2 Short Mirror Wash Videos

Here is a short video showing the 200-inch mirror as it looked just before it was washed nearly two weeks ago:

And another short clip showing the wash in progress:

I recorded a *much* longer video showing the entire wash. Hopefully, I'll get a time-compressed version of that posted soon.

Under the Big Eye

Here's a rare view of the Hale Telescope that was taken during last week's mirror wash:


The photo was taken from under the telescope (with the camera on the observing floor) when the mirror was pulled out and the mirror cover partially open. On the left (south) is the coudé arch and on the right (north) is the horseshoe.

More photos from the mirror wash engineering run will be posted later in the week.

Black Friday Tours Return

It is the holiday season and we are celebrating by offering special daytime tours of the 200-inch Hale Telescope on Black Friday (the day after Thanksgiving), Friday November 26.


Our regular public tours do not resume again until April, so this may be your last chance to get a guided tour of the Big Eye for some months.

Tour tickets will be sold in the gift shop the day of the tour on a first-come, first-served basis. No prior reservations are taken. Tour tickets are $8.00. The tours are not recommended for children under six years of age.

Do keep in mind that it is COLD inside the dome. Temperatures inside, where the hour-long tours take place, are expected to be around 40F. So bundle up!

Rough Weather for the Weekend

Dense fog, high winds, heavy rain & snow are all in the forecast for Palomar Mountain this weekend. The National Weather Service has issued a Special Weather Statement.

Travel to Palomar Mountain is likely not a good idea for the weekend.

200" Mirror Wash - Update

The washing of the 200-inch mirror was completed on Thursday and the Big Eye is now back in the telescope.

I took several hundred photos of the event and it will likely be sometime next week before the best of them are posted here. In the meantime, let me show you what it was all about with a before and after photo of our 14.5 ton glass mirror.

That is a dramatic difference and a job well done by the Palomar crew.

Mirror Wash 2010 - Day 1

The engineering run to wash the 200-inch mirror is going well. Yesterday the mirror was successfully pulled from the telescope. Here are some photos from the first day of engineering.

The Hale Telescope with the Cassegrain instrument and Cassegrain cage removed.

A view of the mirror cell. The 36 mirror supports, serviced earlier this year, are visible.


The mirror cart under the Hale Telescope, ready to receive the 200-inch mirror.

The Palomar crew pushing the mirror cart, loaded with the 200-inch mirror, over to the washing area in the dome northwest of the telescope.

For more immediate updates & photos be sure to follow palomarskies on twitter and/or "like" Palomar Observatory on Facebook.

Watch the Webcam Today

Here is a capture from the Hale Telescope webcam taken early this morning at the end of a long (12.8 hour) observing session.


Today should be an interesting day to watch the Hale Telescope webcam as we are pulling the 200-inch mirror out of the telescope today so that we may wash the mirror tomorrow.

I'll be posting pictures of the event as they come in.

Allan Sandage, 1926 - 2010

Observational cosmologist Allan Sandage has passed away. In memory of his brilliant career our history photo of the week is 1950s photo of Dr. Sandage in front of the 200-inch Hale Telescope.
You can read summaries of his impressive career from Carnegie Observatories, Nature, Astronomy Now, and Sky & Telescope.

Hale Telescope Under Moonlight

Here are two photos of the 200-inch Hale Telescope illuminated by moonlight. Both were taken on Friday November 12, 2010.

The Hale Telescope is used virtually every clear night of the year for astronomical research. The research mission on that particular night was imaging and spectroscopy of ultra luminous infrared galaxies discovered by the Wide-field Infrared Survey Explorer mission.

Astrophoto Friday - the California Nebula

This week Astrophoto Friday brings us the California Nebula.


The California Nebula (also known as NGC 1499) is an emission nebula consisting largely of ionized hydrogen gas. It was named for its resemblance to the state of California - home to the Palomar Observatory. The nebula is located approximately 1,000 light years from our solar system in the direction of the constellation of Perseus.

The bright blue star Xi Persei (to the right of the nebula) most likely is the source of illumination for the nebula.

This image is a composite from two black and white images taken with the Palomar Observatory's 48-inch (1.2-meter) Samuel Oschin Telescope as a part of the Second Palomar Observatory Sky Survey (POSS II). The images were recorded on two glass photographic plates - one sensitive to red light and the other to blue. The plates were scanned and color combined to produce the image seen here.