It is the work of Dr. Prather and his research group.

I am a graduate student in Astronomy and part of my dissertation is studying these active engagement techniques. It seems that many people on here are quick to jump the gun and give an opinion before understanding why we say the lecture doesn't matter anymore. Teachers in the workshops I help with also get confused as to what these words mean.

People learn in a variety of different ways yet lecture is the most common form of material dissemination. This is wonderful for the people who can soak in all of the information and draw conclusions themselves. This leaves many people behind if all they have time for is writing down facts and attempting to keep up with the basic material. Since most courses in high school and college no longer require intense critical thinking, a quick memorization of facts will allow most students to succeed and think they "KNOW" material. When asked to apply it many are unable to. Interactive engagement techniques do not require the removal of lecture from the learning process they just put less emphasis on it. Lecture is the ONLY way to present enough material in a college course and is critical to the active engagement techniques. Students must be given the basic knowledge before they can be left to begin their own critical thinking process.

We know from research that people learn by linking new concepts to concepts they already have a model for. Most of these models are incorrect when it comes to astronomical and physical phenomena. A student who has misconceptions may still think they understand the material and be able to respond correctly to some questions. However, when a question specifically calls out a known misconception, the model the student is using to reason through the question will lead them to the incorrect answer every time. What active engagement techniques employ is social conversation. Lecture tutorials are one form of this learner centered engagement. Students are given a 20 minute lecture on a topic such as the seasons. Then they spend 20 minutes with a partner working through a socratic dialog (in their lecture tutorial workbook made up of research validated questions and "fake" student responses). The pair works on coming to consensus and discussing the reasons for their answers on each question. As the students work through the dialog the concepts become more challenging and the misconceptions are challenged. Often students are required to look back at previous answers (known to be commonly incorrect) after some misconceptions have been challenged. Students are engaged in their own meta-cognition and are forced to confront their own and others ideas. This active form of discussing and defending your ideas allows for misconceptions to be overcome and new concepts to be better rooted in the brain.

For those of you who think this is useless. We performed a study of lecture tutorials in our classes. We split the classes into the top 50% of students and the bottom 50% of students. Before lecture the top students are scoring 50% on concepts not yet covered, those at the bottom are near 10%. After lecture BOTH groups are around 50-55%. This means lecture is helping students catch up with the basic information they may not have had. However lecture only got the class to FAILING! After a lecture tutorial in class, both groups are now performing at the 70% level. TWO WHOLE LETTER GRADES BETTER!!! This is why we say lecture is not the important part of the course because the student engagement is helping everyone.

So if lecture is only a means of giving out the information then there is not a critical need for professors to stand in front of the classroom at this time. We can hire actors which are far better at the job of dictating and making material exciting and record it. The professors job becomes important later when students have questions not for being the talking head.

Plex changed last month. See Dev Blogs.

13.7 Billion light years to the edge of your visible universe.

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.

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.

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.

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.

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.

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.

This is why people need to know fractions!!!! If only i could convince my college class that this was important. :(

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.

Its perfect to embed into a table at an internet cafe.

While I do agree with you, even small amounts of weight when carried for a long time will cause fatigue. Either way its probably not good for you to wander the hall typing for hours on end.