Friday, January 31, 2014

Scale of the Universe

One thing that can be difficult to grasp in astronomy is the distance scales involved.  This Flash animation helps give a sense of some of those scales.  Sorry for the ads by the way.  It appears that the original website is no longer being maintained.

The animation begins at a 1 meter scale, showing the size of familiar objects like a beach ball or an average-sized person.  If you move the slider at the bottom to the right, it increases the length scale displayed in the bottom right corner of the animation), expanding the view outwards.  You begin to see larger animals, then buildings.  Zooming out past the 1km level, you see some smaller astronomical bodies, such as Mars' moon Diemos and Halley's comet shown together with geological features on Earth.

White Dwarf Size
White Dwarf Size Comparison
To see the first star in the animation, the white dwarf Sirius B, you need to zoom out to around 10^7 meters. There, you can see that it is not much larger than Earth and smaller than the gas giants in our solar system (and apparently also the Minecraft world).  You continue seeing larger stars until 10^12 meters, at which scale they are compared to the size of our entire solar system.

Continuing to zoom out, you see nebulae of increasing size.  While not photorealistic, I think the diagrams of these look particularly nice.  It continues extending out to show galaxies, clusters of galaxies, and superclusters.  The final limit is 10^27 meters with "the estimated size of the universe."

If you move the slider to the left, you can move into the world of the very small.  This includes scales from the microscopic to the subatomic.  Rather than trying to describe any other comparisons I find interesting, I'll just say it's definitely worth a few minutes to takes a look (assuming you haven't already).

Wednesday, January 29, 2014

Images of scientists

I was thinking about the subject matter for my new post. And I came across the blog post that is linked below.
http://scienceblogs.com/framing-science/2010/05/05/reconsidering-the-image-of-sci/
This blog is talking about how the image of scientists is changing in movies and television over time. It is a very interesting blog that talks about how the scientists are shown more in positive light in present cinema and television. So I thought that I should compare characters from two of my favourite comedy series.
 First I want to talk about very popular show The big bang theory.

It is one of the popular comedy series running right now. I admit I love this show and I watch it regularly. But let's think about the characters in the show. I understand since it is a comedy show, you portray the characters as funny as you could make. However, since this show is popular among masses, it is conforming the stereotypes we already have about the scientists. The show consist of six scientists and one waitress. All the six scientists are socially awkward, although the intensity is different. None of them are good at communicating. They have no social life other than video games and sci-fi movies. It is very difficult for them to find any date. These things are conforming the stereotypes we already have. Well I know many of you might think why this even matter. I wanted to talk about this because the article I have linked below talks about why there are so few women in sciences. There are many interesting stuffs in it. One thing I remember after reading this article was that some woman was scared to say she was a physics major. She thought she might not get a date after that.
http://www.nytimes.com/2013/10/06/magazine/why-are-there-still-so-few-women-in-science.html?pagewanted=1&_r=1&
I guess once you are matured enough these stuffs doesn't matter, but for younger generation who are deciding what to study in college these things are important. Lets admit most of us want to look good or at least normal most of the time.
Now I want to talk about the character Ross in the show Friends.

Ross is a palaeontologist in the show. His character is very nerdy but at the same time he is very normal person. He has passion for the work he does, and will jump into discussion with friends about the science he loves. But he also jokes, goes out and date people. As in the image he is very excited about the tie with dinosaurs. I feel I can relate to his character much more than any one character of the big bang theory. Even though we love our work and act crazy sometimes, we are normal most of the time.
 It would be so much better if scientists were  portrayed more as Ross rather than a character of The big bang theory. This would help to get rid of the stereotypes we have and also encourage lots of younger people to study science in general.
Here are some links to videos from the two television shows to differentiate the portrayal of characters and for some laughs.
http://www.youtube.com/watch?v=yS-ameyp9Ag
http://www.youtube.com/watch?v=cXr2kF0zEgI


Which is your favourite scientist television character?

Monday, January 27, 2014

The Wonderful World of LaTex


Have you ever heard of LaTex? Don’t worry, in the grand scheme of things, not many people have. It is largely used within the mathematics and some of the scientific communities to write peer-reviewed journal articles or make snazzy looking presentations. LaTex is a masochist’s version of Microsoft Word/PowerPoint but I mean that in the best way possible. You are writing a code to compile your document with special LaTex syntax. According to the official LaTex website, “LaTex is a document preparation system and document markup language. LaTeX uses the TeX typesetting program for formatting its output, and is itself written in the TeX macro language. LaTeX is not the name of a particular editing program, but refers to the encoding or tagging conventions that are used in LaTeX documents.

So why should you care about LaTex when you have gotten so used to making your documents in Microsoft Word? Because it will change your life. Sure, there is a learning curve to it and even though I have been using it for years to write everything, I still consult the Comprehensive LaTex Symbols PDF regularly, but my documents look beautiful. It is a harsh world out there, especially if you are apply for funding (scholarships, fellowships, anything where you turn in a document). When it comes down to it, presentation not just the quality of writing, matters.

Now that I have convinced you that you should probably look into this, I have news for you. It is FREE! Just go here to download. It is fairly easy to download and install. 

Now it is time to start creating. Like I said earlier, there is a learning curve. From Wikipedia, here is what an example document looks like:


On the left is what you type. On the right is what compiles as a PDF.
I would just start with looking for examples, such as this one, from around the web. The best way to learn a programming language is just to start programing. As you become more experienced and creating a vast array of documents, you will build up your own library so you will never have to start from scratch.

My motivation for writing a blog entry about LaTex came from the discovery of interesting new ways to use LaTex.

First, is GmailTex. It is LaTex for Gmail and it is also FREE!! You can download it through the Chrome App Store. You will need to clear your cookies and restart Chrome to get it to work, but it is worth it. Now, if you are trying to ask for help on a homework assignment or something for work, everything can be spelled out in a nice and ordered format.

Second, WriteTex. Do you have a group assignment/project, want it to look nice, and have everyone working on it at the same time (like documents on GoogleDrive)? No problem. WriteTex can do it and it is also FREE! Of course, everyone will have to know how to use LaTex. If someone in your group doesn't, this is a perfect opportunity to enlighten them!


Note, resumes and CVs look amazing in LaTex too!

Friday, January 24, 2014

Even More Citizen Science

Continuing on the same thread as my last post, I'd like to point out another way for anyone to contribute to science.  I have been personally involved with BOINC distributed computing for a number of years.  Unlike with Galaxy Zoo, you aren't doing the science with BOINC, your computer is.  While it originated at the same lab at the University of California - Berkeley where the well-known SETI@home is based, you can do much more than search for extraterrestrial life using BOINC.

Einstein@Home Graphics
The Einstein@Home Screensaver (detailed description)
One astronomy-related project is Einstein@Home, which searches for gravitational waves from spinning neutron stars, called pulsars.  The name comes from the fact that Albert Einstein first predicted their existence based on his theory of general relativity.  Einstein@home uses data from 3 gravitational-wave detectors to conduct its search, namely the LIGO Hanford and Livingston interferometers in the United States and GEO600 in Germany.  The image to the right shows a portion of the search in progress.  It includes a celestial sphere with major constellations for reference.  The small purple dots are known pulsars and the red ones are supernova remnants.  The orange marker shows the area of the sky that is currently being searched.

Einstein@Home Fermi Pulsar MapLike all other attempts to find gravitational waves, Einstein@home has not made a direct detection yet.  However, the project has also begun incorporating data from the Arecibo radio telescope and Fermi gamma-ray satellite, which has lead to the discovery of over 3 dozen new pulsars.   The latest publication of pulsar detections was last November, in this paper, announcing the discovery of 4 gamma-ray pulsars.  The accompanying press release includes images like the map of the pulsars shown here and even a photo of one of the discoverers (a person running Einstein@Home on his home computer).

Another BOINC astronomy project is called MilkyWay@Home.  This, not surprisingly, runs models to tell us about the structure of the MilkyWay galaxy.  One approach MilkyWay@Home uses is to utilize evolutionary and genetic algortihms to simulate galaxy formation and mergers.  Another approach is to use N-body simulations (as shown in the animation on the left), to model collisions between dwarf galaxies and the MilkyWay.  As described on the project science page, the data is helping to build an accurate 3D model of the MilkyWay.

As you might imagine, BOINC projects exist in many fields other than astronomy.  Rather than attempting to summarize more, I'll just link to the official list.

One thing about some BOINC projects that surprises me as someone who has studied computer science is how efficient their code is.  Distributed computing offers a massive amount of computing power, but with major caveats.  I like to think of it as a massive distributed memory system with each person's computer as a node.  But unlike a normal cluster, there is no inter-node communication and a node may never return a result - or worse, return one that is completely wrong.  So, kudos to the collaboration of scientists and volunteers that has made this combination work and produced good science in the process.

Wednesday, January 22, 2014

Supernova in M82!

A Type Ia supernova has gone off in the very nearby galaxy M82! Details here, from Paul Sutherland at Skymania.

If you're short on time, here's the kicker:

Brad said the supernova appeared to have been caught early and so might brighten to magnitude 8 which would put it easily within the reach of binoculars.

Wow!

Photo by UCL/University of London Observatory/Steve Fossey/Ben Cooke/Guy Pollack/Matthew Wilde/Thomas Wright

Another interesting aspect of this story is that the supernova was discovered by amateurs:


This could turn out to be a pretty amazing astronomical event.

Update: Here's another nice post about the new supernova, from Phil Plait (aka the Bad Astronomer), with some further links. Latest word on Twitter has an estimate of the peak magnitude:


We know pretty well how these Type Ia supernovae behave over time, so this estimate is likely pretty reliable. Magnitude 9.5 is getting pretty faint for binoculars, unfortunately. But maybe Chamberlin Observatory can take a look for us!

Update 2: Turns out the supernova (now officially named SN 2014J) was not only discovered by amateurs, it was discovered by undergrads! Awesome story here!

Tuesday, January 21, 2014

Impacts of astronomy

Ancient Greeks used lead-sheathed iron reinforcements to prevent rust.
The Parthenon in Athens



In my second post I want to talk about some of the other inventions possible due to astronomy research. In this search  I found some sites which enlists the inventions but when I tried to read more about it, there is very few information that links them  to astronomy research. I think it would be much better if astronomy was given due credits for these inventions. This way when people look up these important technologies, they can see how these inventions were influenced by astronomy. When writing this blog I am having hard time to give details on how these inventions were influenced by astronomy.
Anyway I will continue the list. I guess one of the most important will be the invention of WLAN (Wireless Local Area Network). This links two or more devices, thus we can use the same internet connection in different computers. It is a type of local area network which uses high frequency radio waves instead of wires for the connections among different devices.
From security to archaeological study, there are instruments influenced by the technologies used in astronomy. The X-ray observatory technologies used in astronomy is also used in checking of baggages in airport.
scienceline.org

Gamma ray spectrometer was originally developed to study lunar soil is now used to study historical buildings and do renovations. For example, the Parthenon in Athens was renovated using this technology. Gamma ray spectrometer was used to identify iron in the building and substitute it by titanium.
There are many other inventions you can find elaborated in
http://www.iau.org/public/themes/why_is_astronomy_important/
Astronomy is a vast subject which helps to answer many questions which we humans had since the beginning of the civilization. Although it is interesting and informative, there are times people want to know how it impacts the everyday life.
How many of you have been asked this question?

Book Review: How I Killed Pluto and Why It Had It Coming

Although most of our time as graduate students is taken up with problem sets, teaching, and research, it's nice to try to pursue our love of astronomy outside of school as well.  I love reading, and about a year ago I read a fantastic book called How I Killed Pluto and Why It Had It Coming by Mike Brown.  Dr. Brown is an astronomer whose discoveries of other objects in the Kuiper Belt played a huge role in demoting Pluto to the status of Dwarf Planet.

From the point of view of an astronomer, reading this book was very interesting.  I of course knew the (very) basic reasons for Pluto's current status, but I didn't know how in depth the full story was, or how political the entire process became.  Dr. Brown does a great job of stepping you through the storyline from the very beginning of his interest in searching for other planets in our solar system.  But you don't need to be an astronomer or even a scientist to appreciate this book -- my mom (a lawyer with no scientific background) recommended it to me in the first place, and she couldn't put it down.  Dr. Brown includes bits of his personal life (including some struggles in balancing professional and home life) which really make the story compelling for the reader. His explanations are basic enough for non-scientists, but include enough science to keep us astronomers happy. And, as you can tell from the title, he has a great sense of humor!

Another reason I loved the book was the honesty with which Dr. Brown discusses his research process. Many of us have heard of "imposter syndrome" -- the feeling that we aren't good enough to be where we are and doing what we're doing, and that some day someone will figure that out.  I deal with this quite often in classes and in my research, and it's easy to feel alone and, quite frankly, stupid.  (Although being in a fantastic graduate department with supportive faculty and fellow grad students has helped tremendously!)  Dr. Brown, who is without a doubt a very impressive researcher and professor at Cal Tech, discusses feeling completely lost in his research at times, and not at all knowing what to do.  I was shocked to read this -- how could someone who has truly "made it" in his career feel this way?  But the truth is most of us do at some point, and it was encouraging to realize that these feelings are prevalent nearly everywhere, not just in my own head.

This book has been around for a few years so I'm sure many of you have read it already, but if you haven't, definitely pick it up!

What are your favorite astronomy-related reads?

Monday, January 20, 2014

Archival jackpot

Brandon’s post concerning Galaxy Zoo was a great reminder of the programs available for anyone and everyone to be involved in the astronomical discovery process. There was a recent Astronomy Picture Of the Day (APOD) submitted by a philosophy professor that compiled four images from the Voyager spacecraft (on August 24, 1989). The image is included as Figure 1 this post, but can also be found here.
Figure 1. Neptune's moon, Despina, casts a shado on the gas giant. Image compiled from 4 archival images from the Voyager spacecraft by Ted Stryk (a philosophy professor).
There is just so much astronomical data out there! And many of the publically-funded projects are required to release the data and images for public use—yes, anyone can use it. This data is referred to as archival. For example, the Hubble Space Telescope has its site where you can download thousands of images and lots of archived data. Many other space and ground-based telescopes have archived their data. And this is not just a fun thing for the public; it is also very convenient for astronomy researchers as well. I have read many papers that have solely used this archived data for their analysis. Brian Kloppenborg, who received his PhD from DU a couple of years ago, was able to find almost 200 years of archived data on the star system he was studying, epsilon Aurigae. The data wasn’t exactly ideal, but it is hard to beat the amount of time epsilon Aurigae has been observed. Funny thing about that object: we still have dozens of questions! So, not all the answers will be found there, but it should be helpful.

I guess this is a plug for both public citizens and astronomy researchers to use the available archives. I need to use it more in my own research. It is a great resource and provides lots of evidence for observation proposals, eg I need to observe [object] at [wavelength], especially because there is no equivalent archival data.

Has anyone effectively used the archives in their research?