Home Where We Discovered Our Place in the Universe Due to the Pandemic, Most Public Activities Have Been Suspended. For the Current Status of the Cosmic Café, Observatory Buildings and Grounds, Please Check the Homepage Below. VISIT US DONATE

Mount Wilson Observatory Status

Angeles National Forest is CLOSED due to the extreme fire hazard conditions. To see how the Observatory is faring during the ongoing Bobcat Fire, check our Facebook link, Twitter link, or go to the HPWREN Tower Cam and click on the second frame from the left at the top, which looks east towards the fire (also check the south-facing cam and the recently archived timelapse movies below which offer a good look at the latest events in 3-hour segments. Note to media: These images can be used with credit to HPWREN). For the latest updates on the Bobcat fire from U.S. Forest Service, please check out their Twitter page.

 

Monday night (9/21) the firefighters set additional strategic backfires to make an emergency barrier to the Bobcat Fire on our northern and western flanks. These strategic firings were conducted along Red Box Road to the Observatory as well and will continue all the way down the road to route 2, the Angeles Crest Highway.  To see a 9/21 timelapse video looking west towards the broadcast towers click here. For a view to the north from the same time frame click here. Click here to watch another scary timelapse from the night of 9/17, when the Observatory was in greatest jeopardy. Almost all forest around the Observatory has now burned. After being in great peril twice, we seem to be out of immediate danger now. The ground crews on the mountain will remain to make sure nothing gets by as fire tends to linger in the canyons below. The firefighters are our heroes and we owe them our existence. They are true professionals, artists with those backfires, and willing to put themselves at considerable risk to protect us. We thank them!!!!

 


To view an extraordinary record of the Bobcat Fire click here. It is a 360 degree, panoramic, time-lapse video of the fire as it started and eventually came up and around the Observatory. The video, “Bobcat Fire Time Lapse from Mt. Wilson 9/4/20-9/19/20” was created by Siobhán Dougall, who stitched together 10,500 images recorded by our four HPWREN tower cams.

 

Read a Letter of Thanks from our chairman Sam Hale please go here.

 Photo: David Cendejas, Mount Wilson Superintendent

To recover from the Bobcat Fire and the loss of revenue from the pandemic, Mount Wilson Observatory needs your help! If you can, please make a donation, join with a supporting membership, spread the word by helping out with our GoFundMe campaign, or send us a check the old fashion way at:      Mount Wilson Institute,   P.O. Box 94146,   Pasadena, CA 91109.    Our largely volunteer organization receives no regular support from any institutions or government, so any help we get from the public during this tough year is greatly appreciated!!! Thanks to those who have given to us recently in our many hours of need!

For the first half of the 20th Century, Mount Wilson was the most famous observatory in the world. The biggest telescopes were here, and their new designs were changing the way astronomy was done. Among the many discoveries made on the mountain, a few revolutionized our understanding of our place in the Universe. Here, during WWI, Harlow Shapley measured the size of the Milky Way Galaxy for the first time and located our position in it, far from the center. Then, in 1924, Edwin Hubble proved that the mysterious spiral nebulae, which astronomers had speculated about for decades, were in fact distant galaxies similar to our own. Then Hubble teamed up with Milton Humason and confirmed that this immense Universe was expanding. Space itself was getting bigger. This finding, when run backwards in time, led a few decades later to the Big Bang Theory. Mount Wilson is where modern observational cosmology began. It holds a unique place in humanity’s search for our most distant origins. Today, our original solar and nighttime telescopes, the world’s largest for two generations of astronomers, have been joined by the new CHARA array, which has the highest resolution of any optical or infrared system ever built, achieving unprecedented views of the stars.

A publicity photo of astronomer Edwin Hubble guiding Mount Wilson’s 100-inch Telescope in 1924, shortly after he proved the existence of distant galaxies. Photo: Carnegie Observatories/ Huntington Library.

Due to the pandemic, Mount Wilson Observatory is currently CLOSED. During this public health crisis, there will be NO parking, cafe service, tours, telescope observing, or other public events. This message supersedes all other information on the website.

Hikers are allowed to pass through and get water.

 

If you are on the Observatory grounds, state law requires you to wear a mask or face covering. Please keep social distancing going on the trails and on the Observatory grounds. Covid-19 numbers are currently going up in Southern California. Thank you for your cooperation!

 

Mars!

Mars, imaged with Mount Wilson’s 60-inch Telescope on October 18, five days after opposition and its closest approach to Earth until 2035. Astrophotographer Blake Estes and our executive director and telescope operator Tom Meneghini waited patiently for Mount Wilson’s famous seeing to capture the red planet in amazing detail.

Subscribe to Mount Wilson Observatory News for updates on what is (or isn’t) happening on the mountain in 2020. Click here.


The Summer Issue of our Quarterly Newsletter, Reflections is Now Available Online.

Click here to read the Summer issue of our newsletter and get a quick update on our status during the pandemic.

The feature article is the second part of the story of how Mount Wilson astronomers measured, for the first time, the size of a star (other than the Sun). This monumental achievement was made in the fall of 1920, nearly one hundred years ago. To read the first part, see last December’s issue of Reflections here. The followup article in this issue details how Walter Adams, the second director of the Observatory, figured out how to measure distances to thousands of stars, a prerequisite to determining their sizes. When Mount Wilson Observatory was founded, only about 60 stellar distances were known. Adams developed a whole new way to determine distances to stars called spectroscopic parallax. It became an essential rung on the “cosmic distance ladder,” by which astronomers measure the Universe. While Hubble’s work is relatively well known, these two articles offer a good introduction into some of the more obscure ways that astronomers on the mountain used astrophysics to revolutionize their field.

Our Executive Director, Tom Meneghini, updates us on the 100-inch Telescope shutter repair and our current state of affairs. There is also a short article on the Snow Solar Telescope renovation and a big thank you to our 2020 supporters.

Explore Mount Wilson in Person

Explore Mount Wilson in Person

Explore Mount Wilson On-Line

Explore Mount Wilson On-Line

Support Mount Wilson Observatory

Support Mount Wilson Observatory

  • Become a Member of the Observatory!
  • Help keep the Observatory operations going and preserve its famous telescopes for future generations, Donate!
  • Join the people who keep the Observatory programs going, Volunteer.

Comet C/2020 F3 (NEOWISE)!

Comet Neowise captured by Mount Wilson’s Blake Estes on the Evening of July 17th. Note the beautiful, blue ion tail.

Mount Wilson Observatory’s Blake Estes imaged Comet Neowise as it rose above the San Gabriel Mountains into the morning twilight around 4:45 AM, on Monday, July 13. His images, with the 100-inch Telescope dome in the foreground, were taken from the 150-foot Solar Tower Telescope.

Another shot of the Comet Neowise by Estes. To the right is the bright star Aldebaran in the constellation Taurus.

Another shot with the lights of Los Angeles.  The comet made its closest approach to Earth on July 23, and is fading rapidly as it speeds away from the Sun towards the far reaches of our Solar System, not to return for 6,000+ years.

Mount Wilson Observatory’s New Membership Program

Join the Observatory  as a member! By doing so, you get a number of benefits and you help us renew this historic mountaintop, so that it may inspire well into the future. We aim to build a larger community to keep us moving forward with educational STEM programs, undergraduate research, public outreach, ongoing scientific research, and restoration of our 116-year-old observatory.

Please consider becoming a member in 2020, to help us through this year. If you can. Sign up for the individual membership, family membership, or a higher level, all named after one of our famous astronomers. Sign up is easy. Click here to go to our membership page.

What’s that Strange Light on Top of Mount Wilson?

Called Sunstar, it is an array of six prisms which take incoming sunlight and refract it, bending the light and spreading it into a spectrum–all the colors of the rainbow. It is mounted near the top of the Observatory’s 150-foot Solar Telescope Tower. With motion controls, it can be remotely directed to project the spectrum to a specific point in the Los Angeles basin. An observer below will see an intense point of light in a single wavelength, shining like a brilliant jewel from the ridgeline of Mount Wilson, 5800 feet above in the San Gabriel Mountains. The prisms can be moved to change the color of light an observer sees, or the observer can walk in one direction or another to change the color. In this case, the observer is actually walking across a giant spectrum some 250 yards long. While still very bright, at the great distances involved, it is perfectly safe to look at a single wavelength of sunlight. For more information and a schedule, go to our Sunstar page.

The centennial, paper architectural model of the 100-inch Telescope is now available to download for a small donation to Mount Wilson Observatory. Click here to go to the model page.

George Ellery Hale, 1910. Photo: Carnegie/ Huntington Library

The Observatory’s founder, George Ellery Hale, built four telescopes, each one in succession becoming the largest in the world. Here they are shown to the same scale. His first was the 40-inch refractor at Yerkes  (in Wisconsin) on the left, but then he began building the more revolutionary–and more compact–reflector telescopes, using a large mirror instead of a lens. His next two are on Mount Wilson, the 60-inch and the 100-inch. (While not quite as grand as his last, these two had the light-gathering power for astronomers to discover our place in the expanding Universe.) His fourth, the 200-inch Hale Telescope at Palomar, is represented on the right by one of Russell Porter’s famous cutaway drawings. This image has been reversed and extended on the left side for a better comparison of the relative sizes of the full domes. Hale’s telescopes were the biggest from 1897, when Yerkes opened, to 1993, when the Keck telescope in Hawaii was completed–a span of 96 years. To see these drawings enlarged, click here. Drawing credits: University of Chicago/Yerkes Observatory, Carnegie Observatories, Palomar Observatory/Caltech.

To view our Facebook feed, please click here.

 

Wednesday, October 21st, 2020 at 1:41am
Apple Cider, our refugee juvenile California Black Bear, is boldly out for a stroll in the afternoon. We are seeking resources to relocate him/her before cold winter weather sets in. (Photos by Blake Estes) https://t.co/hVP7682ojc MtWilsonObs photo
Sunday, October 18th, 2020 at 8:10pm
With all of the surrounding devastation in the forest, the Observatory is becoming something of refuge for the displaced, including our most recent ursid addition, "Apple Cider". #bobcatfire https://t.co/ArcvYxOZ7o MtWilsonObs photo
Sunday, October 18th, 2020 at 1:52pm
Mars imaged through the 60" telescope this morning. (Image capture and processing - Blake Estes; telescope operation - Tom Meneghini) #mars #astronomy https://t.co/aYGW88svJq MtWilsonObs photo
Saturday, October 10th, 2020 at 3:06am
Although Angeles Crest Hwy will be open, Mt. Wilson Red Box Road will be restricted to residents, employees and contractors. Public access to the observatory will not be possible until further notice. https://t.co/lcm5aaPQvw
MtWilsonObs photo
Angeles_NF @Angeles_NF
Closure UPDATE: The USFS emergency closure order for the Angeles National Forest expired last night. Much of the ANF reopens today, Oct 9. Please note: BURN ZONES remain CLOSED for public safety, fire recovery & restoration. THANK YOU for your patience & understanding! #ANF https://t.co/FX8PK1G863