Coming down a mountain should be easier than going up, but not this time. The storm that assaulted the Roque de los Muchachos mountain top observatories, has rendered any observations impossible through the 10.4 meter GTC telescope. It also has triggered several rock slides along the narrow two-lane road that snakes its way up the side of the ancient volcano. Enormous boulders have completely closed off the road back to Santa Cruz de la Palma.


Two nights of heavy rain and and high winds have further delayed commissioning of the CanariCam. Everything has checked out so far, including the complicated software interfaces with the observatory’s system. All that is need are a few nights of clear skies so that the infrared camera’s performance can be verified. Then it can begin looking deeper into active galactic nuclei hiding supermassive black holes, and debris orbiting young stars in the process of forming their own planetary systems. Today, September 25, it looks like the skies are finally clearing over the island of La Palma.

CanariCam’s intricate optics and electronics are housed within a hexagonal black structure able to withstand the extreme pressure caused by the fact that, although its interior is at a near vacuum, 14.7 pounds per square inch of atmosphere is pressing in.

CanariCam in lab before installation

The interior is also maintained at a temperature of 8-10 Kelvin, just 14.4 degrees Fahrenheit above “absolute zero.” For this reason, astronomers often refer to the camera structure as the “dewar,” a device used for containing and maintaining extremely cold temperatures (essentially a very large and very efficient thermos).

Depending on the mode being used during infrared observations, the optical path from the main telescope may pass through a spectrograph, splitting the electromagnetic radiation and allowing examination of individual spectral lines created by the presence of different elements.

In the polarimetric mode, however, CanariCam can also detect the orientation of radiation that has been polarized through various physical processes. UF astronomer Jonathan Tan, for example, hopes to examine very young stars in the Orion Nebula (M42), a stellar nursery about 1350 light years from us. The stars which have just formed from a collapsing cloud of dust and gas are obscured in visible light by considerable dust, but CanariCam can pierce through and afford a better look. By seeing the actual orientation of this dust caused by enormous magnetic fields, we may be able to better understand the way in which stars and their associated protoplanetary disks form and develop over time.

Uf Astonomer Chris Packham adjusting polarimetric filter for CanariCam installation

CanariCam also has a coronagraph, which basically allows an obscuring disk to be placed in the optical path, allowing the high radiation from bright objects such as stars to be physically blocked out and prevented from overwhelming the fainter surrounding details. The coronagraphic and polarimetric capabilities of CanariCam are unique among the world's mid-infrared instruments.

Many projects are vying for time on CanariCam. Once the camera is successfully commissioned, the largest single telescope in the world will have a new window on the universe. The University of Florida instrument will be only the second one commissioned for this incredible telescope, explaining the keen interest and commitment of the observatory staff to help out every step of the way.

CanariCam installed at focus, with 42 inch GTC secondary mirror assembly visible in upper background

Meanwhile, a lot closer to home, due to the rock slides it is impossible to drive up or down the mountain without a relay of vehicles to assist. I hitched a ride part way down with some astronomers from Durham University in Northern England, who are working on experiments in adaptive optics with another telescope, This technique attempts to eliminate the effects of turbulence in the atmosphere by making minute observations of its effects and adjusting the shape of the telescope mirror in real time to compensate for such fluctuations.

Astronomy is a cooperative international endeavor. Through its partnership with the GTC and through its design and construction of instruments such as Professor Charles Telesco's CanariCam, and Professor Steve Eikenberry's FLAMINGOS-2 (a near-infrared wide field imager with multi-object spectrographic capabilities, installed at Gemini South Observatory, Chile), the University of Florida stands shoulder to shoulder with astronomers from around the world, putting Gators at the forefront of new scientific discoveries.

These blogs were written by Terry Smiljanich, a member of the Advisory Council of the UF Department of Astronomy, and will continue next week with updates on the continued commissioning and performance of CanariCam.

September 22, 2010
GTC Observatory
Roque de los Muchachos
La Palma, Canary Islands

All dressed up and no place to go! CanariCam, the University of Florida’s new high tech mid-infrared camera, is hooked up to the spectacular 10.4 meter (410 inch) GTC telescope, passing all of its commissioning tests so far with flying colors, and ready to start bringing in new astronomical data from deep space. But closer to home, a strong front has moved in and the mountaintop is covered in clouds, rain cascading off of the closed up dome, while the telescope sits idle, safely within its custom made garage.

The storm is bad enough that local authorities have activated emergency plans due to heavy rain and winds. On the mountain, movement is restricted between the astronomers' dormitory and the telescopes. If the weather continues to deteriorate, there is a possibility that the GTC telescope operator might decide to temporarily abandon the telescope. Here at the GTC, all is quiet and uncommonly empty as the rain continues to fall. Oh well, no scientific data today.



Into the early morning hours, the team has been checking out the workings of the University of Florida's CanariCam, designed and constructed by Professor Charlie Telesco and his team. They are making sure that it is properly aligned with the telescope, is communicating with the control room scientists, and is receiving images as expected. Until it clears up, however, the only “objects“ it can image are a couple of astronomers on the catwalk of the dome. The man on the right is doing the Gator chomp, imaged at mid-infrared!



Once the weather clears (maybe by Friday), the team can point to a few bright stars, check the pupil alignment, make sure the guiding of the telescope is working with the camera, and finish full commissioning of CanariCam. Then the real working science can begin.


Charles Telesco, Principal Investigator on CanariCam

Because the instrument must be able to pick out the relatively few photons from a distant protoplanetary disk or galactic nucleus, mixed in with millions of extraneous photons from the background radiation, the atmosphere, and the telescope itself, it is necessary to use a few astronomical tricks such as “chopping and nodding.”

Chopping is the process of offsetting the imaging by a tiny amount. Because the background radiation stays relatively the same for each offset image, they can be subtracted from the final image to eliminate the unwanted radiation from the final data. These offsets can be as small as 10 arc seconds (trust me, that’s a very tiny amount) every 5 seconds.

Nodding is the additional process of moving the telescope to a new nearby position once or twice a minute. This further refines the final image across the field of view, helping to eliminate the heat of the telescope itself. The combination of techniques allows CanariCam to detect faint objects with as little as a couple of minutes of exposure, and draw out the fine details that will reveal more knowledge of our universe.



All of this, of course, depends on the proper functioning of the telescope itself. A tour of the observatory with Chief of Operations Michiel van der Hoeven, originally from the Netherlands, reveals just how complicated this can be.


Michiel van der Hoeven, Chief of Operations, GTC

He explains that ventilation of the dome is critical. As any amateur astronomer can tell you, it does no good to have a large telescope and a clear night if your lenses are dripping with dew from the moist outdoor air. Also, air turbulence inside the huge dome can deteriorate the telescope’s performance.

An entire intricate system of cooling units (twenty large air conditioners), vents, and windows keep the interior of the dome cool and balanced so that when the dome is opened, the mirrors are at the proper temperature.

Moving a 400 ton telescope poses its own problems, but the GTC has that task well in hand. The entire telescope rests on hydrostatic bearings - not steel bearings, but rather a very thin layer of pressurized oil, which minutely lifts the telescope and allows it to glide with almost no friction. A child pushing against the telescope’s frame can move the entire assembly, giving a few visiting children bragging rights. “I moved a 400 ton telescope with my bare hands."


Closeup of bottom edge of telescope dome resting on pressurized oil, the overflow dripping into a pan

Although the GTC is functioning and busy with astronomical projects, aspects of its operation are still being worked on. The large ventilating windows on the dome, which will allow the flow of outdoor air to keep the telescope cool, are not fully operational as yet. Also, the dome doors do not fully open, limiting the telescope to a maximum elevation of about 70 degrees, plenty for important work but not yet 100%.

The 36 segmented mirrors are each separately controlled by motors mounted on their backsides. These allow fine adjustments to be made to their surfaces, sometimes as small as 2 nanometers (one billionth of an inch!), making sure the mirrors are in fact working as one large almost perfect mirror surface.


View of the rear of a spare segmented mirror

Alien asteroid belts and the secrets of our Milky Way's center must wait, however, as the rain continues to beat against the windows of the control room. Twenty astronomers and observatory staff were crowded in here just a few days ago, but now it contains only team member Frank Varosi, continually massaging the software interfaces and controls, a lone telescope operator, and me - an amateur astronomer having the experience of a lifetime.


Frank Varosi, Senior Software Engineer



Terry Smiljanich

"CanariCam Is In 'Da House"

Early in the morning, the control room of the Grantecan 10.4 meter telescope is filling up with excited observatory staff and astronomers. Michiel van der Hoeven, Chief of Operations at the world's largest telescope, convenes a meeting of 17 staff members plus the six members of the University of Florida team, to plan the complicated logistics of getting the CanariCam instrument and its associated electronic hardware from the laboratory up to the Nasmyth focus of the telescope. He has written "CanariCam is in 'da house!" on the message board.



Since the camera will be unhooked from its cooling unit during the transfer (and thus lose ground on maintaining a cold interior), it is imperative that the move be made as seamlessly as possible. Teams are assigned so that this can be accomplished in two hours, the length of time it took to do this last November when the camera was temporarily installed on Grantecan during "first light." "O.K.," Michiel announces, "let's rock and roll then."



A multitude of hoses, cables, interfaces, and connectors are disengaged from the camera and its cabinets, and everything is wheeled from the lab to the freight elevator to be lifted up to the telescope floor. Once there, a crane lifts CanariCam up to the platform where the telescope focus is located, and carefully bolted to the adaptor plate. Then the frame holding the electronic cabinets is hoisted and wrapped around the camera unit.





Now everything has to be reconnected, but the several staffers and Florida team quickly get matters in order, and the comforting thump of the coolhead can be heard, bringing the critical temperatures back down. One and a half hours - better than last time and a tribute to the efficiency of the Grantecan staff and the expertise of Greg Bennett, Florida's team engineer. Everyone is gratified that the camera has been successfully attached to Grantecan with minimal problems.



Watching this large group of men and women struggling to get everything performed to perfection, one is struck with awe at the fact that they are all working together, not to find more efficient killing machines or better ways of polluting our planet, but rather for the cause of pure science, expanding our knowledge of the universe we live in.

After lunch, a further group meeting plans the important task of making sure that CanariCam is perfectly aligned with the telescopic optics. This means opening the dome and moving the huge telescope during the afternoon.

In the control room, UF team members Frank Varosi and Chris Packham monitor the images coming in from the camera to evaluate the needed corrections, and communicate their findings to Charlie Telesco and Greg Bennett up at the telescope, who are making fine adjustments in the position of the camera housing at the telescope's focus.



When you are dealing with the need for sub-arc second accuracy in finding and capturing a few photons that have traveled thousands, millions and even billions of light years, you can appreciate how delicate such adjustments can get.

With the dome open during the day, and the telescope moving silently and smoothly into position, the sheer massiveness of the 10.4 meter telescope, together with its perfect balance in its mounting, can truly be appreciated.

CanariCam rests comfortably in its cradle, waiting for commissioning checkouts and a suitable target to demonstrate its powerful capabilities. Charlie Telesco and graduate student Dan Li proudly hang up a Gator banner in the control room, reminding everyone that the University of Florida is not just a 5% partner in the telescope, but also the creator of one of the first important astronomical instruments that will be used on Grantecan.



Terry Smiljanich

Getting CanariCam Ready, Day Four

GTC Observatory
Roque de los Muchachos
La Palma, Canary Islands

Overnight, the hard working compressor finally got the temperature of the infrared detector down to where it needs to be, about 444 degrees below zero. A meeting is held in the morning with the observatory staff to coordinate the many activities that need to occur, some simultaneously, to get CanariCam ready for use on the GTC (Grantecan) telescope. Michiel van der Hoeven, Chief of Operations at the observatory, tells us that the staff stands ready to help get the instrument commissioned.



Now a new enemy is raising its ugly head - bad weather, the bane of every astronomer's existence. A storm is predicted to come through Wednesday, just when it is hoped that the University of Florida team can begin making initial observations. Nothing to do about that but wait and see. Astronomers tell stories of waiting months to get one precious night on a large telescope for a project, only to have that be the one night when it decides to rain, ruining the observations and requiring another multi-month wait for another try.

The observatory staff is already putting on the adaptor plate on the telescope, which will allow CanariCam to be fitted to the telescope's focus. The thick black steel plate, specially designed for CanariCam, weighs over a ton and takes three workers and a crane to get it up to the focus and bolted to the telescope. The segmented mirror (36 separate mirrors), largest in the world, sits on its side in the dome, waiting to be let loose on the skies.



In a room under the dome, six extra mirrors are kept in storage, ready to act as replacements as needed. UF astronomer Chris Packham gives us an up close look at these individual mirrors. Their undersides are covered with intricate motors and pulleys which can slightly bend the shapes of the mirror surfaces, compensating for minor errors and seeing conditions.



Suddenly, at about 12:30, the steady drone of the compressor ceases and everything gets strangely quiet in the lab. The compressor has quit working and the internal temperatures are starting to climb back up. Everyone stops what they're doing, and an intense session of troubleshooting begins. Gregg Bennett, the team engineer, takes the cover off. The compressor tank has overheated. A short? A bad solenoid switch? A helium leak? A replacement compressor is wheeled in, but the detector temperature is already back up to minus 425 degrees F, extremely cold but much too hot for infrared work. A few tweaks later and the old compressor kicks back on. The temperature immediately drops back down to comfortable levels.



Except for the activities of the CanariCam team and staff, the cavernous dome is empty and quiet. One floor below, the control room mainly consists of a maze of computer screens. Here, the dome can be opened and rotated, and the telescope pointed with extreme accuracy. Some of the more precise guiding aspects of the telescope are still being modified, but it is hoped that both the telescope and CanariCam will soon demonstrate that they make a fine pair. That is, if the weather holds up!

Terry Smiljanich

CanariCam Cooldown, Day Three

Roque de los Muchachos Observatory
La Palma, Canary Islands

Minus 340 degrees Fahrenheit and counting. The cryogenic pump has been working for over 55 hours hours now as the temperatures inside CanariCam slowly decline to optimal levels (10K or less at the critical detector and we’re OK). Meanwhile, the vacuum inside CanariCam is being maintained at levels equal to about one ten billionth of the air pressure at sea level.

Observatory staffers ask how it’s coming, as everyone is anticipating mating the CanariCam mid-infrared camera with the 10.4 meter Grantecan telescope. With the gathering power of the huge mirror (composed of 36 separate mirrors all working together as one large mirror), and the sensitivity of the University of Florida instrument, new astronomical discoveries are potentially around the corner.

There is a small “window” in our atmosphere at 10 microns (infrared wavelengths one hundredth of a millimeter in length) where electromagnetic radiation can pierce through the water vapor that blocks most of the infrared. CanariCam’s detector can observe through this window, and with the power of Grantecan will hopefully be able to achieve an angular resolution of up to 0.20 arc seconds. For us non-astronomers, that’s equivalent to being able to see the width of a human hair held 500 feet away). It is thus possible that with CanariCam we may better understand how planetary systems such as our own solar system develop over time.

Perhaps CanariCam will resolve the debris disk surrounding a faint planetary system with sufficient detail to determine whether it includes an asteroid belt similar to our own. If so, we can better understand planetary systems as a whole, rather than just the individual planets that are being discovered on a monthly basis.

This is just one of many projects proposed for CanariCam once it is commissioned. Another proposal, by UF astronomer Jonathan Tan, wants to look at very young stars buried in the dust of the Orion Nebula. CanariCam has unique polarimetric capabilities, allowing an observer to sort out the distribution of magnetic fields as they create polarization in dust particles surrounding a star. With this new tool, the development of protoplanetary disks over time can begin to be mapped out and compared to theoretical predictions.

All of this is a part of the busy astronomical activity going on at the top of this mountain. Practically next door, the 4.2 meter (163 inches) William Herschel Telescope, built in 1987, was at one time the third largest telescope in the world, before being eclipsed by the new generation of 8-10 meter telescopes like Gemini, Keck, and Grantecan. The Herschel was the first to provide evidence of a supermassive black hole, called Sagittarius A, at the center of our own Milky Way galaxy. The Deputy PI on CanariCam, University of Florida's Chris Packham (Charlie Telesco is the Principal Investigator, as Chris hastens to add), once worked with the Herschel, and proudly gave us a tour of this venerable telescope.



The MAGIC I & II instrument, just down slope from Grantecan, consists of twin 17 meter segmented mirrors pointed horizontally and looking for lingering evidence of gamma rays striking the atmosphere that came from supernovae and accretion disks around supermassive black holes. These black holes, from which no light can escape, have incredible masses, from 4 million suns to billions of suns, all crammed within very small spaces very far away. They remain invisible, but the havoc created by their interaction with surrounding matter creates super-energetic rays that can be detected. This June MAGIC detected cosmic rays from a quasar 6 billion light years away. When these rays left their source, our own Sun had not even been born yet).

All the CanariCam team can do today, a quiet Sunday with clear blue skies, is wait and watch the slopes of the cooling curves. Once the proper temperatures are reached, however, organized chaos will descend as everyone runs through final checks and the large instrument is lifted up to the observing platform and the telescope silently moves toward a distant target. You can already sense the excitement that will run high in the control room adjacent to the telescope when that happens.

Terry Smiljanich

At the Gran Telescopio Canarias, Day Two

With a few clouds drifting through the collection of white domes at the top of the Roque de los Muchachos peak, we drive up to the Grantecan to see how the cooldown is progressing. Working our way through some tourists visiting the world’s largest telescope, we head for the laboratory, where all through the night the refrigerant pump has been using helium to bring the internal temperature of the CanariCam infrared detector closer to the working target of approximately 8K.

The temperature detectors, monitored through software designed by team member Frank Varosi, show the steady progress of cooling down. The detectors are currently showing temperatures as low as 40K (-388 degrees Fahrenheit), slowly dropping after 25 hours of pumping.

Cold yes, but not nearly cold enough to allow the detector to find and count the few feeble photons making their way to Earth from cold debris surrounding a star 63 light years away, or sneaking through dust surrounding the center of our own Milky Way some 26,000 light years distant. Greg Bennett, the team engineer, adjusts a relief valve, watching the pressure readings, and the pump quietly whines away as the temperature slowly creeps downward.



The air is cool and dry at 7900 feet. Spectacular sunsets are routine here above the clouds. Due to its location, this peak is one of two premier observing sites in the Northern Hemisphere (the other being Mauna Kea in the Hawaiian Islands). The island, La Palma, is the most northeasterly of the Canary Islands, just a few hundred miles from the Moroccan coast of Africa.

The peak, called Roque de los Muchachos, is named after an outcropping of volcanic rocks looking somewhat like tall humans. It perches on the very rim of a huge caldera formed from the collapse of the Taburiente volcano a half million years ago. The caldera is six miles across and almost as deep as the Grand Canyon. From the top, at sunset one can see the shadow of the mountain cast across the Atlantic Ocean, with the island of Tenerife clearly visible.

It is here that the European Northern Observatory operates thirteen world class telescopes, with teams from Great Britain, Italy, Spain, the United States, and other countries, all working on scientific projects to explore the farthest reaches of space and time. In addition to Grantecan, other famous telescopes abound, such as the William Herschel Telescope (4.2 meters), the TNG (Galileo), and “MAGIC,” a twin set of huge 56 foot mirrors pointed horizontally and looking for particle showers caused by cosmic rays.



The University of Florida is a 5% partner in the Grantecan telescope, inaugurated in 2009, and is designing and utilizing instruments such as CanariCam for use on the facility. In return, the Florida team has access to the telescope for its own projects. Because the target is to commission CanariCam on the telescope next week at the Nasmyth focus (one of the observing spots on the telescope), the Florida team has exclusive access to the telescope for a few nights, both to commission the instrument and begin collecting important scientific data. One can detect the envy in the voices of other astronomers during mealtime discussions. “Ah, you're on the Florida team. You have the Nasmyth focus next week!”

CanariCam Commisioning at the GTC

September 18, 2010, La Palma, Canary Islands

An ocean away, on top of a tall mountain overlooking the Atlantic and the clouds far below, we finally arrive at the world’s largest telescope, the Gran Telescopio Canarias (Grantecan). The University of Florida team, led by Professor Charles Telesco, is here to officially commission its new mid-infrared camera, the CanariCam, specially designed to work in conjunction with Grantecan to explore regions of space normally inaccessible to visible light.

Internationally known for its expertise in designing, building and using high end astronomical instrumentation on some of the world’s largest telescopes, the University of Florida will install CanariCam on the business end of the 500 ton telescope facility, which uses a segmented mirror 34 feet across (over twice as large as the iconic Mt. Palomar 200 inch telescope in California). With what amounts to the largest eye on the planet, the heat sensitive CanariCam will be able to peer through obscuring interstellar dust with unprecedented accuracy, looking, for example, at the center of galaxies hiding black holes, or looking for exoplanets (planets outside our own solar system) in the process of forming around young stars.

First,however,the complicated instrument, as large as a coffee table, and hooked to closet-sized electronic cabinets, has to be checked out to make sure it is ready for installation and use. And that can get hairy. In order, for example, for the camera to detect the extremely faint emissions from distant heat sources, it has to eliminate as much as possible the heat being generated closer to home, the camera housing itself and the very telescope it is using. In addition, it has to peer through the heavy humid atmosphere of Earth.

In order to accomplish this, the infrared detector at the heart of the camera must be cooled to around 8 Kelvin (that’s -445 degrees Fahrenheit). But the new two stage cryogenic “coldhead,” which allows it to achieve such frigid temperatures, is giving the team fits. Switching back to an older coldhead unit, everyone is anxiously watching the monitors as the slow process of cooldown is underway. The laborious process should be completed by Sunday, at which time the instrument can be checked out and, if everything goes well, readied for installation on the telescope.

Astronomers from around the world are waiting, their proposals for using the unique instrument dependent upon a successful commissioning. These proposals include new examinations of protoplanetary and debris disks around young stars (potentially letting us observe the formation of new planetary systems), and penetrating the interior of active galactic nuclei, obscured by dust in the visible spectrum.

For an amateur astronomer like me, living temporarily in an astronomical community and working in a laboratory sitting beneath such a magnificent telescope, I keep waiting for someone to wake me up. “What are you doing here?” I hope to document this exciting activity in pictures and in this blog, hopefully giving a sense of being amidst science at the cutting edge. Each day for the next week I will post observations and photos, following the progress of the Florida team, explaining infrared astronomy in further detail, and looking more closely at the capabilities of CanariCam.

Terry Smiljanich

Rosemary Reborn: Students Upgrade the 30" Telescope at Rosemary Hill Observatory

Phase 1 of a student-led project to upgrade the instrument package on the 30-inch Rosemary Hill Observatory telescope is nearly completed.

Led by a Sigma Xi Grant In Aid of Research awarded to UF graduate student Scott Fleming, and working alongside Dr. Francisco Reyes, Amanda Townsend, Dr. Anthony Gonzalez, Dr. John Oliver, Robert Morehead, Nathan De Lee and Dr. Eric Ford, a new SBIG ST8X-ME CCD, a new 10-filter filter wheel, and a new set of Johnson-Cousins filters has been successfully installed.

The ST8X-ME also includes a second built-in detector that allows the CCD to auto-guide itself, maintaining image position and allowing for long integrations and stable sequences of multiple exposures. The new CCD has a significantly larger field of view compared to the previous camera, 15.6 x 10.4 arcminutes. The new camera will be used by undergraduate students to conduct research projects as part of the Observational Techniques class this semester. It will also be used by graduate students and professors to conduct research projects locally.

The attached image is a "first light", three-color image of the M13 globular cluster, observed by Dr. Reyes and Amanda Townsend, and created by Amanda Townsend. No calibration data was taken for this first light image, which is the reason for the noisier-than-usual background.

The quality of this rough image is a sign of great things to come from the new 30-inch instrument package. Better images taken with a full set of calibration data and processing will be shared in the near future after some additional tests are done with the instruments this month.