The Sun is approaching the active portion of its 11-year cycle, so visitors these days are now more likely to catch a glimpse of an interesting feature on the surface of the Sun.  Many visitors have been able to observe dark sunspot groups in our white light telescope, or spy an interesting prominence in the sun’s atmosphere through the telescope equipped with a hydrogen alpha filter.  However, the sunspots eventually move out of view and the prominences stop being quite so, well, prominent.

Luckily, there is a way to preserve these fleeting features so that all visitors will get a chance to see them regardless of how the sun chooses to behave that day. We have started taking pictures of the Sun’s interesting features through our different telescopes.  Here are those images for your viewing pleasure!

Here is an image of the Sun that was taken right here at the Museum on February 18^th. In order to capture this image, we used a camera attached to our hydrogen alpha telescope. This telescope reveals the Sun’s chromosphere, filtering out all light except the red light given off by excited hydrogen atoms.  This image shows the two large prominences that appeared on the Sun that day. You can also see some surface texture on the Sun, which is called granulation. If you were to look through our hydrogen alpha telescope, this is pretty much exactly what you’d be able to see!

We took pictures later on in the day to see how the prominence changed, and could take pictures the next day as well. Over time, this loop prominence became twisted before disappearing from our view.

We took this picture of the Sun’s chromosphere with our Calcium-K telescope on March 4^th. The Calcium K telescope filters out all but the purple light coming from excited Calcium atoms in the Sun’s atmosphere. You might notice a few brighter spots on the Sun’s surface, especially near the top right. These are hotter areas on the Sun called plages (pronounced like you’re saying “blah” except with a p).

We took this image of a super-prominence in the chromosphere of the Sun using our hydrogen-alpha telescope on March 17^th.  This prominence is truly gigantic; it’s about 5 earths tall 22 earths long!

While these pictures are pretty great, nothing quite compares to seeing the sun live through a telescope. It’s always exciting to see what the Sun is up to on any given day. We’re outside the Museum every sunny day except for Monday between 12:30 p.m. and 2 p.m., so stop by and catch a few rays!

Erin Braswell is an Astronomy Educator at the National Air and Space Museum

The Public Observatory Project (POP) is nearer to completion.  We are in the process of installing a large professional Boller & Chivens telescope in a 22-foot dome that will be available for four hours each day (weather permitting) to view the Sun, Moon and planets from the east terrace of the Museum. POP will be available for casual observing and for school and special interest groups. It will also be the Museum’s nerve center for the International Year of Astronomy throughout the rest of 2009 and well into 2010.

Over the past two weeks many people have devoted many many hours to making the Public Observatory Project (POP) closer to being ready for the public.  Once the rim of the foundation had been cast, Andy, Katie and John used both GPS and a simple shadow gnomon to determine the north-south alignment, marking the line on the rim of the foundation.  Then, a concrete pad was poured and leveled, followed by thick pads of Sorbothane, then a 6 x 6 foot iron plate, and finally the sole plate, tilted 3.6 degrees to the north to accommodate the latitude difference between Harvard, Massachusetts, the original home of the Boller & Chivens telescope, and Washington, D.C.  Larry and Ted continued to work on modernizing and ruggedizing the electronic relay system for the telescope, the pier was poured and trimmed, and finally, this week, assembly started.

The dome gore sections were brought to the terrace, as well as the walls, with the help of Joe Deregt, who came all the way from Australia to lead the charge.  The dome was assembled, then the walls went up.  Finally, yesterday, the 60-ton crane arrived, the pedestal was fitted to the pier base, and, by noon, the dome was lifted into place, carefully fitted by adjusting the base, and finally, after testing dome rotation (smooth!) the walls were secured to the foundation rim. At the end of the day, Frank, Stephanie, Joe and David were treated to dinner by curators from the Division of Space History!

More background on this project is provided in a previous blog post.

Dr. David DeVorkin is curator of the History of Astronomy in the Space History Division of the National Air and Space Museum.

The idea of such a celebration was born at a meeting of the International Astronomical Union. Once every three years, astronomers from all over the world meet in General Assembly.The last time was August 2006, in Prague. While some astronomers unceremoniously demoted Pluto at this meeting, others vowed to reaffirm that astronomy is for everybody, and is everywhere and anywhere you can see the sky,day or night. Some even proclaimed that they’d make it their mission to help anyone who wished to have the opportunity to peer through a telescope at a star, the Sun, Moon or a planet.

I was at that meeting,and thought it was a terrific idea. No, not demoting Pluto, but the IYA. I remember asking myself, how can The National Air and Space Museum contribute to this wonderful goal? The Washington Mall is not the best place to view the night sky, or the day sky for that matter. But it is where the people are – people of every shape, size, gender, persuasion. It’s one thing to get people to go where telescopes are, but its quite another to bring telescopes to the people. John Dobson and the San Francisco Sidewalk astronomers know that. So I took a tip from them and decided to build a public telescope on a Washington sidewalk, or as close as the Fine Arts Commission and the National Capitol Planning Commission would allow. Thus was born the Public Observatory Project at the National Air and Space Museum.

POP’s goal is to put a high-end fully professional telescope where the people are. These will be people who are not looking for a telescope to look through. No, these are the millions of people who come to Washington, to the Mall, to find themselves and their heritage. Encountering a telescope in the process, a big one in a visible white dome, one that can show you celestial sights of all sorts, will be a surprise for some, hopefully a delight to all. A modest value-added experience to what is a lifetime pilgrimage for many Americans.

This had been a dream of mine for years, before anyone spoke of the IYA. I fantasized turning any one of the many domes on the Mall into an observatory. The Capitol dome! Natural History’s rotunda! The National Gallery rotunda! Why, even the Washington Monument would make a great mounting for a gigantic aerial telescope tube or a super heliostat. Why not put a dome on the Hirshhorn, and stick a telescope inside? The Mall has its monuments. What it needs is a portal, a portal to the universe. Many years ago, George Ellery Hale had this dream. When he built the National Academy, he installed a small solar telescope in the rotunda. It’s still there. Maybe someone will clean it up and open it for the public someday But the Smithsonian can’t tell the National Academy what it should do. No, I had to work from strength.

Last spring I was invited to inspect the Oak Ridge Observatory built by Harvard in the 1930s and sustained by the Smithsonian Astrophysical Observatory since the 1980s. It’s many small and medium-sized telescopes had been modified countless times, and many of them contributed significantly to knowledge in astronomy. It was closed down in 2005, a victim of changing priorities in astronomy as the combined Harvard-Smithsonian Center for Astrophysics pursued its world-class programs in Arizona, in Hawaii, at the South Pole, and in space. I inspected the site, in Harvard, Massachusetts, just west of Concord, with Sara Schechner, curator of scientific instruments at Harvard. We found many priceless gems: Henry Draper’s 11-inch three-element Clark photographic refractor telescope from 1880, the first to be used to photograph a nebula. It was painted a flat, almost pastel red, in memory of its last observing site in Jamaica before World War I. There were three “super-Schmidt” meteor cameras, there were Metcalf astrographs from Harvard’s many observing stations, and there was the famous 61-inch Wyeth reflector, the largest astronomical telescope east of the Mississippi. All of them were closed down, rusty and dusty, neglected in their dilapidated and leaky observing chambers. But there was one telescope, a lovely blue and white Boller & Chivens 16-inch telescope from 1967, sitting in a secure dome and 100 percent intact, still operating, but without portfolio. Kept running, clean and shiny, by the observatory technician, Joe Zajac, it stood there ready to be used. All one had to do was open the dome, throw a few switches, and kick out the animals.

But for me, the stars were finally in alignment.The spirit of the IYA, a museum and observatory staff that appreciated the value of an active astronomy outreach program, and the perfect telescope to do it with, all came together. I camped out at the National Science Foundation until, late in the fall, after a peer-review process and favorable reviews by the Fine Arts Commission, the National Capitol Planning Commission and the DC Historical Commission, we were given the green light.

This was not my first experience building an observatory. But it was unlike any I encountered in the past. The process is still unfolding, and it is a journey of discovery, some frustration (it is Washington, after all), but most of all, elation and joy. I teamed up with Frank Florentine, the Museum’s tenacious project manager who brought to completion, under budget, our highly successful Explore the Universe gallery in 2001. POP is in many ways for me an extension of ETU, and as with ETU, POP’s success will depend upon capturing the hearts and minds of the talented craftsmen and engineers at the Smithsonian. Many have joined in, including Joe Zajac and Alison Doane of Harvard, Rebecca Kokinda, Steve Sumner and Andy Fernandez of SI’s OFEO team. More are joining up as the work continues, including exhibition specialists, designers, educators, security staff, special events, development and administration officials.

So here are a few images and videos from the process thus far, with captions not approved by the Exhibits Department script editor, but straight from my heart. As the process continues, we’ll add images and commentary.

——————————————–

March 10 2009 – Harvard Massachusetts

Frank, Stephanie and I spent the day with Joe Zajac removing the primary and secondary mirror cells and packing them up. We also did a preliminary inventory and inspection of the site.

Stephanie inspecting the telescope’s front end, where the secondary mirror support system is visible. The mirror system is remotely focusable, but there are additional encoders to mark the position of the mirror which may be removed.

Joe (L) and Frank (R) position the lowering system to remove the heavy mirror cell.

———————————-

March 12

Delayed one day by rain, the crane and crew arrive on the 12th and commence removing the telescope section by section.

The tube was first to be removed. It weighed less than 100 lbs after the mirror cell and secondary support system were remove. There were some difficulties figuring out how to remove the tube from the polar axis housing since the tube sat on a adjustment block. That block was totally documented.

Smooth operation – up up and away!

Next step – removing the polar axis, a very heavy, complex form that included the declination axis and all drive, set and slew mechanisms, as well as electrical connections. All had to be removed and documented.

The trickiest part of the process was loosening and then removing the dozen bolts holding the polar axis to the base. When Joe (inside the pier), got down to the last bolt it was clear there was great strain on the bolt. The strapping was then adjusted until the strain was removed allowing the bolt to be extracted easily.

And the polar axis housing floated away with no rotation or swinging.

After the removal of the base, which was straightforward, we were left with evaluating what it would take to remove the last remaining piece, the sole plate. It had by design been placed into the concrete when the telescope was installed, and also had three elbow-shaped bolts embedded to a depth of at least a foot in the concrete. There was no chance of removal without damage to the plate.

So all the components were packed up and the truck was ready to roll by 2:30 p.m. A really smooth operation.

———————————————–

March 17th at the National Air and Space Museum

All the components arrived and were moved into an empty gallery 113. Inspection began the following week. No damage or loss.

——————————————–

Week of March 20th

Site preparation actually begins on the Museum’s street level terrace, south of McDonald’s just east of the main building. Chain link fencing will allow all stages of construction to be visible to passersby on Independence Avenue, and in the restaurant.

Dr. David DeVorkin is a curator in the Space History Division of the National Air and Space Museum.