable of everything the standard mac was able to do AND had an i-pad mode where it had supreme battery life and access to a few lightweight apps. Yes I am asking for the best of both worlds but Apple is more than capable of providing both and making it work. Take a leap on the development of something new not just give the iPhone some growth hormones. When the iPad becomes useful to more than the casual user I still want to be on board but until then **fist shaking**.

Comment Just look up! (Score 1) 377

I am a graduate student in astronomy and I am very active in astronomy education and outreach. There are a lot of things you can do with students with a very small set of tools. In addition to your telescope I would either bring or encourage students to bring: 1. Binoculars 2. Flashlight (red led OR take a regular flashlight and cover in several layers of red cellophane) 3. an open mind If you then bring the Astronomical Almanac and a planisphere (star chart) you can find many of the great objects in the sky. Looking at bright stars that have different colors is a great way to start talking about what's in the sky. Betelgeuse and Rigel are great for this and they are up at the right time of night in the spring. Another great binary star is Alberio in Cygnus. It is a double star that is a K spectral type and a B spectral type (orange and blue in color). You can see them through binoculars so it should not be hard to point the telescope at it. Almost all of the Messier catalog objects should be visible with a 4-inch telescope even if they are not magnificent. This may be a way of talking to students about how a telescope works and why astronomers want better cameras and bigger mirrors. If you have students learning some of the objects in the night sky and able to point to them with and without a telescope I think you will be doing well. http://www.heavens-above.com/ is a great website that will tell you about all fly overs of the space station, Hubble, and any iridium flashes. Some of these flashes are quite spectacular. While you cannot see these in the telescope they are fun. As for planets, no matter what telescope you use none of them are truly spectacular. As the aperture grows the amount of detail you "can" see will go up because you are collecting more light but the atmosphere will blur the images more as well. So it is a toss up at some level. I love looking at solar system objects just to see what I can see. The moon is fascinating and you can make good use of the night/day boundary to teach about mountains, shadows, and how Galileo proved the moon is a flawed object. But really my advice is to try it and look up with your students. Best of luck!

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