Mount Wilson Observatory
@mtwilsonobs.bsky.social
Where we discovered our place in the universe.
www.mtwilson.edu
www.mtwilson.edu
Behind the scenes at the 150-Foot Solar Tower: our Technical Services volunteers recently completed critical maintenance to help preserve this 124-year-old solar research instrument for the future. Video: Rob Skinner
February 9, 2026 at 5:34 PM
Behind the scenes at the 150-Foot Solar Tower: our Technical Services volunteers recently completed critical maintenance to help preserve this 124-year-old solar research instrument for the future. Video: Rob Skinner
Completed in 1912, the 150-ft Solar Tower became one of history’s most important solar instruments. Since 1917, astronomers here have kept the world’s longest continuous hand-drawn sunspot record—still vital to solar science today.
February 4, 2026 at 5:48 PM
Completed in 1912, the 150-ft Solar Tower became one of history’s most important solar instruments. Since 1917, astronomers here have kept the world’s longest continuous hand-drawn sunspot record—still vital to solar science today.
Seeking enthusiastic communicators! Love Mount Wilson Observatory? Join our Docent Team. Training starts March 2026—no astronomy background required. Lead weekend tours and help bring Mount Wilson’s scientific legacy to life. Apply: mtwilson.edu/docents
February 4, 2026 at 5:42 PM
Seeking enthusiastic communicators! Love Mount Wilson Observatory? Join our Docent Team. Training starts March 2026—no astronomy background required. Lead weekend tours and help bring Mount Wilson’s scientific legacy to life. Apply: mtwilson.edu/docents
Completed in 1908, Mount Wilson’s 60-foot Solar Tower transformed solar observing with daily, precise studies of sunspots and motion. Using it, George Ellery Hale identified magnetic fields on the Sun—revealing magnetism as a universal force and helping define modern solar physics.
January 28, 2026 at 6:35 PM
Completed in 1908, Mount Wilson’s 60-foot Solar Tower transformed solar observing with daily, precise studies of sunspots and motion. Using it, George Ellery Hale identified magnetic fields on the Sun—revealing magnetism as a universal force and helping define modern solar physics.
We miss you too! Big plans are brewing for our 2026 season—concerts, lectures, tours, movies & more. The Cosmic Café and public tours return weekends in mid-April, with public events in May. Want the scoop? Join our mailing list or follow along here. See you on the mountain soon!
bit.ly/mwosignup
bit.ly/mwosignup
January 28, 2026 at 6:32 PM
We miss you too! Big plans are brewing for our 2026 season—concerts, lectures, tours, movies & more. The Cosmic Café and public tours return weekends in mid-April, with public events in May. Want the scoop? Join our mailing list or follow along here. See you on the mountain soon!
bit.ly/mwosignup
bit.ly/mwosignup
Brought from Yerkes Observatory in 1904, the Snow Solar Telescope was the first instrument at the Mount Wilson Solar Observatory. It enabled early studies of sunspots and solar spectra, helping lay the foundation of modern solar physics—and still inspires visitors today.
January 20, 2026 at 10:18 PM
Brought from Yerkes Observatory in 1904, the Snow Solar Telescope was the first instrument at the Mount Wilson Solar Observatory. It enabled early studies of sunspots and solar spectra, helping lay the foundation of modern solar physics—and still inspires visitors today.
Thanks to you, Mount Wilson Observatory begins 2026 strong. We’re deeply grateful to the members and donors who supported our year-end campaign - every gift helps preserve a century of discovery. Thank you, and we can’t wait to welcome you back for concerts, lectures, and nights under the stars!
January 20, 2026 at 10:12 PM
Thanks to you, Mount Wilson Observatory begins 2026 strong. We’re deeply grateful to the members and donors who supported our year-end campaign - every gift helps preserve a century of discovery. Thank you, and we can’t wait to welcome you back for concerts, lectures, and nights under the stars!
“It cannot too often be repeated that the Sun is the only star whose phenomena can be studied in detail.” With these words, George Ellery Hale set the vision for the Mount Wilson Solar Observatory - where solar research was central from the very beginning.
January 13, 2026 at 11:33 PM
“It cannot too often be repeated that the Sun is the only star whose phenomena can be studied in detail.” With these words, George Ellery Hale set the vision for the Mount Wilson Solar Observatory - where solar research was central from the very beginning.
With Mount Wilson Observatory’s STEM Program, students visit the mountaintop where humanity discovered its place in the universe. Einstein, Hawking, and Carl Sagan all came here—now today’s students can too. Know a teacher or school group? Please share! Learn more: www.mtwilson.edu/stem
January 13, 2026 at 11:15 PM
With Mount Wilson Observatory’s STEM Program, students visit the mountaintop where humanity discovered its place in the universe. Einstein, Hawking, and Carl Sagan all came here—now today’s students can too. Know a teacher or school group? Please share! Learn more: www.mtwilson.edu/stem
Winter hours at Mount Wilson: open daily 10AM–4PM with the museum, 100-inch gallery & restrooms open. Café and public tours return in spring; private tours available by booking.
❄️ Road conditions change quickly - check LA County road closures before visiting.
❄️ Road conditions change quickly - check LA County road closures before visiting.
January 2, 2026 at 6:51 PM
Winter hours at Mount Wilson: open daily 10AM–4PM with the museum, 100-inch gallery & restrooms open. Café and public tours return in spring; private tours available by booking.
❄️ Road conditions change quickly - check LA County road closures before visiting.
❄️ Road conditions change quickly - check LA County road closures before visiting.
Safety first: because of poor road conditions, the Cosmic Café will be closed tomorrow (Sat Dec 27) and the 11:30AM tour has been canceled. We’ll keep you posted about Sunday. Thank you for your patience and understanding!
December 26, 2025 at 6:23 PM
Safety first: because of poor road conditions, the Cosmic Café will be closed tomorrow (Sat Dec 27) and the 11:30AM tour has been canceled. We’ll keep you posted about Sunday. Thank you for your patience and understanding!
Explore the historic telescopes that changed astronomy! Saturday tours at 11:30AM thru Dec 27 (weather permitting). Start at the Cosmic Café, join the tour, stay for the views. A perfect winter outing - and our merch table has great last-minute gifts!
December 17, 2025 at 5:50 PM
Explore the historic telescopes that changed astronomy! Saturday tours at 11:30AM thru Dec 27 (weather permitting). Start at the Cosmic Café, join the tour, stay for the views. A perfect winter outing - and our merch table has great last-minute gifts!
The 60-inch telescope keeps running thanks to the dedication of people like Bill Leflang (L), shown here reviewing its control systems with our Technical Services Team. Many of the systems Bill designed decades ago remain essential to its performance today. Photo: Rob Skinner
December 17, 2025 at 5:48 PM
The 60-inch telescope keeps running thanks to the dedication of people like Bill Leflang (L), shown here reviewing its control systems with our Technical Services Team. Many of the systems Bill designed decades ago remain essential to its performance today. Photo: Rob Skinner
Unfortunately, this Saturday’s Star Party is canceled due to forecasted clouds. We’re grateful to everyone who planned to join us and to the LAAS volunteers who make these events possible. Thanks for understanding—we’ll share next season’s schedule in early spring! ✨
December 12, 2025 at 9:30 PM
Unfortunately, this Saturday’s Star Party is canceled due to forecasted clouds. We’re grateful to everyone who planned to join us and to the LAAS volunteers who make these events possible. Thanks for understanding—we’ll share next season’s schedule in early spring! ✨
Hiking, biking, or driving up Angeles Crest? The Cosmic Café is your warm rest stop at the top of the world—open weekends 10–4 through Dec 28. Hot food, warm drinks & great views. Saturday tours at 11:30AM. Just a few weekends left before we close for the season!
December 9, 2025 at 11:00 PM
Hiking, biking, or driving up Angeles Crest? The Cosmic Café is your warm rest stop at the top of the world—open weekends 10–4 through Dec 28. Hot food, warm drinks & great views. Saturday tours at 11:30AM. Just a few weekends left before we close for the season!
THIS SATURDAY, DEC 13 — FREE STAR PARTY! ✨
(Weather permitting—check our socials Friday!)
Join us for the final star party of the season, sunset to midnight, with LAAS volunteers sharing incredible views through their telescopes. Enter through the main gate.
Info: www.mtwilson.edu/star-parties
(Weather permitting—check our socials Friday!)
Join us for the final star party of the season, sunset to midnight, with LAAS volunteers sharing incredible views through their telescopes. Enter through the main gate.
Info: www.mtwilson.edu/star-parties
December 9, 2025 at 10:58 PM
THIS SATURDAY, DEC 13 — FREE STAR PARTY! ✨
(Weather permitting—check our socials Friday!)
Join us for the final star party of the season, sunset to midnight, with LAAS volunteers sharing incredible views through their telescopes. Enter through the main gate.
Info: www.mtwilson.edu/star-parties
(Weather permitting—check our socials Friday!)
Join us for the final star party of the season, sunset to midnight, with LAAS volunteers sharing incredible views through their telescopes. Enter through the main gate.
Info: www.mtwilson.edu/star-parties
Mount Wilson depends on supporters who care about preserving our cosmic legacy. A year-end gift or membership keeps our telescopes, domes & programs thriving for future generations. Give before Dec 31: www.mtwilson.edu/support-us
December 9, 2025 at 10:55 PM
Mount Wilson depends on supporters who care about preserving our cosmic legacy. A year-end gift or membership keeps our telescopes, domes & programs thriving for future generations. Give before Dec 31: www.mtwilson.edu/support-us
Can’t get to the mountain for holiday shopping at our merch store? No problem! 🎁
Find Mount Wilson merch online at www.mtwilson.edu/merch - every purchase supports the Observatory.
Find Mount Wilson merch online at www.mtwilson.edu/merch - every purchase supports the Observatory.
December 2, 2025 at 9:15 PM
Can’t get to the mountain for holiday shopping at our merch store? No problem! 🎁
Find Mount Wilson merch online at www.mtwilson.edu/merch - every purchase supports the Observatory.
Find Mount Wilson merch online at www.mtwilson.edu/merch - every purchase supports the Observatory.
Big news: The Cosmic Café is staying open weekends through Dec 28! Enjoy our winter menu 10AM–4PM - chili, vegan tomato soup, hot drinks & sweet treats - plus stunning mountain views.
Saturday tours at 11:30AM (weather permitting). Come up and say hello!
Saturday tours at 11:30AM (weather permitting). Come up and say hello!
November 26, 2025 at 12:11 AM
Big news: The Cosmic Café is staying open weekends through Dec 28! Enjoy our winter menu 10AM–4PM - chili, vegan tomato soup, hot drinks & sweet treats - plus stunning mountain views.
Saturday tours at 11:30AM (weather permitting). Come up and say hello!
Saturday tours at 11:30AM (weather permitting). Come up and say hello!
Please note: the Observatory gates will be closed on Thanksgiving Day. We’re grateful for our members, donors, staff, and dedicated volunteers - your support keeps this historic site thriving. THANK YOU!
(Photo: Andrew Carnegie & George Ellery Hale, 1910)
(Photo: Andrew Carnegie & George Ellery Hale, 1910)
November 26, 2025 at 12:05 AM
Please note: the Observatory gates will be closed on Thanksgiving Day. We’re grateful for our members, donors, staff, and dedicated volunteers - your support keeps this historic site thriving. THANK YOU!
(Photo: Andrew Carnegie & George Ellery Hale, 1910)
(Photo: Andrew Carnegie & George Ellery Hale, 1910)
It’s been a landmark year at Mount Wilson - sold-out concerts, new film nights, and first-time visitors marveling at the 100-inch telescope. As we celebrate 120+ years of discovery, your support keeps our legacy alive. Join or donate: www.mtwilson.edu/support-us
November 26, 2025 at 12:02 AM
It’s been a landmark year at Mount Wilson - sold-out concerts, new film nights, and first-time visitors marveling at the 100-inch telescope. As we celebrate 120+ years of discovery, your support keeps our legacy alive. Join or donate: www.mtwilson.edu/support-us
The Cosmic Café is open weekends 10–4! ☕🌭
Grab hot drinks, chili, vegan tomato soup, hot dogs, sandwiches, sweet treats & more. Stay warm with hoodies, beanies, jackets and cozy socks.
Docent-led Observatory tours: Sat & Sun at 11:30 & 1:00.
Come hungry, leave happy!
Grab hot drinks, chili, vegan tomato soup, hot dogs, sandwiches, sweet treats & more. Stay warm with hoodies, beanies, jackets and cozy socks.
Docent-led Observatory tours: Sat & Sun at 11:30 & 1:00.
Come hungry, leave happy!
November 19, 2025 at 6:53 PM
The Cosmic Café is open weekends 10–4! ☕🌭
Grab hot drinks, chili, vegan tomato soup, hot dogs, sandwiches, sweet treats & more. Stay warm with hoodies, beanies, jackets and cozy socks.
Docent-led Observatory tours: Sat & Sun at 11:30 & 1:00.
Come hungry, leave happy!
Grab hot drinks, chili, vegan tomato soup, hot dogs, sandwiches, sweet treats & more. Stay warm with hoodies, beanies, jackets and cozy socks.
Docent-led Observatory tours: Sat & Sun at 11:30 & 1:00.
Come hungry, leave happy!
This 1910 photo shows scientists from across the globe at Mount Wilson for the Fourth Conference on Solar Research—an early effort to coordinate international astronomy. H.C. Wilson later called it “a remarkable meeting” for its people, purpose, and place.
November 19, 2025 at 6:48 PM
This 1910 photo shows scientists from across the globe at Mount Wilson for the Fourth Conference on Solar Research—an early effort to coordinate international astronomy. H.C. Wilson later called it “a remarkable meeting” for its people, purpose, and place.
🌧️ Weather Update: Due to the rainy conditions, all docent tours at the Observatory are cancelled this weekend (Nov 15-16). Stay dry, and we’ll see you on the mountain again soon!
November 14, 2025 at 7:41 PM
🌧️ Weather Update: Due to the rainy conditions, all docent tours at the Observatory are cancelled this weekend (Nov 15-16). Stay dry, and we’ll see you on the mountain again soon!
Aurora over Mount Wilson!
The North Tower Cam caught a rare glimpse of the northern lights around 8:45 PM on Nov 11 — caused by a strong geomagnetic storm from a recent solar flare.
The North Tower Cam caught a rare glimpse of the northern lights around 8:45 PM on Nov 11 — caused by a strong geomagnetic storm from a recent solar flare.
November 12, 2025 at 9:49 PM
Aurora over Mount Wilson!
The North Tower Cam caught a rare glimpse of the northern lights around 8:45 PM on Nov 11 — caused by a strong geomagnetic storm from a recent solar flare.
The North Tower Cam caught a rare glimpse of the northern lights around 8:45 PM on Nov 11 — caused by a strong geomagnetic storm from a recent solar flare.