Thursday, January 31, 2013

And the Winner is....

As you know the CANDELS team consists of many scientists who work on various aspects of galaxy evolution, supernova science and theory.

Rachel Somerville
Rachel Somerville is one of the theorists on the team. You can read a post in which she describes some of her work here. This month, she was awarded the Dannie Heineman Prize for Astrophysics. One outstanding astrophysicist is selected every year by the American Institute of Physics and the American Astronomical Society to honour his or her contribution to the field. Rachel received the prize for her work on semi-analytic galaxy formation models. In particular she has been working on  understanding the connection between galaxy evolution and the evolution of supermassive black holes. Within CANDELS she is combining the observational data with simulations and galaxy formation models to solve the puzzle of galaxy formation.

Like many astronomers, Rachel has lived and worked at quite a number of Institutes around the world, after receiving her PhD from the University of California in Santa Cruz. She is now a Full Professor and the Downsbrough Chair in Astrophysics at Rutgers University. Rachel is very happy and honored to receive this prestigious prize and for the recognition of her work. She said: "Working with observational collaborations has been my biggest source of inspiration over the course of my career. Being involved with the CANDELS project is particularly exciting for me because it has brought together observations at so many different wavelengths, as well as a large team of people with different interests and expertise, including a large number of theorists!"

The Heineman Prize is funded by the Heineman Foundation for Research, Educational, Charitable and Scientific Purposes, Inc. and is named after Dannie Heineman who as an engineer himself was a great advocate for science and education. This prize comes with $10,000 prize money and will be officially bestowed upon Rachel at a future AAS meeting. Since the first awardee in 1979, only 3 women (including Rachel) have received this prize, one of which was Sandy Faber who is also one of the CANDELS-PIs. Read more about Rachel and this prize here.

Sandy Faber
Sandy Faber, too, was recently honored. She is one of the 12 scientists to receive the National Medal of Science this year. The National Medal of Science is the highest award for scientists and engineers in the United States and was first awarded in 1963. Each year, scientists and engineers are honored for their outstanding contributions in various fields such as mathematics, physical, biological, social/behavioural sciences, engineering, chemistry and computing. The award ceremony for the National Medal of Science will be held at the White House tomorrow morning (Feb. 1) at 11am and you can watch it live here.

The CANDELS team is immensely proud to have such outstanding team members. Many congratulations to Rachel and Sandy!

Tuesday, January 29, 2013

Astronomy in the Alps

View of the Alps from the conference location in Italy
Image Credit: Janine Pforr
This week, about forty astronomers from all over the world are gathered in Sesto, Italy, a small town in the Alps to discuss the process of star formation in galaxies and how it has evolved over the history of the Universe. A great many of these astronomers are CANDELS team members who are presenting their own research based on CANDELS data. The meeting is being hosted by the Sexten Center for Astrophysics. The location is idyllic this time of year (see pictures) and is a premier hot spot for skiing. This remote location is perfect for a workshop like this because astronomers can really focus on the topic being discussed and can also socialize and have fun together.

The goal of the meeting is to understand star formation at high redshift, from z~2 galaxies all the way out to galaxies in the z~8 Universe. Astronomers from both CANDELS and many of the Herschel deep surveys are attending since all of these surveys are crucial for studying this topic. We are discussing various approaches to studying high redshift star formation, so in a few posts over the next couple of weeks, we will write about some of the interesting talks being presented.

Friday, January 25, 2013

The NASA Hyperwall at AAS

The NASA Hyperwall at the 2012 AAS meeting in Austin.
Image Credit
At this year's AAS meeting, the CANDELS team was given the opportunity to present the survey to the wider astronomical community by giving a presentation on the NASA Hyperwall. The NASA Hyperwall (shown to the right) is a set of nine high resolution screens put together to form a large display wall. It is taken to meetings like the AAS and set up in the exhibit hall. The high resolution (4104 x 2304 pixels) is fantastic for showing HD movies and animations and large astronomical images.

Janine Pforr, David Jones, and I gave the CANDELS presentation on the Wednesday of the meeting. The exhibit hall was full of people viewing posters at the time, so many people stopped by to watch our presentation. Janine kicked it off with a description of the CANDELS survey, our goals, and some of the science objectives that we have been discussing in various blog posts here. She showed the large color mosaic of GOODS-S and zoomed in to just a portion of the field so the audience could see the richness of the data set and many of the galaxies in detail. These images look fantastic on such a large screen and it was our first opportunity to see our data displayed this way. Janine also showed a couple of galaxy simulations (such as the one below).

Bolshoi Simulation: Bolshoi Fly-Through, by Anatoly Klypin and Joel Primack, visualized by Chris Henze, NASA Ames Research Center.

Next, I took that portion of the mosaic and zoomed into a handful of interesting objects to highlight some of our science goals and some of our papers. I showed the power of deep near-infrared imaging with a comparison of galaxies with very different morphology in the optical. I discussed the work that our group has been doing with galaxy morphology at high redshift and also highlighted the papers of Arjen van der Wel and Stijn Wuyts. Finally, David Jones wrapped up the presentation by discussing the results of the the supernovae part of the project.

In addition to CANDELS, both of the other multicycle treasury projects gave presentations. Julianne Dalcanton presented PHAT -- the Panchromatic Hubble Andromeda Treasury Survey. PHAT is imaging a large portion of the Andromeda Galaxy with Hubble in several different filters. With HST resolution, millions of individual stars can be identified and studied in great detail. The images that Julianne showed on the Hyperwall were stunning!

There was also a presentation on CLASH -- the Cluster Lensing And Supernova survey with Hubble -- PI: Marc Postman. CLASH is imaging 25 massive galaxy clusters with Hubble in order to map out the distribution of dark matter in great detail and study even more distant galaxies that have been gravitationally lensed by the mass of the cluster.

During the meeting there were many other amazing presentations on the Hyperwall. I particularly enjoyed the talk by Frank Summers from the Space Telescope Science Institute on astronomical visualizations. He showed many HST images as well as some fascinating movies that combine simulation data and real images in incredible ways. My personal favorite was the one shown below, which illustrates the entire merger sequence of galaxies by combining a merger simulation with HST images of galaxy mergers at various stages. This video looked great on such a large screen!

Galaxy Merger visualization of a supercomputer simulation illustrating the entire merger sequence. Credit: NASA, ESA, and F. Summers (STScI). Simulation Data: Chris Mihos (Case Western Reserve University) and Lars Hernquist (Harvard University)

We had a good time preparing our Hyperwall presentation and getting to see all of the other things people presented on the big screen. Part of the fun was that all of these talks were quite different from normal astronomical talks. These talks were really focused on the visuals with very little, if any, text on the screen. They were also aimed at a level that everyone, even non experts, could enjoy. I am looking forward to the creative things presented on the Hyperwall next year! 

Tuesday, January 22, 2013

AAS for a Grad Student

Hi, my name is Michael Peth and I am currently a graduate student of Astrophysics at Johns Hopkins University.  I'm working with Dr. Jennifer Lotz on the topic of Galaxy evolution and morphology in clusters as a member of the CANDELS team.  Which is basically a fancy way of saying I look at galaxies that are very close to each other (in a cluster) and from the shape, size and color I can determine a lot about their characteristics.  I am mostly looking for galaxies that have a supermassive black hole currently eating gas and stars, which causes it to shine brightly.  These types of galaxies are known as Active Galactic Nuclei (or AGNs).  A necessary aspect of research science is to present your work to the community as a whole. The American Astronomical Society (AAS) conference that was just held this month in Long Beach, California is a great  forum to let everyone know what your research has accomplished.  So I set out to attend this meeting and present my own research to an eager community.

Long Beach Harbor at Night looking out on the Queen Mary II Ship/Hotel
It's exciting to meet fellow astronomers outside the womb of academia (on the street, hotels, airport shuttles). It reminds me that I’m a part of something larger (which, really, is something that astronomers are constantly reminded of). For instance, after I arrived at LAX, I boarded a shuttle to Long Beach with 8 other people.  One of them happened to be a fellow astronomer. He said, "You expect to see fellow astronomers outside these conferences at a rate ~1/r^2".  I laughed because I got the joke.

Anyone who wishes to present their research at the AAS conference has the following options: 1) a Poster Presentation or 2) a 5-15 minute Research Talk. I decided that a poster made the most sense for me, since I had presented one last time I attended a AAS conference – in January 2010 – and knew what it entailed. The poster-making process is pretty straightforward. I quickly realized that the trick to crafting an effective poster is minimal text and plenty of graphs and diagrams – it may sound cliché, but a picture is worth a thousand words.

My Poster hanging in the conference hall
Before I tell you more about my experience, allow me to digress.  Three years ago, the AAS conference was in Washington, DC. At this time, I was an undergrad finishing my senior year at Penn State. I was also in the midst of applying to a slew of grad schools. I was hoping that, while I stood by my poster, I would have the opportunity to speak with some professors from the schools I was applying to. Even though I was stationed at my poster all day, only a few people asked me about my research. Only one of those people was a professor from a school I had applied to. Needless to say, I was a bit disappointed. However, when I look back on the experience, I really regret missing out on the morning and afternoon talks when I was guarding my poster. This time around, I knew that the best times to show off my research were from 9-10am (before talks begin) and from 4-6:30pm (after most talks are over).

When I tell non-astronomers (i.e., my family) about the poster session, they seem to think that I'm standing in a room with an audience, actively presenting my poster. However this is not the case.  Such an image is more akin to the 5 minute talks given. Poster sessions are different – we hang our work in the ballroom of the convention center and people intermittently walk by; they will occasionally ask questions if they are interested in your project. During the morning session, I was pretty much continually explaining my research to onlookers. The afternoon was somewhat less trafficked but I still was able to explain my research to multiple people. I was even able to meet one of my posters co-authors, who I had only previously interacted with via email. This part of the poster session is great for networking, in addition to seeing old friends and collaborators.

Long Beach Ferris Wheel outside the Convention Center
The poster session is not limited to single-entity astronomers and their research – it is also the domain of private companies, telescopes, publishers and other corporate entities. These groups have booths that detail their work, as well as offer a valuable opportunity to learn about potential employment outside of academia. But I would be remiss if I forgot to mention that these organizations offer plenty of swag. A highlight for many conferences-is the numerous free pens/stickers/posters/pins/laser pointers. One free product – the LED badge – even crossed over into wide usage for poster presenters. It’s basically a high-tech nametag, with an LED function that can be programmed to display any message you want. Many people programmed them to say things like, "Astronomy rules.”  It was an extremely nerdy (and therefore cool) utilization of the technology.

As I implied earlier, the research talks are the main attraction of the conference – when they are in session, most conference-goers are in attendance. I heard talks about galaxy evolution (which is my general research area), exoplanets, and even educational outreach. What many people don’t realize is that the Astronomy world is pretty disparate; people from different research areas seldom come together and share their work. For instance, I learned that, within 30 pc (or roughly 90 light years) there are potentially hundreds of Earth-like planets. This is a factoid that I wouldn’t discover within my own body of research, and it’s also something that reminds me how limitless, vast, and uncertain our field is.

One of the more social highlights of the week is the party that AAS always throws at a local nightclub. This year, the party took place at Sevilla, a Latin dance club just a few blocks from the convention center. It's always fun to see a bunch of awkward nerds cut loose. I always get the feeling that people view astronomers through the lens of The Big Bang Theory, and perceive us as socially incompetent nerds who take themselves too seriously and don’t know how to have a good time. If they had been privy to this party, they would see that they are only half-right: for the most part, we are socially awkward. But that never stops anyone from having a good time.

Soon enough, the conference came to a close. I felt like I learned a lot about Astronomy - especially subjects I don't primarily study. It invigorated my enthusiasm about the field in general and, although I had a great time, I felt excited to get back to Baltimore and continue on with my own research with this fresh perspective.

Thursday, January 17, 2013

3000 astronomers in Long Beach

Jelly fish at the Aquarium of the Pacific in Long Beach, CA
where the opening reception of the AAS meeting was held
Image credit: Jeyhan Kartaltepe

Last week many astronomers meet up again at the Winter meeting of the American Astronomical Society. You can read about the Summer AAS meeting in Alaska here. This time, the meeting took place for 4 days in Long Beach, CA. AAS meetings start officially with an opening reception on Sunday evening. Here astronomers have a chance to mingle and catch up with those friends and colleagues they don't see that often while having a bite to eat and a drink. This time the opening reception took place in the Aquarium of the Pacific which is located near the Convention Center where the rest of the meeting was held. The aquarium was a big hit with everyone since we were able to walk around the exhibition, look at lots of fish, jellyfish, crabs, shrimp and many other sea creatures. Some of them we were even allowed touch (of course under supervision of aquarium staff)! If you get a chance you should go visit, and then imagine the aquarium being packed with thousands of astronomers.

On Monday, the real meeting started with talks and poster presentations. Because so many people come together in one place, AAS meetings and their schedule are usually very busy. Lots of people give presentations (one usually has 5 minutes for a talk) or show a poster about their work. Since the meeting is only a few days long, talks are grouped into sessions according to their topic and many sessions run parallel.

Many of the CANDELS team members participated in the meeting. In fact, we had an entire talk session full of CANDELS Science talks on the first day. Our session was started off by Guillermo Barro who told us about his recent paper on the progenitors of compact quiescent (no longer star forming) galaxies. It is still unclear how such massive and yet extraordinarily small and compact galaxies formed. So some astronomers, like Guillermo, are looking for the progenitors as predicted by different evolutionary scenarios. 

Next, Jeyhan Kartaltepe presented her work on the morphologies of extremely luminous infrared galaxies. By using the extensive morphological classification scheme in CANDELS she compared the morphologies of luminous galaxies at different redshifts in order to determine how the role of galaxy mergers has changed over cosmic time. Mark Mozena then presented his dissertation work in a 15 minute talk. He discussed how he is using the CANDELS classifications to learn about the morphologies of redshift 2 galaxies. He also compared the morphologies of observed galaxies with those of model galaxies using the same classifications.

Christopher Conselice presented the cosmological implications of major and minor mergers by investigating the merger histories of galaxies across time. In particular he showed how mergers can be identified through measurements of morphology.  

Then Viviana Acquaviva and I talked about the difficulties in determining the redshift of galaxies using only photometric data and spectral energy distribution fitting. My talk focused on the treatment of very dusty galaxies while her's introduced the use of reasonable assumptions in the derivation of photometric redshifts with her code that is based on a Markov Chain Monte Carlo (MCMC) technique.

Janine Pforr standing in front of the poster presenting the CANDELS blog
during the AAS meeting in Long Beach, CA. Image
Credit: Jeyhan Kartaltepe
The session was finished off by Carlos Vargas on the question of whether data stacking (i.e. the adding up of lots of images or spectra) helps in the analysis of Lyman alpha emitting galaxies which are very faint at high redshift and only stick out due to their strong Lyman alpha emission. In particular, he discussed how different stacking methods frequently used to enhance data and study the average properties of such galaxies affect the result.

But Monday was not only a busy day in terms of oral presentations of the CANDELS team. We also presented a poster about this blog (shown to the left). This gave us a great opportunity to share the blog with the larger astronomical community, meet new people that are interested in blogs and public outreach, and discuss ways to improve the blog. It was a great day to start off the meeting and we will tell you more about the remaining days of the meeting in the next few posts.