Observing


This post was contributed by Genesis Guerra, a first year physics major at Union College. Over the Thanksgiving break she, along with three faculty and seven other students from Union College, St. Mary’s College of California, and University of Puerto Rico traveled to observe at the Arecibo Observatory.

group-union-stmarys

Faculty and Students from Union College and St. Mary’s College of California

I had an amazing experience at the Arecibo Observatory! I’ve learned so much about how astronomers observe our universe and derive important information from it. Before coming here I had no idea how to control a telescope or how to analyze a spectrum. I couldn’t tell what was a detection and what was radio interference, or how to baseline a spectrum, subtract background noise, and measure its rotational velocity and HI mass. But, I do now and, I feel very confident on the skills obtained on this research opportunity.

group-union-upr

Faculty and Students from Union College and the University of Puerto Rico

The purpose of our current observations is to observe and detect certain galaxies that weren’t originally detected by the ALFALFA survey because they had too low of an HI mass. Throughout our observing time, we performed two different types of observation. One was a regular targeted observation and the second one was a “search mode”. For regular observing, we observe using narrower frequency bands because we know the velocities and frequencies of the targets. We get better resolution from narrower bands. For search mode, we use wide bands to cover a bigger and wider range of velocities on the sky. We do this because we don’t know the velocities and frequencies of the targets.

Braving torrential downpours and the ominous tidings of a full moon on Friday the 13th, four Skidmore College students doing research with Mary Crone Odekon made their way from Saratoga Springs NY down to Union College. That night they had the opportunity to remotely control the Arecibo Observatory in Puerto Rico along with Parker Troischt from Hartwick and Becky Koopmann from Union. Observations are currently underway as they look for HI detections from galaxies with detected star formation.

remoteobs13jun2014c

Margot, Parker, and Yang.

So far, this summer’s work for the Skidmore group has involved confirming previously obtained group selection results from the AGC catalog with the Sloan Survey data. Happily enough the two data sets resulted in the same group identifications and further work is now underway to improve the determination of local density for each galaxy deemed to be a member of the group. The new technique being implemented relies on an absolute magnitude selection after employing the previously implemented red shift cut on the entire survey data set. The goal is to be able to compare the local density for groups at different distances.

remoteobs13jun2014b

Skye, Pierre-Francois, and Yang examine a possible detection.

Another aspect of their research has involved checking the uncertainties in HI mass and HI deficiency that arise from uncertainties in galaxy distances. This was accomplished using a random number generator to create iterations with distance errors with a gaussian distribution that has a standard deviation of 10% of the galaxy distance. Analysis of the original data and the randomized sets have thus far shown that the estimates of HI mass and HI deficiency statistics are robust.

Finally, they are checking whether their results depend on whether galaxy groups are defined within a fixed radius or depend on the size of the groups. So far the results look similar even when groups are defined in this different way.

The galaxies they are trying to observe right now are elusive in HI… They keep being non-detections! Where is the gas coming from to create stars??? (Wormholes??)

remoteobs13jun2014a

Yang, Becky, Margot, Pierre-Francois, and Mary.

Jeff Miller here, one of the two astronomers from St. Lawrence University. I’m here with my SLU colleague Aileen O’Donoghue and a group of faculty and students from Union and UPR who are observing during the week of Thanksgiving. Becky Koopmann once again serves as our fearless leader (although why she puts up with me, I’ll never know). There’s nothing better than leaving the cold, icy weather of northern New York behind to bask in the sunshine and radio waves streaming towards Arecibo!

Aileen and I are enjoying our first night of observing, and things are going very well. There was a slight break in the observing while technicians investigated a strange noise in the dome. Fortunately, it turned out that nothing was found, and observing resumed. We’ve had many detections tonight, and consumed many salty snacks. One of the more exciting detections was a “dark” source that Martha suspects is an OH megamaser. A very exciting observation, indeed! We’re here for two more nights before the crew from St. Mary’s arrives, so we’re looking forward to more exciting discoveries.

Miller-ODonoghue

SLU astronomers Jeffrey Miller & Aileen O’Donoghue

Observing-night3

Observing on the third night: Jeff Miller (SLU) and UPR students Jorge Padial, Jonathan Perez and Andres Arrieta

This post was contributed by Jonathan Perez, a student at the University of Puerto Rico, who participated in the observing run in March 2013 after attending the UAT workshop at Arecibo in January 2013.

To only say that the experience at the Arecibo Observatory was unique does not reflect in its entirely the true nature of this opportunity. I guess if I had to say what was one of the most significant details of the experience, it would have to be the comprehensive insight that one receives of what a scientific research career would be like. Radio astronomy wise speaking, this experience opens your eyes of how it all goes down, meaning that one can see how all the raw data is receive, collected, analyze and then stored for a later more comprehensive and thorough review. However, I must say that the most awesome moment (which is almost always the little details) was the opportunity to look into the clear night sky next to the world’s biggest radio telescope; giving away a sense of its endless wonders, and the urge to understand its mysteries.

Jonathan (left) and other members of the UAT on the tour of the telescope. The Arecibo telescope is amazing!

Jonathan (left) and other members of the UAT on the tour of the telescope. The Arecibo telescope is amazing!

This post was written by Andrés Arrieta, a student at the University of Puerto Rico at Rio Piedras during his first observing experience as a member of the Undergraduate ALFALFA team.

The excitement I felt as I arrived to the Arecibo Observatory was belittled by the growing excitement that I would come to feel with every minute that I spent learning, conversing and investigating the universe throughout the weekend. Every person I met had something beautiful to teach me in all aspects, not only astronomy. I learned about the process of identifying galaxies by interpreting the data produced by the telescope. Also, I learned about the process by which the telescope gathers that data, which involves a period in which it is on source and then a period in which it is off source, which will be subtracted to produce a final result. After this process, one interprets this information and decides whether there is enough evidence to say that the source is a galaxy (also using the SDSS optical information as an aid in our identifications). Overall, it was a great experience; everyone I met during my stay was nice and very willing to answer questions and have enthralling conversations about diverse topics. It is was wonderful to be given the opportunity to spend a weekend doing something I love and getting to know people that fuel the love for science with their presence and knowledge. I cannot wait to do it again!

Jonathan Perez (UPR), Andres Arrieta (UPR) and  Joseph Serrano (UMET) listen to Parker Troischt (Hartwick Coll) explain how the observing program is designed and scheduled.

Jonathan Perez (UPR), Andres Arrieta (UPR) and Joseph Serrano (UMET) listen to Parker Troischt (Hartwick Coll) explain what the observations are revealing

I’ve been at Kitt Peak (along with Mike Jones) for the past several days doing optical follow-up on ALFALFA HI detections. Specifically,we’re searching for stellar counterparts to potential nearby gas-rich low mass galaxies. I’ll write more about the science at some point in the future, but for now I want to focus on the observing we’re doing.

Image

The WIYN telescope looking up through the dome slit. (Photo courtesy Mike Jones.)

We’ve been using pODI on the WIYN 3.5m telescope. ODI stands for One Degree Imager, and pODI is the partially filled ODI – rather than a one degree field of view it has a ~24′ field of view, with a few outlying chips sampling the full field of view. The instrument is still being commissioned, meaning it is offered as “shared-risk” observing. This is pretty common for new instruments. Not only does it allow science observations to begin sooner, it also lets the engineering and instrument team know what needs further work and development. There’s nothing like bringing in an outside observer to break your instrument – they don’t know all the ins and outs and will naively try things that don’t work.

Image

Looking at the primary and tertiary mirrors of WIYN. (Photo courtesy Mike Jones.)

We’ve experienced some of the shared-risk with the “penalty box”. Last night we had to cycle power to the detectors two separate times because some of the controllers stopped responding. Unfortunately, every time you cycle the power you have to wait an hour for the system to become stable. Any data you take during that time can’t be calibrated, so you end up twiddling your thumbs a bit. Following the observer previous to me, I’ve been referring to this waiting time as being in the “penalty box”.

There are other aspects that go along with using an instrument that is being commissioned. For example, not all of the control software is complete yet. We have everything we need to run the telescope, but not everything is integrated fully so we have lots of windows open. Some of the windows also have a few quirks that can be confusing, but we’ve developed a routine and it seems to be working well.

Image

All our monitors and windows. (Photo courtesy Mike Jones.)

While there are always issues that go along with using a brand new instrument, it’s also super exciting. And new instruments bring new capabilities.

Last night (12.10.25 in ALFALFA nomenclature), we completed the ALFALFA drift scan survey, known as Arecibo observing program A2010. Riccardo and Martha conducted the observations from the “Camuy Cave” on the 5th floor of the Space Sciences Building at Cornell. It’s a little hard to believe that we’ve actually done it!

The last telescope schedule showing program A2010, the ALFALFA drift scan survey

It was a memorable night. Even before we began, the awesome Undergraduate ALFALFA team sent us a e-card. Thanks to you all! We look forward to the continuing activities of the UAT!

Riccardo reads a printed version of the UAT e-card. Notice the smile on his face!

Some friends came to celebrate the end of the A2010 era. Martha had on her ALFALFA t-shirt (thanks of course to the UAT) so it was all very official.

Bonnie, Martha and Jim celebrate the moment. As should be clear, Martha was having “more fun than human beings should be allowed to have” (ALFALFA motto #2).

Of course, it is not just all about observing, and with the end of the drift scan program A2010, ALFALFA is not really done yet. There is a lot of work still to do! Once ALFALFA discovers something interesting, a lot of followup work has to be done. For example, we recently discovered a fairly strong signal that turns out to be associated with a really, really, really faint (in terms of starlight) galaxy. We are now trying to determine its precise distance and star formation history using ground (WIYN, LBT, JVLA) and space based telescopes (Hubble, Spitzer). Just this one galaxy could keep us busy for a while. And there are lots of fascinating ALFALFA discoveries!

Riccardo introduces Leo P, a tiny nearby galaxy discovered by ALFALFA, to Anita, Don and Luke.

ALFALFA couldn’t have happened without the participation of the ALFALFA team of all ages and career stages and the support of the dedicated and expert staff of the Arecibo Observatory and the National Astronomy and Ionosphere Center. The survey has been carried out on a low budget with no dedicated full-time staff. So, to all of the people who have participated in one way or another, we thank you – each and every one!

The observing on this last night went swimmingly and, as usual, there wasn’t much actually to do except to monitor the data taking. So there was a little celebration…. Thanks especially to Carlo (BB) for the bottle, Ron (and the UAT) for the culatello and parmigiano, and Edy and Marcia (4F Club) for the chocolates.

Luke, Greg and Mike (rear) keep an eye on the observing while Martha and Riccardo celebrate the end of A2010. As to the observing, it was a boring night, but as we all know: “Boring is good!” (ALFALFA motto #1)

We also note that those 4,741.5 hours do not include all the time spent planning, archiving, flagging, signal extracting, etc, etc, etc… And just because A2010 is done, that doesn’t mean ALFALFA is finished. We still have to “bring in the harvest”!

Next Page »