Found by JMU physics major: A triple Supermassive Black Hole system

Congratulations: Our own junior physics major Jenna Harvey co-authored a paper describing the fantastic discovery of a system of three supermassive black holes on a close collision course!

This work, which just appeared in the Astrophysical Journal, was led by graduate student Ryan Pfeifle, under the advising of Prof. Shobita Satyapal of George Mason University, and involves a team of scientists who put together observations and measurements from quite a variety of telescopes, both ground and space based.




The massive crash of three galaxies at the center of which this triple accreting supermassive black hole system has been discovered was found thanks to new techniques that exploited the power of infrared light to peer through cosmic dust that usually enshrouds, and thus hides, newly activated black holes that just started sucking matter onto them.

The paper that describes this discovery, which Jenna co-authored, provides one of the strongest observational evidence to date for such a triple interacting galaxy system, which has eluded us until now.

Jenna's contribution to this work, under the advice of professor Anca Constantin, entailed analysis of observations from the Large Binocular Telescope Observatory (LBT).  Jenna worked on the LBT data the collaboration has for a sample of fifteen interacting galaxy pairs, and found that in one of these systems, that showed an unusual ensemble of three X-ray nuclear sources, gas is swirling at speeds of thousands of km/s (which is just a fraction of the speed of light), proving that it is through galaxy collisions events like this one that black holes begin to actively snack and therefore grow, maybe before they merge onto a larger one.

An overview of Jenna's work on the whole sample of interacting galaxies that hosted this unusual discovery can be seen in the poster that she presented at the end of summer 2019 at the Undergraduate Research Symposium.

This discovery has gotten a lot of press already, check them all out: NASA press release, CNN, Space.com, The Register (UK), VICE, a German newspaper, the LBT site, and you might even have heard about it already from Fox and MSN.

Way to go Jenna!

Our Students Visit and Observe at the Green Bank Observatory

Being able to breathe a few steps away from the largest steerable thing on the surface of Earth is something an astronomy minor would not say no to, especially if that thing is a telescope which has the power to answer mankind's biggest questions.

We are talking here about the Robert C. Bird Green Bank Telescope, the site of which (The Green Bank Observatory, or GBO) our astronomy minors had the chance to visit and explore.     Eighteen of our students were accompanied by four faculty members for an overnight trip there, where they got the chance to observe with GBO's 40-foot teaching telescope and participate in quite a number of other educational programs.

Overall, the experience seemed to be overwhelmingly positive: one might not get the chance to see so many smiles and hear "wow"s from physics, computer science, or engineering majors, all while learning about the our host galaxy, Milky Way, through their own observations of Hydrogen emission.

Far away from hot O and B-type stars, the hydrogen in space is in the ground (i.e., lowest energy) state.   However, when the spin of the electron flips from being parallel to anti-parallel with the spin of the proton, there is a tiny energy difference that is emitted at the wavelength of 21 cm (or a frequency of 1420.4 MHz).   While a hydrogen atom can wait on average a few million years before it undergoes this transition (YES, it is this rare!), the large amount of hydrogen gas makes this particular emission one of the most prominent and easiest to detect with radio telescopes.

The 40-foot spectrometer allows us to detect radio waves from this particular transition by
blocking (filtering) out all of the waves but the ones coming at this exact frequency.  This 21-cm line radiation provides the best way to map the structure of the Galaxy (note: for astronomers, Milky Way is the only galaxy with capital "G").

Here is an example of detection of (the center of the) Milky Way's emission at 21 cm with the 40-foot telescope's spectrometer (sorry folks! no pic from there). The red line is a calibration measure, while the black line records the data, i.e., the intensity (in Jansky units) as a function of frequency.  The two  strong peaks at the left side of the spectrum show detection of HI at two different frequencies: the strongest peak is located at 1419.5 MHz, and the other at 1485 MHz, depicting two different clouds of Hydrogen emitting the 21-cm transition that is redshfited (smaller frequency, or longer wavelength), implying that the detected Hydrogen is moving away from us (while rotating in the disk of the Galaxy).   The peak at the far right depicts an artificially created signal of 500 Jy, for calibration purposes.

Multiple data sets from eight groups of students, acquired during the night, were collectively analyzed the next morning.   After not much debate, there was a pretty good agreement that the data shows strong evidence that Milky Way has the shape of a flat disk, that is rotating counterclockwise.

Here are some of the students' thoughts about this trip, with some cool, funny, or downright amazing things they have learnt:

* Mary Ogborn & Ebony Williams (physics majors):  This trip really illustrated aspects of radio astronomy that I wasn’t aware of before. Although I was aware of radio interference, I was not aware of how sensitive these telescopes could be to various sources [...] The control room was also impressive, as it was copper-insulated, in order to keep in the radio waves coming from all the computers and machines. [...] it was interesting to step into the past and see how the original radio astronomers operated these huge telescopes. I can’t imagine having to manually dial in the declinations, change the frequency every second by pushing the mark button, and having the chart reader draw out the peaks without any other form of labelling. [...] I now understand how observatories in the past would hire people to be ‘computers’ before the advent of computers.

*Ryan Ferrell (physics major):  I did not expect to be able to extract this much information from the data which made me appreciate how much information can be brought out of even just a little data.[...] I learned was how many common things cause radio interference. I knew previously that most electronics caused radio interference, however I did not know that signals from modern electronics are a billion times stronger than the radio waves that the GBT was measuring from the Milky Way. [...] I never knew the GBT was the largest radio telescope in the world or that the Drake Equation had been thought of there. [...] I was very surprised to find the control center so close and surrounded in a giant Faraday Box. 


* Tanna Walters (engineering major) & Brandon O'Neal (physics major):  This trip to Greenbank Observatory has taught us a good bit about the actual ways in which the data is collected and how the hardware works.  GBT actually has a clam-shaped dish and an arm that is off-center that collects the radio waves. The purpose for this is to allow for the collection of more radio waves as opposed to parabolic telescopes that have the receiver in the middle of the dish, blocking a significant portion of the incoming radio waves.   [...] we learned just how sensitive the telescopes are to interference (RFI). Even taking a picture with our phones could interfere and ruin astronomers’ data all over the world. 

In the control room of the GBT

* Tom Gagne (computer science major) & Kris Pickens (physics major):  We learned the remarkable fact that if a cell phone were placed as far away as Mars, it would still outshine the brightest distant radio sources by several orders of magnitude.  So we had to turn them off when out among the telescopes. We also learned that a shipbuilding company built one of the telescopes and put an enormous ball-bearing in it. The ball-bearing was so large that the bridges had to be fortified along the path of the train that took it there. 

* Cameron Kelahan (computer science major):  For the first time, I was able to operate a radio telescope and perform radio astronomy. I learned how to operate a 40 foot radio telescope, the equipment that goes along with it, the meaning and importance behind the 21 cm line, and how the shape of the Milky Way was originally discovered. I also got an idea of what it may be like to work at an observatory from talking with [GBT operator].  His job seems very interesting and also challenging! 12 hour shifts are something one can get used to, but there is also a lot of responsibility that goes into operating a MASSIVE TELESCOPE!  The overall experience [...] allowed me to strengthen friendships with classmates and possibly future colleagues while learning with them about something we all have a passion for.  

Physics weekend affairs again: the CAA Undergraduate Research Conference

The weekend of the April 13th-15th , I [Jimmy Corcoran, a junior physics major] had the opportunity to participate at the Colonial Academic Alliance (CAA) Undergraduate Research Conference [at Old Dominion University in Norfolk].  Initially I wasn't sure I was skeptical about whether or not I would enjoy the experience, but I was quickly reassured.  There were events spaced out throughout the entire weekend, enough so that you always knew you were kept in an academic mindset, but not so many that you felt overwhelmed and didn't have enough time to relax.  Everything over the course of the trip went smoothly, both of the keynote speakers were fantastic speakers and were able to captivate the entire audience, regardless of their academic focus; the spacing out of all of the student presentations, and even all of the meals prepared for everybody were fantastic.  Overall I thought it was really a fantastic experience to be around so many people involved in undergraduate research in their respective fields, and also for the opportunity to share the research I've been doing with my peers from the entire CAA.  

Jimmy  was one of the 3 physics majors representing JMU physics and astronomy undergraduate research (out of a total of 10 JMU selected undergraduates): Jimmy the astronomer was accompanied by Ethan Cummings and Thomas Hoke (both juniors) who presented their findings on some novel materials' behavior at this 10th annual CAA conference.   Here are the three of them ( ...musketeers in quest for scientific answers to how the world works):

and here are some details about their presentations, as described in the Madison Scholar. 

What can we say, they have their own ways of saving the world!

We heard not once that "they were excellent presenters!"

Over and Over... cast and solar viewing

Team Awestronomy's adventures again here, featuring:

Anthony (edible comets), Nathan (black holes & solar viewing), Jimmy (galaxies and sunspotter), Emil (REAL comets), Kyle (solar viewing), in no particular order, got their act together again, or we should say, over and over...cast...

OK, the weather did not cooperate with us yesterday (our planned last Saturday of March), the clouds roamed around the whole morning (sometimes quite menacingly: check out the sky in the pictures), leaving us with basically little chance to show the Sun off through our Coronado. Yep, no flares in sight this time...

Nevertheless, the Breeze (finally) got a handle of us a this event (can you spot the Breeze photographer in the crowd in the above picture?). Until the Breeze article sees the light, here are some snapshots of the goodies of the day:

The sunspotter spotted the clouds and some tree branches, which was still sort of cool... (not only little) people were still fascinated by this little simple device:

The comet making was a big success (again!), from enchanted audience by the setting up process to happy clients, I mean learners about what it takes to produce that comet tail, with both the edible models and the real -non-edible-ones:

(phufff, we were so lucky those meteorites fell on Earth right there near our Market booth and right then -- we're only there 10am-noon)

- anyway, if you're interested in the recipe, you just have to ask. we'll provide it, ~30 million times smaller than the actual one, but for sure with no delay..

wow! look at that tail...

Asteroid and crater production were also quite popular this Saturday:

.... and we also featured guest scientists with us presenting little motors powered by squishy circuits (just so you know how those gyros aboard satellites like the Hubble Space Telescope look like):

All in all, and you can go here to check out some more pictures about today's making of the comets (both types), asteroid and crater involvement, and even some close to successful picking through the telescope.

Flares, comets, asteroids...

Yes, once again (following event1 and event2), we took Astronomy to the Market. Last Saturday was the first in the new Spring 2012 series to feature safe solar observations, edible comets, asteroid collisions, along with answers, many answers to your questions about the Universe at the Harrisonburg Farmers Market. The plan is to show off our science corner every last Saturday of the month, so be there if the Sun is up and not behind (too many) clouds!

Here are some little snippets of what were we up to:

-watching the solar flares (Nathan DiDomenico at the telescope), most probably related to the raging solar storm that hit us (the Earth) on Jan. 23 (did you feel it? there have been quite a few technical difficulties noted at the radio, as well as some internet glitches):

-the comet making: our own Julia Child (a.k.a. Anthony Saikin) is explaining how the real dirty snow balls (i.e., the real comets) and their beautiful tails can be simulated with just a little passion for cooking and, obviously, for astronomy (not to forget the liquid nitrogen though):

-in case you worried about it, we (mostly Jimmy Corcoran) did catch the Sun on our sunspotter, with and without clouds:

-our new addition to the group, Jonathan Iredell, oversaw the asteroid experiments:

New Planetarium Shows, Public Star Parties and the End of the World!?

With the start of a new semester already in full swing, there is a lot going on that John C. Wells Planetarium this semester! This month the 2:30pm family show is "Legends of the Sky: Orion", while the the 3:30pm feature show is "Stars of the Pharaohs". Following each show, a live star talk featuring the Harrisonburg night sky will be presented. Both shows are FREE with seats available on a first-come, first-seated basis! You can find our full schedule of shows that will be presented this semester at the Planetarium website.

A brand new initiative we are launching this semester is monthly star parties at Astronomy Park, located in the meadow behind the Physics & Chemistry building. The first star party will take place on Friday, January 27 starting at 7pm with subsequent public observing sessions on the last Friday of each month! Since these observing sessions are weather-dependent, the decision to proceed with observing or to postpone to Saturday (our back-up night) will be made by 4pm on each day. This decision will be published on the Planetarium website, the Planetarium facebook page and via the Planetarium twitter feed. If you have never seen Jupiter with its Galilean satellites, Saturn and its majestic rings, Mars, Venus or even the Moon through a telescope, you definitely do NOT want to miss any of these star parties!

Lastly, with calendar turning the page to 2012, no doubt you have heard of the many ridiculous doomsday scenarios circulating online and in the tabloids you see at the grocery store. All these end-of-the-world prophecies, from the Mayan calendar ending, to the Earth's magnetic field suddenly reversing polarity in 2012, are all baseless and without any scientific merit. I've written my own short "Debunking 2012 Doomsday Prophecies" which you can find at the Planetarium website.

I hope to see many of you at the Planetarium or at a star party this semester!

Clear skies!

Shanil Virani

Director, John C. Wells Planetarium

What Students Think...

With the start of the new semester, students return to the classroom eager and excited to learn! Well, ok maybe not everyone. Nevertheless, students do walk into our classroom with preconceived notions about how the world works, some of which are just wrong. A classic example is the cause of the seasons, where in survey after survey, a majority of respondents claim the cause of our seasons is the changing Sun-Earth distance (not right!). Curious to learn what my students think when they hear the word "Astronomy", I asked my Astronomy 120 (The Solar System) students to write three words on an index card. The wordle below is the result of this exercise.

Unbelievable View of Our Galaxy

What would you see if you could see at levels thousands of times more faint than the dimmest star? That's the question that astrophotographer Nick Risinger set to answer. The result, after stitching together nearly 37,500 exposures, is a 5,000 megapixel photograph of the entire sky. What dominates is our beautiful, Milky Way Galaxy, home to our Sun and our solar system.

What an incredible mosaic! Check it out: http://media.skysurvey.org/interactive360/index.html

One of Our JMU Undergrad Astronomers at NCUR 2011

At this year's National Conference for Undergraduate Research (NCUR), JMU's Physics and Astronomy research was represented by Nathan DiDomenico (a sophomore!), who presented his work on "The Spectral Properties of Galaxies with Water Maser Emission." In Nathan's own words, here are some thoughts about this event:

Last week I was in Ithaca New York for the National Conference for Undergraduate Research (NCUR) held at Ithaca College. The conference was fun and interesting. Being able to get out of class for a few days and getting to know other students who are doing research at JMU was definitely a plus. NCUR is a conference for students involved in all areas of research so I was able to see thought provoking presentations from many different fields. We left JMU Wednesday in the early morning and 8 hours later we were in Ithaca New York.

There were really two parts to the conference, the oral presentations that were held in several of the university’s lecture halls, and the poster presentations held in the school’s gym.

Both types of presentations were interesting to go to. At the poster sessions I was able to browse through a number of interesting presentations and discuss them with the student conducting that research; discussions were informal and thus provided good opportunities to get exposed to a broad sample of research conducted by students all around the nation. The oral presentations consisted in fifteen minutes talks plus five minutes after the talk set aside for questions; I think many of them were very well prepared.

I personally presented a poster, my first on the work I conducted so far on the properties of galaxies that host megamasers. Megamasers in disk configurations (in active galactic nuclei) give us the vital ability to get accurate distance measurements to very distant galaxies. Because of this, it is essential that we locate a much larger sample of these megamaser disks to constrain the Hubble constant; knowing the host properties of the galaxies that have masers is key to finding more of these megamasers disks. I have compiled optical data for the largest sample of galaxies hosting masers and classified them via their optical emission lines. I was able to present my research to a number of interested students as well as scientists who had come to the conference.

I would suggest that any wise college student adheres to the fooling creed: “work hard play hard”. The group of 11 JMU students (as well as the faculty chaperones) I went to NCUR with was no exception. When we were not presenting our research or learning of about others’ research we wasted no time in goofing around. The first night we were there we conquered the pizzas from “Northeast Pizza and Beer” (that place gives new meaning the words “large pizza”), and then to our delight discovered that it was karaoke night. We couldn’t deny the crowd the sound of our voices, so we sang a few classics (I think we had a pretty sizeable fan base before we left). In the evenings we typically agreed on a place to eat and joked with each other into the night. The group was able to bond quickly and overall everyone seemed to enjoy each other’s company; this made the trip just as entertaining as it was educational.

My bottom line: undergraduates involved in research should try not to miss the opportunity to participate to an NCUR.

-Nathan DiDomenico

Here is Nathan enthusiastically explaining his findings to a good crowd of undergraduate science sponges.... aaah, students.

In case you need more reasons to be jealous of the good time NCUR students could generally have, added here is also a little (rather poorly in quality) movie caught by one of the two faculty chaperones during one of the impressively well organized lunches.

Bad Science Movie Night Was A Success!!

This past Thursday evening (April 7), approximately 40 JMU students came out to the Planetarium in Miller Hall to watch "The Core"! The event was clearly popular and a resounding success!! Given that this was the first time such an event was held at the Planetarium, and students really didn't know what to expect, the fact that the Planetarium was effectively at capacity in terms of good seats to watch the movie on the big dome means that students are interested in science and how it is presented in pop culture.

And they didn't leave disappointed. There were no technical glitches with playing the movie, although I had minor issues at the end of the night in getting my powerpoint presentation to display on the dome. :) Nearly half of the audience remained afterwards as we debunked some of the really bad science presented. Every movie requires some suspension of disbelief, and they did get some of the science right, but seriously, where did all the rotational energy of the Core go when it stopped rotating?!?

The night was such a success that we will definitely make this a regular event in the Fall! If you have movie suggestions that you would like to see on the Dome, please email me!

A big thank you to the Dept. of Physics & Astronomy for providing funding for pizza and drinks, and in particular, to Kim Emerson for looking after all the details! The students really appreciated it!

Shanil Virani

Truly Amazing Northern Lights Video!

This Thursday, April 7, the John C. Wells Planetarium will be hosting its first "bad science" movie night when we will show "The Core" on the big dome! The movie speculates what might happen if the Earth loses its magnetic field. One of the amazing consequences of our planet's magnetic fields, are the "Northern Lights" (and the "Southern Lights"!).

We are treated to these visual displays because of charged particles (electrons, protons) that are ejected from the Sun and make their way to Earth as the solar wind. These charged particles follow the Earth's magnetic fields (think of a bar magnet!) and enter near the poles. The Sun has an activity cycle, ie times when it is more active -- more sunspots -- which can trigger larger eruptions called coronal mass ejections (CMEs). These CMEs, which can wreak havoc on our electrical grid, can sometimes produce auroral activity as far south as Louisiana but this is rare. Living in Canada, I was fortunate to witness many auroral displays.

If you've ever seen the Northern Lights, and especially if you have not, you must check out this video constructed from time-lapse photography! Ole Christian Salomonsen has spent the last 6 months, snapping nearly 50,000 photos, chasing these beautiful displays near his hometown of Tromso, Norway. Imagine seeing this on the big dome in high resolution!

Shanil Virani

In The Land Of The Northern Lights from Ole Christian Salomonsen

Happy Vernal Equinox Day!!

Otherwise known as the start of Spring.

Today at 7:21pm EDT will officially mark the end of Winter and the start of Spring in the Northern Hemisphere. In the Southern Hemisphere, the opposite is true: today marks the end of their summer and the start of their fall.

Astronomically, what does this mean?? The Earth's rotational axis is tilted by ~23.5 degrees with respect to the plane of the "ecliptic" (the apparent path the Sun takes across the sky over a year as seen from Earth). BTW it is precisely this tilt which is the cause of the seasons (NOT due to changes in distance)!! If we now imagine extending the Earth's equator out onto the night sky (the "celestial sphere"), and call this the "celestial equator", the equinoxes mark the 2 times in the year that the ecliptic and the celestial equator intersect. In March, we call this the vernal equinox, and in the fall, we call it the autumnal equinox. The consequences of this intersection are:

1) Today we will have approximately equal hours of daylight and darkness. As we get closer to summer, our hours of sunlight increases until we reach the Summer Solstice (the highest point the Sun will reach in our sky; see diagram). This pattern is symmetrical in that we will again have equal hours of daylight/darkness at the autumnal equinox.

2) On this day, the Sun rises due East and sets due West. Various cultures built structures to keep track of the Sun's motion -- really a calendar! Indeed, one of theories that attempt to explain what Stonehenge is has to do with its ability to predict the equinoxes and the solstices.

For us Northerners, the start of Spring is welcomed as it marks the beginning of warm, sunny weather full of colors as flowers blossom and trees bloom. It also tells us we survived the end of an another cold, snowy winter. For me, it reminds me of the start of the major league baseball season (Go Blue Jays!) and that beach weather is right around the corner!

To learn more, consider attending one of our public star talks at JMU's John C. Wells Planetarium! We have exciting dome shows every Saturday at 2:30 and 3:30, followed by star talks, during the school year.

Shanil Virani

Don't Miss Tomorrow's "Super Moon"!

By now, you've probably heard of various media reports touting tomorrow's "Super Moon". Why all the hype? Is it even really a "super moon"?!

The orbit of the Moon around the Earth is not a perfect circle; it is slightly elongated meaning that there are times when the Moon is closer to the Earth than it is at other times in its orbit (see this diagram). Tomorrow's full moon just happens to coincide when the Moon reaches its closest point to Earth in its orbit (termed "perigee").

What effect does this have for tomorrow's full moon? Some calculations suggest that the Moon will appear 14% bigger and 30% brighter than when the Moon is at its furthest point from Earth ("apogee"). Moreover, apparently this rare alignment of a full moon coinciding at perigee only happens every ~19 years although the last such event was just 3 years ago. It's not clear how this 19 year period was calculated. A better question to ask is will you notice a larger moon tomorrow night compared to last month's full moon or next month's full moon. Here the answer is probably no. Still, if this event gets people outside to enjoy our night sky that is slowly disappearing because of light pollution, then I think that's "mission accomplished"! So if it is a clear night tomorrow, make sure you do take a moment to step outside, look up and enjoy this celestial treat!

When you do, the bright object to the lower left of the Moon is the ringed planet Saturn! And below Saturn, will be the bright star Spica!

NOTE: Be careful of the bad science reports you may have seen online suggesting this rare alignment triggers natural disasters. This is just poor reporting by people with poor critical thinking skills. Just for example, consider the fact that the two previous "super Moon's", in March '93 and Dec '08, passed without any incident whatsoever. This full moon will bring with it "perigean tides" but these extra high tides should be nothing to worry about according to NOAA. According to their reports, lunar gravity at perigee will cause the tides to be higher by an inch or so than normal. No big deal.

Shanil Virani

A Solar 1st of March

Yesterday, on that superbly sunny 1st of March, one of the side walksof JMU's campus got the rather rare chance to host astronomy students busy at work and eager to set up some solar observations. Although no solar storm was expected and the sunspot activity was quite mild, the excitement was high for playing with JMU's Physics and Astronomy Department Coronado solar telescope (with its sheltering H-alpha filter) and a Sunspotter (the safest solar telescope human beign ever invented). The Astr221 students saw for themselves the active Sun (sunspots and flares), and attempted to present this phenomenon to as many of their JMU colleagues as would venture on the (our!) side walk during that noon hour.

The Astr 221 classmates Thomas Redpath (senior), Kyle Eskridge (sophomore), and Andrew Rowe (sophomore) estimate that they were able to explain various things about energy production in the core of the Sun or about the origin and properties of the sunspots to at least 15 students who were brave enough to spend a few minutes with us on their way to or from their classes. Senior Collin Wilson happily joined us initially for a few minutes, but as it turned out, he found it impossible to leave us alone with the Sun.

Many thanks are due to Sean Scully for his help with finding the best spot for the observations, recalling that counterweights are needed to stabilize the telescope and for finding such weights in a fashionable time. He claims to be rewarded by the sight of his colleague(Anca Constantin; the Astr221 instructor)'s crazily enthusiastic efforts to convert every single passer-by into a scientist.

Alumni Update: New Astronomy Research at JMU

Many of you may have seen me looming around the department and might know I am currently working with Dr. Anca Constantin. What have I been doing, you ask? Well, I have been doing data analysis on spectra from the Hubble Space Telescope (HST) towards a paper on the aperture dependence of the nuclear galactic nebular line emission. This week, I will be starting on data from the Multi-Mirror Telescope. Now, that’s a good sound byte, but what does that even mean? You’ll say, “come on -- what have you really been up to? And why is it that, if you’re doing research, every time I pass by, you’re just staring at that 27-inch iMac screen?”

The project is centered on Active Galactic Nuclei (AGN). An AGN is black hole sitting in the center of a galaxy and actively accreting matter. We know these super-massive beasts must be accreting matter because we see emission lines in the spectra coming from the very central regions of galaxies, and those emission lines are consistent with matter being accelerated to relativistic speeds. Keep in mind, spectra are our only tool to probe Astronomical objects; they tell us what they’re made of, how fast they’re moving, how big they are, how far away they are – the list goes on. Those amazing emission-line spectra are what I play with all day. This would be a jump back to Physics 270 -- remember the Balmer series for the Hydrogen atom and all that? “Of course I remember the Balmer series. Pish-posh! What I want to know is, how do you play with spectra?”

Well, when I first started I downloaded a bunch of 2-D spectra from the HST archives. (Warning: begin “slight lie”) Remember that to get a spectrum, I hold a prism up to a light source and break the light into its components. So you can think of a 2-D spectrum as being “wavelength” along the x-axis, “physical horizontal distance” along the y-axis, and “flux” as the z-axis – graphed as color scale. (End “slight lie”) First, I had to extract a 1-D spectrum from the 2-D spectrum using this technical software called IRAF. IRAF is all text based, most astronomers use it, and a few months passed before I built up any kind of intuition with it. My previous computer know-how was mostly GUI-based with a few exceptions for programming (shout out to Dr. Ingham’s Matlab topics course, circa 2006). Once I have all my spectra extracted, I have to clean them.

You see, the crazy thing about space-based detectors is, you have much better resolution but you get so much space-noise. High-energy particles (alpha, electrons, etc) are flying around everywhere, zapping your detector. They show up as huge spikes on my spectrum. So to get rid of them, I take two images of the same region, overlay them, and get rid of any signal that’s not on both. I do this, again, with IRAF.

You know, it turns out IRAF will do just about anything you want it to – extract, reduce, plot, clean, cook, etc -- as long as you scream obscenities and throw enough things around the room. Luckily, I’m very good at both of these things, so my IRAF does whatever I want it to. I say jump, IRAF says “ERROR: floating point invalid operation.” …. doh.

Moving into a more recent timeline, I just spent the last week, give or take, carefully plotting fits to the extracted, cleaned, Doppler-corrected spectra. The normal emission lines I would expect to see are narrow. In other words, when I look at a graph of Flux versus Wavelength, I expect a slim peak at some wavelength that is indicative of a specific atom, ion or molecule. I spent a long time making sure I had the best fits I could obtain using 5 narrow Gaussians -- representing a doublet for singly ionized Sulfur [SII], Hydrogen-alpha [Ha], and a doublet for singly ionized Nitrogen [NII]. (This is a slight lie for brevity. I also had a 6^th, linear component that I used to fit the background from just the galaxy.) When my fits just didn’t seem to work and I felt like giving up, I introduced a broad Gaussian for [Ha]. “Wait, wait. What? You just told me that emission lines were narrow. Why would you fit a broad Gaussian to something that’s supposed to be narrow?”

It turns out that when matter is pretty close to the super-massive black hole in the center of a galaxy, it orbits at incredible speeds. This means that the narrow line I expect is actually Doppler shifted – both into the blue (coming towards me) and the red (going away from me). I still see a narrow line from Hydrogen that is further from the AGN, and as I look at Hydrogen that is closer and closer to the nucleus, I see more and more Doppler shifted lines. Of course, I see all of these “individual lines” at the same time; so add all these up and I get one big, broad “hump” where I’d normally expect a thin line. This is what I fit with the broad Gaussian component.

Let’s take a break from technical mumbo-jumbo. We’ve just reached the exciting part! The broad component is what I want; that’s where the science really starts for me! Doing analysis on the broad component is what tells me about the region closest to the black hole. I can recover the mass of the black hole and a swarm of other properties. I am probing the centers of galaxies from my lab in the JMU Physics and Chemistry building!

“… well … what do you expect to find?” If you find yourself asking that question, then my sinister plan has worked and I should tell you that Dr. Anca Constantin is actively looking for people to come join her team! You can come see her in office hours or stop by the lab and ask some questions. She has lots of other projects for people interested in Active Galactic Nuclei or other extra-galactic Astronomy research. Also, if you’re interested from that teaser, members of Dr. Constantin’s research team, including myself, will be presenting in the JMU Research Symposium that is coming up.

This is where I, foregoing transition, should say that I have been given a unique opportunity to be a paid Astronomy researcher (with a BS in Physics), paid for by NASA grant, at a University that does not have post-docs. Letting the Physics majors get a better glimpse of this position is what inspired a Blog update -- specifically because in the future, more of these opportunities might exist. This opportunity has been a great learning experience, resume builder, and an amazing preparation for graduate study. I think it would be well worthwhile for any graduating or rising seniors to keep eyes out for opportunities such as these in the future.

It's been a busy recruiting year here in Physics and Astronomy!

I am pleased to announce that Dr. Anca Constantin has agreed to join our department in July this year.

Anca earned her B. S. degree from the University of Bucharest, Romania in 1995 and her Ph. D. from Ohio University in 2004. Since then she has held a postdoctoral position at Drexel University and a fellowship at the Harvard-Smithsonian Center for Astrophysics in Cambridge, MA. Her research studies the accretion processes in the centers of galaxies. This includes the exploration of black holes at the center of galaxies and the so-called Active Galactic Nuclei. This is an exciting field of research and good complement to existing research in our department. She has been well funded by NASA and the NSF.

We are looking forward to Anca being part of our department and bringing her exciting research program to our students.

The addition of Anca brings us to a total 16 tenured/tenure-track faculty and a total of 21 full-time faculty. We're growing our department and our research opportunities for our students.

Welcome Anca!