Wednesday, March 31, 2010

Guided Tours Return

It is almost April. That means that guided tours of the Hale Telescope will soon be here. Weather permitting, they should begin this weekend. Do keep in mind that we are expecting snow on Palomar tonight & Thursday. There is always a chance that the weather could intervene with the tours. I will post an update on the weather & tour status here later in the week.

One thing for sure is that it will likely be in the 30s inside the dome as the interior of the 200-inch dome is kept at nighttime temperatures (for an elevation of 5,500 feet!). Dress accordingly.

These one-hour-long tours are held on Saturdays & Sundays only during the months of April through October. Tour tickets are sold in the gift shop the day of the tour on a first-come, first-served basis. The gift shop opens at 10:00 a.m. No prior reservations are taken.

Tours are offered at 11:30 a.m., 1:00 p.m. & 2:30 p.m. Tickets are $8.00 per person for all ages. The tour is not recommended for children under six years of age. Sorry, no pets.

Tours cover the history and current scientific research of the Palomar Observatory, with a special emphasis on the 200-inch Hale Telescope. High-heeled shoes are not recommended for the tours.

Alas, there is no viewing through the Hale Telescope as a part of the tours. Even the astronomers do not look through the telescope. That isn't the way research is done.

Tuesday, March 30, 2010

What is This?

I took this photo inside the dome of the Hale Telescope earlier today.

What is it? It is the reason why Electronicers have to wear gloves. What is an electronicer? It is the Palomar name for those who work with electronics, specifically electronic instruments that are mounted on our telescopes.

The photos above show a frosty valve that has a temperature cold enough to cause frostbite - hence the need to wear gloves.

If we take a slightly wider view you can see what it connects to:

It controls the feed from a tank of liquid nitrogen. The liquid nitrogen is used to cool instruments, such as the one on the right-hand side of the photo - the Hale Telescope's Wide-field Infrared Camera (WIRC). Unlike digital cameras used at home or in your phone, our cameras need to be cooled. Liquid nitrogen, which boils at a temperature of 321 degrees below zero °F is actually a bit too cold. So inside the camera we heat things a bit to bring the electronics to the optimal temperature for this camera, WIRC.

By the way, WIRC was the instrument used to take the image for last week's Astrophoto Friday image. and it goes back into service at prime focus on Wednesday night.

Monday, March 29, 2010

Palomar History Photo of the Week - March 29, 2010

This week's Palomar Observatory History Photo of the Week was taken in the machine shops at Caltech on October 15, 1935.

It shows three people (I am not sure who they are) with a steel model of the "tube" of the Palomar 200-inch telescope. They are testing the model for its rigidity.

The tube of the 200-inch telescope is what is known as "Serrurier truss". It was known at the time of design that the steel of the telescope would bend and flex as the telescope moved. Mark Serrurier designed the truss to ensure that from any position that the telescope might be pointed the optical elements would remain on axis with each other and there would be no deflections greater than 0.01 inches.

Later, Mark Serrurier would move on to other endeavors and eventually earned a star on the Hollywood Walk of Fame.

Saturday, March 27, 2010

Neugebauer Wins Bruce Gold Medal

Congratulations to Gerry Neugebauer, former director of Palomar Observatory, for winning the 2010 C.W. Bruce Gold Medal from the Astronomical Society of the Pacific.

Dr. Neugebauer joins an exclusive list of the many top astronomers over the last century or so to have won the prize. This list includes many people who also had an association with Palomar Observatory including (but not limited to) George Ellery Hale, Walter S. Adams, Edwin P. Hubble, Walter Baade, Ira S. Bowen, Rudolph Minkowski, Horace W. Babcock, Jesse Greenstein, Allan Sandage, Olin C. Wilson, Maarten Schmidt, and Wallace Sargent.

LIght Pollution Stories & Earth Hour Tonight

The May issue of Sky & Telescope magazine has hit the mailboxes sporting a cover story on light pollution. Kelly J. Beatty gives an overview of the light pollution problem with some startling facts and possible solutions. Also, look for the opinion piece by Constance Walker where she argues that education is key to solving the problem of light pollution.

In another publication, be sure to check out my article "Dimming the Lights: Astronomy and light pollution" in the current issue of the on-line Glimpse Journal. Alas, a subscription is required to read entire thing.

Finally tonight is Earth Hour. While this is billed as an event to fight global warming, it is a great opportunity to highlight how much unnecessary light at night can be found in our cities and that the world will not devolve into chaos if some or all of it is shut off. Last year there wasn't much of a change from Palomar Mountain. This year's event takes place under a bright moon, but there may actually be larger participation in the event.

Friday, March 26, 2010

Astrophoto Friday: The Flame Nebula

The Flame Nebula, also known as NGC 2024, is a stellar nursery located about 1,500 light years from our solar system. The nebula is a region of star formation that is in the process of forming a star cluster. It is visible through small telescopes. It is located in the constellation of Orion near the star known as Alnitak, the easternmost star of Orion's Belt.

This image was captured by David Thompson then of the California Institute of Technology. He used the Palomar Observatory's 200-inch (5-meter) Hale Telescope with its Wide-field Infrared Camera (WIRC).

Monday, March 22, 2010

Dark Skies Podcast

Just a reminder that the 365 Days of Astronomy podcasts continue. Just last weekend there was a new one released by Constance Walker: Dark Skies Crusader Sheds Light on Light Pollution.

I confess that I have fallen somewhat behind on them, but many of the podcasts are quite good and if you aren't listening to them I recommend giving it a shot.

Continuing on the topic of light pollution, remember that Earth Hour is Saturday, March 27.

Palomar History Photo of the Week: March 22, 2010

This week's Palomar Observatory History Photo of the Week is another picture from the Lee A. Farnsworth collection. It is a construction photo from 1936 showing the lower structure of the building which would eventually house the 200-inch telescope.

This was one of 61 photos from this collection that were scanned last week. There are many fantastic shots still to come.

Friday, March 19, 2010

Astrophoto Friday: An Edge-on Sprial Galaxy

This week's astrophoto is a composite image on an edge-on spiral galaxy known as NGC 891. NGC 891 is located some 10 million light years away in the direction of the constellation Andromeda. It has a large dust lane that is typical of spiral galaxies.

It was obtained using the 200-inch Hale Telescope's Wide-field Infrared Camera at Palomar Observatory by Kevin Bundy formerly of the California Institute of Technology and at the 10-meter W.M. Keck Observatory's Low Resolution Imaging Spectrograph (LRIS) by Patrick Shopbell and Judy Cohen of the California Institute of Technology. Yellow colors in this composite correspond to the near-infrared image which was obtained at Palomar. The blue colors correspond to the visible light image which was obtained at Keck.

This kind of representation is useful because it demonstrates the utility of observing at many wavelengths. Because the central bulge of NGC 891 appears yellow in the composite, it is clear that the infrared does a better job penetrating the dust lane of this galaxy, which almost completely obscures the bulge in the optical image.

The Palomar image is the result of the addition of twenty separate frames taken in the Ks filter at 2.2 microns, this observation required a total exposure time of 15 minutes.

Tuesday, March 16, 2010

Space Art on Exhibit in Borrego Springs

I haven't had the chance to see it in person but there is an exhibit of space art called "dark skies, luminous space" on display in Borrego Springs now through April 4.

More information is at the link above and at the artist's site

Monday, March 15, 2010

Palomar History Photo of the Week - March 15, 2010

This week's Palomar Observatory History Photo of the Week comes from February 12, 1935. The photo, taken by Ferdinand Ellerman, shows a scene from the Optical Shop at Caltech:

The large machine in the photo is the grinding & polishing machine for the 120-inch mirror, that was ordered from the Corning Glass Works at a test mirror for the 200-inch project. The 120-inch mirror was eventually sold to the Lick Observatory where in 1959 it became the primary mirror for the Shane Reflector.

Several members of the crew of opticians can be seen in the photo, including chief optician Marcus Brown who is standing on the ladder.

In front of the machine is a group of four people. On the right of that group is Dr. Robert Millikan, the Nobel Prize winning physicist who was then president of Caltech. I don't know who the other three people are. They are described merely as being "friends" of Dr. Millikan.

Saturday, March 13, 2010

Visiting Hours Change on Monday

Starting on Monday March 15 Palomar Observatory will return to being open to the public from 9:00 a.m until 4:00 p.m. daily.

Public tours return on weekends in April. More on that soon.

Friday, March 12, 2010

Astrophoto Friday: Horsehead Nebula

This week's astrophoto is of the Horsehead Nebula. The photo was taken by Milton Humason using the 200-inch Hale Telescope the night of February 7, 1951. Look here for a wider view that gives more of the context of the region as seen with Palomar's 48-inch Samuel Oschin Telescope.

Understanding a Stellar Explosion

People commonly expect that astronomy is done by a lonely astronomer peering through a telescope all night long. That idea has been wrong for more than 100 years.

Earlier this week astronomers from the Palomar Transient Factory announced the discovery of another supernova. The discovery was announced electronically via the Astronomer's Telegram, specifically #2470. The text is written for astronomers and may not be too digestible to the general public, but it and the follow-up announcement give a glimpse on how modern astronomers work to understand the universe.

I have talked about it before, but the Palomar Transient Factory uses the wide-angle 48-inch Samuel Oschin Telescope to first survey the sky. The telescope is robotically operated. Data collected from the 96-megapixel camera is beamed away via the High-Performance Wireless Research and Education Network (HPWREN) to a computing center at Berkeley where they are compared to previous images taken of the same location in the sky. In the recent case they found a faint (from our distant vantage on Earth) new supernova (named PTF 10bzf) located in an distant unnamed galaxy the night of February 23. The same portion of the sky had been previously surveyed four nights earlier and the supernova was not there. This means that the supernova was only four days old, or possibly even younger, giving astronomers a chance to catch key details of the stellar explosion as they unfold.

Typically, there is an early set of follow-up observations with the Palomar 60-inch telescope to obtain brightness and color information and then other telescopes are called into play to obtain a spectrum. To the astronomer a spectrum is essentially DNA evidence that provides key evidence toward understanding of an object or event. The Gemini North telescope on the Big Island of Hawai'i was able to provide the first spectrum of the supernova, allowing astronomers to classify this outburst as a "broad-line Type Ic supernova".

Type Ic supernovae are thought to be produced by the collapse of massive stars that have had their outer layers stripped away. Some of these events may also give rise to gamma-ray bursts.

To study the supernova further astronomers began a multi-wavelength follow-up campaign. Just as a doctor may use a variety of instruments to diagnose a person's ailment, astronomers use a wide variety of telescopes, that peer into different parts of the electromagnetic spectrum, to diagnose and understand the mechanics of what happens as a star explodes.

The first reports of those observations are just starting to roll in.

Telegram #2471 reports observations from NASA's Swift satellite which can detect gamma-rays and X-rays. These are types of light that are very short in wavelength and very high in energy. Because these types of light are absorbed by Earth's atmosphere satellites, like Swift are essential in letting astronomers probe

The next report of observations, telegram #2473, came from the Combined Array for Research in Millimeter-wave Astronomy (CARMA) facility located in Cedar Flat, CA. CARMA looks at light that is longer in wavelength than visible (or even infrared) light, but shorter than what most people call radio waves.

Other telescopes have likely already been called into action. Observations will continue across many wavelengths of light, possibly for months to come as the supernova evolves. The analysis of the details of this supernova explosion will also take many months as astronomers work to piece together the story of how and why this star died.

Thursday, March 11, 2010

Dark Sky Giveaway and More!

March must be light pollution month. The International Dark-sky Association is running a contest - the Dark Sky Giveaway.

Yes, if you make a donation to the IDA and you can help fight light pollution and you might win a sweet set of fine eyepieces.

Speaking of light pollution, don't forget that GLOBE at Night continues until March 16 and that is followed by Earth Hour at 8:30 p.m. (local time everywhere) on March 27. Be sure to check out their 2010 video.

Monday, March 8, 2010

Palomar History Photo of the Week: March 8, 2010

For over seven decades the headquarters for Palomar Observatory were located on the campus of the California Institute of Technology in the Robinson Astrophysics Laboratory. Here is a photo, taken by Ferdinand Ellerman, of the old astrophysics lab taken in the fall of 1934:

Normally, when I use a photo of a car I blur the license plate, but in this case I don't think that it matters any more.

Last year Caltech astronomy relocated their headquarters across the street to the new Cahill Center for Astronomy and Astrophysics.

Friday, March 5, 2010

Astrophoto Friday: Lagoon Nebula

This week's astrophoto is of the Lagoon Nebula (aka M8 and NGC 6523). The photo was taken by Milton Humason the night of May 15, 1950 with the Hale Telescope at prime focus.

Compare this with a color photo of the Lagoon taken about a decade later.

Talk on Palomar

On Saturday March 13 at 11:00 a.m. I will be speaking at the San Diego Archaeological Center on the construction of Palomar's 200-inch telescope. I gave the talk last November, but since then we have had many new images come our way. The net result is that this time around I will be showing off many images that most people have never seen.

As an example of a nice shot, that likely will not make the final cut for my talk, here is a picture taken by Lee A. Farnsworth, Jr. that was scanned just yesterday:

Written on the back of the print; "Oct. 18, 1937 East side 200" dome." My problem in preparing my talk is that I have too much material.

We have many more pictures and the scanning continues.

Thursday, March 4, 2010

GLOBE at Night 2010 is Underway!

From now until March 16 you can participate in GLOBE at Night. It is easy, fun and free. In the process you can help evaluate the effect that city lights have in creating light pollution.

From their press release:

With half of the world’s population now living in cities, many urban dwellers have never experienced -- and maybe never will -- the wonderment of pristinely dark skies. This loss, caused by light pollution, is a concern on many other fronts as well: safety, energy conservation, cost, health, and effects on wildlife. Yet, even though light pollution is a serious and growing global concern, it's one of the easiest environmental problems that you can address on local levels.

Participation in the international star-hunting campaign, GLOBE at Night, helps to address the light pollution issue locally as well as globally. From March 3rd to 16th, 2010, everyone all over the world is invited for a 5th year to record the brightness of the night sky. The campaign is easy and fun to do: first, you match the appearance of the constellation Orion with simple star maps of progressively fainter stars. Then you submit your measurements online, including the date, time, and location of your comparison. After all the campaign's observations are submitted, the project's organizers release a map of light-pollution levels worldwide. Over the last four annual campaigns, volunteers from more than 100 nations have contributed 35,500 measurements. Nearly 45% of these came during last year’s campaign as part of the celebration of the International Year of Astronomy (IYA).

"One of the most creative examples of GLOBE at Night participation in IYA2009 was a community-wide effort in Indiana," says Connie Walker of NOAO, director of the GLOBE at Night program. Thousands of students from a school district observed Orion from their backyards, and these kids ended up contributing 20% of the 2009 GLOBE at Night data. But they did not stop there. They demonstrated how much darkness they'd lost by building a 3-D model of the land area covered by their data. Starting with 35,000 Lego blocks stacked six layers high (the higher the stack the darker the sky), they took away 12,000 blocks to represent a sky nine times brighter than an ideal sky. The students presented their findings to local leaders and were honored for their efforts.

"Monitoring our environment will allow us as citizen-scientists to identify and preserve the dark sky oases in cities and locate areas where light pollution is increasing," says Walker. "All it takes is a few minutes during the March 2010 campaign to measure sky brightness and contribute those observations on-line. Help us exceed the 15,700 observations contributed last year. Your measurements will make a world of difference."

Tuesday, March 2, 2010

Pluto Files on PBS Tonight

Tonight (check your local listings) PBS airs a new episode of NOVA: The Pluto Files. The show is based on the book by Neil deGrasse Tyson.

While I have not yet seen the program I expect it likely that the show will have some of Caltech's Mike Brown and some discussion of Palomar, the discovery of Eris, an outer solar system world that is larger than Pluto.

Monday, March 1, 2010

Palomar History Photo of the Week - March 1, 2010

I don't know too much about the picture below, just the following. It was taken in 1934 and it shows a man with a "24-inch German-type grinding & polishing machine."

Given the source of the picture, it was most likely taken at Caltech. From another photo I know that the optician's last name is Norman, but that is all. I would love to hear if anyone has his full name or some information about him.