Palomar Observatory Chronology
For narrative and context, please refer to the Palomar
page, as well as the individual pages for the Hale,
Samuel Oschin, 60-inch,
and 18-inch telescopes.
Palomar history graphical timeline (
). Time starts in 1920 and flows to the right; use the scroll bar to
reach the 2010s. Each column corresponds to a decade, vertical lines indicate years. Rows indicate category:
general or individual telescopes. Darker background shows when the telescope was operational. Each event is
shown as a bar whose width indicates time span. Hovering with mouse over an event will bring up a short
explanation. Hint: use the keyboard shortcuts (no shift) control/command + to zoom in,
control/command − to zoom out, and control/command 0 to reset. Thumbnails: Palomar/Caltech,
Rockefeller grant: awarded June 1928 [ es98]
Site selection: 1929 – 1934 [ a42]
Instrument shop: completed 1931; optical shop: completed 1933 [ es48]
Site work: September 1935 – end of 1938 [ a42]
Hale Telescope 1:10 scale model: conceived and designed 1935, completed 1937 [ md35] [ es37]
Radio antenna: installed ca. April 1956, moved to OVRO 1958
[ es56] [ ai56] [ es58] [ es94] Mt. Wilson and Palomar become the
Hale Observatories: 1970 [ es48] [ es70] [ cis] 18-inch Schmidt Telescope
Dome construction: winter 1935/36 – early summer 1936 [ md39]
Telescope fabrication: 1935 – 1936 [ ai36] [
z65] [ z73] [ s04]
First light: 5 September 1936 [ z73]
Supernova search: September 1936 – January 1942 (interrupted by WWII), resumed ca. May 1954,
planned to be continued past 1975 [ z59] [
w60] [ z64] [ khs76]
Clustering of galaxies observations: 1937 – 1942 (interrupted by WWII), 1950 – ca. 1957?
[ z37] [ z38] [
z50] [ hwz57]
Nova search: July – October 1950 [
hz51] [ iaj51] [ z64]
Upgrades: overhauling and partial revision of optics in 1959 for 8 months
Palomar Planet-Crossing Asteroid Survey (PCAS): January 1973 – June 1995
[ hs79] [ hea97]
Palomar Asteroid and Comet Survey (PACS): September 1982 – December 1994
Comet Shoemaker-Levy 9: discovered 24 March 1993 [ s96]
On public display: since 22 September 2013; the
Helin exhibit was dedicated on 14 June 2014 48-inch Samuel Oschin Telescope
Planning: ca. May 1937 – 1938 [ a42] [ f94]
Dome construction: mostly completed by 1938 [ ai38'] [ a42]
Telescope fabrication: 1939 – 1947 (interrupted by WWII)
[ md39] [ a42] [
ai46] [ ai47]
Mirror casting: October 1938; shipped to Pasadena a month later
[ cgw66] [ f94]
Optics work: Mirror ground and polished 1939 – 1940 for 5 months;
work on corrector plate interrupted by the war; optics tested on telescope September 1948 [
ai48] [ o03]
First official photograph: 29 September 1948 [ f94] [ s61]
Operational: 31 January 1949 [ z73]
National Geographic Society – Palomar Observatory Sky Survey (POSS I): 19 July 1949 (intended), 11 November 1949 (actual) – 19 December 1958
[ n49] [ b51] [ rd93]
First deep-sky color images: released April 1959 [ es59]
Palomar Supernova Search: 1958 (preliminary), ca. June 1959 – ca. December 1975
[ hg60] [
zea63] [ z64] [ z65'] [ z73] [
khs76] [ k05] [ cbat] [ psns]
Palomar – Leiden Faint Minor Planets Survey: 23 September – 25 October 1960
[ hea63] [ hea84] [ ssb07]
Palomar – Leiden Trojan Surveys: 1971, 19 September – 5 October 1973, 7 – 22 October 1977
[ hea89] [ hea91] [ ssb07]
Palomar Proper Motion Survey: September 1962 – 1971 [ l74]
Quick V: 1982 – 1984 [ lea90]
Upgrades: new achromatic corrector installed mid-1985; other upgrades (e.g., autoguider, photometer, plate holders, dark rooms)
mostly finished by mid-1987 [ rea91] [ rd93]
The Second Palomar Observatory Sky Survey (POSS II): mid-1985 – June 2000
[ rea91] [ rd93] [
poss2] [ m15] Naming/rededication as the
Samuel Oschin Telescope: 1987 [ es87]
Near-Earth Asteroid Tracking (NEAT): April 2001 – April 2007; with NEAT camera April 2001 – early 2003, later with QUEST camera
[ jpl01] [ pea01] [
hea07] [ lea08] [ poss2] [ neat]
Palomar-QUEST: July 2003 – September 2008
[ s06] [ bea09] [ sea09] [ quest]
Eris: discovered 5 January 2005 [ eris]
Palomar Transient Factory (PTF): 13 December 2008 (first light), early 2009 – late 2012
[ lea14] [ ptf]
intermediate Palomar Transient Factory (iPTF): 13 February 2013 – 2017 (projected)
[ k13] [ iptf] 200-inch Hale Telescope
Mirror casting: 25 March 1934 (unsuccessful attempt), 2 December 1934 – 25 October 1935
[ g36] [
cgw66] [ f94] [ cmog]
Transport of mirror to Caltech: March 26 – 10 April 1936 [ c86]
Mirror work: May 1936 – October 1947 at the shop, through October 1949 at Palomar
[ a42] [ f94]
Dome construction: ca. September 1936 – 1939
[ md39] [ ai38] [ a42]
Telescope design: general specs agreed upon in 1929, detailed design ca.
early 1934 – 1936; control system design completed ca. mid-1938
[ a42] [ f94]
Telescope construction: 1936 – August 1938;
parts began arriving at Palomar 25 October 1938 [ pi38] [ a42]
Transport of mirror to Palomar: 18 – 19 November 1947
[ r47] Dedication of the Observatory and the
Hale Telescope: 3 June 1948
First light: December 1947 [ es91]
First image ("second light"): 26 January 1949
[ h49] [ es91]
Operational: 12 November 1949 [ s99]
Images of Moon and planets: December 1952 [ es53]
Optical identification of radio sources: December 1952
(in conjuction with Mt. Wilson) [ es53]
Correction of distance to M31: 1952 [ b56]
New H 1958 0 value: [ s58]
Distance to quasars first determined: early 1963
[ es61] [ gs64] [ s99]
Galactic center in infrared: September 1966 [ bn68]
Electronic upgrades: 1953 – present
[ d67] [ es98] [
wo00] [ coopi]
First photoelectric photometer: ca. 1953 – 1955
[ es53'] [ es55] [ es69]
First computer system: 1971 [ es73]
Early CCDs: May 1976 – 1979
[ gw81] [ es82] [ gea87]
Four-shooter: installed 1983, used at least until 1989
[ gea84] [ gea87'] [ pea96] Adaptive optics system
PALAO: development started summer 1994, operational in December 1999
[ dea98] [
es99] [ mea00] [ k05']
PALM-3000: operational since June 2011 [ dea13] 60-inch Telescope
Planning and design: 1962 – ca. 1966
[ ai63] [ es66]
Mirror in shop: ca. February/March 1966 – ca. mid-1969
[ hi66] [ es70']
Construction: 1966 – early 1969
[ ai69] [ es70']
Computer system development: 1969 – 1970; upgrades ca. 1973
[ ai63] [ d70] [ es73]
Dedicated: 23 October 1970
[ ded70] [ hi70]
Operational: 22 March 1972
First brown dwarf confirmed: November 1995
[ sts95] [ es96]
Automated/robotic: since September 2004
Robo-AO: operational since June 2012
[ roao] References
J. Anderson (May-June 1942) The Astrophysical Observatory of the California Institute of Technology, JRASC, 36:177.
18-inch Schmidt fabrication images.
Hale Telescope dome construction images.
48-inch Schmidt dome construction images.
48-inch Schmidt fork fabrication images.
48-inch Schmidt tube fabrication images.
48-inch Schmidt corrector plate images.
Caltech Archives 60-inch telescope images.
60-inch telescope fabrication image.
I. Bowen (February 1951)
Survey of the Year's Work at the Mount Wilson and Palomar Observatories, PASP, 63:5.
W. Baade (February 1956)
The Period-Luminosity Relation of the Cepheids, PASP, 68:5.
A. Bauer et al (November 2009)
Highly Variable Objects in the Palomar-QUEST Survey: A Blazar Search Using Optical Variability, ApJ, 705:46.
E. Becklin & G. Neugebauer (January 1968)
Infrared Observations of the Galactic Center, ApJ, 151:145.
D. di Cicco (April 1986)
The Journey of the 200-inch Mirror, S&T, 71:347.
S. Cenko et al (October 2006)
The Automated Palomar 60 Inch Telescope, PASP, 118:1396.
List of Supernovae.
Corning Glass Works (1966) Survey of Technical Progress Pt 36:
Reflecting Telescope Manufacture—A Résumé of Dr. McCauley's Report
" Corning Glass Works and Astronomical Telescopes" (1965, unpublished).
Carnegie Institution of Science
Corning Museum of Glass
The Glass Giant.
Caltech Optical Observatories
Palomar Instruments Twiki.
E. Dennison (April 1967)
Electronics and the New Astronomy, E&S, 30:9.
E. Dennison (November 1970)
Computerization Comes to Palomar, E&S, 34:12.
R. Dekany et al (September 1998)
First Tip-Tilt Correction with the Palomar 200-in. Adaptive Optics System, SPIE, 3353:56.
R. Dekany et al (October 2013)
PALM-3000: Exoplanet Adaptive Optics for the 5 m Hale Telescope, ApJ, 776:130.
Caltech (3 June 1948)
of the Palomar Observatory and the Hale Telescope.
Hale Observatories (23 October 1970)
Dedication of the Sixty-Inch Telescope
and the Oscar G. Mayer Building of the Hale Observatories.
The Discovery of Eris, the Largest Known Dwarf Planet.
Caltech (September 1937)
The Month at Caltech: Scale Model of the 200" Completed, E&S (AR), 1(2):8.
Caltech (June 1948)
Palomar Issue, E&S, 11(6):all.
Caltech (January 1953)
The Moon and the Planets, Radio Astronomy, E&S, 16(4):9.
Caltech (December 1953)
The Month: Success, E&S, 17(3):24.
Caltech (November 1955)
Research Highlights: Astronomy, E&S, 19(2):16.
Caltech (May 1956)
The Month at Caltech: Radio Astronomy, E&S, 19(8):22.
Caltech (October 1958)
Listening to the Stars, E&S, 22(1):17.
Caltech (April 1959)
Color in the Universe, E&S, 22(7):26.
Caltech (January 1961)
The First True Radio Stars, E&S, 24(4):18.
Caltech (May 1966)
Palomar Gets a New Telescope, E&S, 29(8):9.
Caltech (November 1969)
Research Notes: Counting Photons, E&S, 33(2):42.
Caltech (January 1970)
The Month at Caltech: Change of Name, E&S, 33(3):32.
Caltech (November 1970)
A New Telescope at Palomar, E&S, 34(2):10.
Caltech (January 1973)
Electronic Revolution at Palomar, E&S, 36(3):20.
Caltech (September 1982)
Palomar's Future: Too Bright?, E&S, 46(1):18.
Caltech (Fall 1987)
Random Walk: Astronomy Gift, E&S, 51(1):43.
Caltech (Winter 1991)
First Lights, E&S, 54(2):2.
Caltech (Spring 1994)
The Owens Valley Radio Observatory: Early Years, E&S, 57(3):8.
Lab Notes: One Down, Six to Go, E&S, 59(1):39.
Palomar at 50, E&S, 61(3):31.
Random Walk: Caltech Joins Effort to Put Astronomy in Focus, E&S, 62(3):8.
R. Florence (1994)
The Perfect Machine,
HarperPerennial, 121–125, 240–242, 281, 286–291, 312, 340, 367, 397–398, 430.
O. Gage (June 1936)
The 200-inch Telescope Eye, JRASC, 30:169.
J. Gunn et al (March 1984)
A Large-Format, High-Efficiency CCD Camera for the Hale Telescope, BAAS, 16:477.
J. Gunn, E. Emory, F. Harris, & B. Oke (June 1987) The Palomar Observatory CCD Camera, PASP, 99:518.
J. Gunn et al (August 1987)
Four-Shooter: A Large Format Charge-Coupled-Device Camera for the Hale Telescope, OptEn, 26:779.
J. Greenstein & M. Schmidt (July 1964) The Quasi-stellar Radio Sources 3C 48 and 3C 273, ApJ, 140:1.
J. Gunn & J. Westphal (January 1981)
Care, Feeding, And Use Of Charge-Coupled Device (CCD) Imagers at Palomar Observatory, SPIE, 290:16.
E. Hoge (May 1949)
The 200-inch Telescope Takes Its First Pictures, E&S, 12(8):3.
C. van Houten, I. van Houten-Groeneveld, P. Herget, & T. Gehrels (October 1970) The Palomar–Leiden Survey of Faint Minor Planets, A&AS, 2:339.
I. van Houten-Groeneveld, C. van Houten, M. Wisse-Schouten, C. Bardwell, & T. Gehrels (October 1989) The 1977 Palomar–Leiden Trojan Survey, A&A, 224:299.
C. van Houten, P. Herget, & B. Marsden (July 1984) The Palomar-Leiden Survey of Faint Minor Planets: Conclusion, Icarus, 59:1.
C. van Houten, I. van Houten-Groeneveld, M. Wisse-Schouten, C. Bardwell, D. Green, & T. Gehrels (June 1991) The Second Palomar-Leiden Trojan Survey, Icarus, 91:326.
E. Helin, S. Pravdo, D. Rabinowitz, & K. Lawrence (May 1997)
Near-Earth Asteroid Tracking (NEAT) Program, NYASA, 822:6.
M. Hicks, R. Bambery, K. Lawrence, & P. Kollipara (June 2007) Near-Nucleus Photometry of Comets Using Archived NEAT Data, Icarus, 188:457.
M. Humason & H. Gates (June 1960)
The 1959 Palomar Supernova Search, PASP, 72:208.
60-inch mirror blank images.
Dedication of the 60-inch telescope images.
E. Helin & E. Shoemaker (December 1979) The Palomar Planet-Crossing Asteroid Survey, 1973-1978, Icarus, 40:321.
E. Herzog, P. Wild, & F. Zwicky (October 1957)
A New Catalogue of Bright Galaxies and Clusters of Galaxies, PASP, 69:409.
E. Herzog & F. Zwicky (June 1951)
The Palomar Search for Novae and the Light-Curves of Three Novae of 1950 in Scorpius, PASP, 63:121.
IrAJ (December 1951) News and Comments: A Systematic Search for Novae, IrAJ, 1:240.
iPTF Collaboration website.
JPL (April 2001)
NASA to Track More Asteroids with New NEAT Camera, press release.
T. Koenig (December 2005)
Fritz Zwicky: Novae Become Supernovae, ASPC, 342:53.
S. Kardel (2005)
Untwinkle, Untwinkle, Laser Star, E&S, 68(3):8.
S. Kulkarni (February 2013)
Intermediate Palomar Transient Factory (iPTF) Begins, ATel #4807.
C. Kowal, J. Huchra, & W. Sargent (August 1976)
The 1975 Palomar Supernova Search, PASP, 88:521.
B. Lasker, C. Sturch, B. McLean, J. Russell, H. Jenkner, & M. Shara, (June 1990) The Guide Star Catalog. I – Astronomical Foundations and Image Processing, AJ, 99:2019.
K. Lawrence et al (September 2008)
Preliminary Photometric Results Obtained from the NEAT Archive, DPS, 40:2809.
R. Laher et al (July 2014)
IPAC Image Processing and Data Archiving for the Palomar Transient Factory, PASP, 126:674.
W. Luyten (1974) The Palomar Proper Motion Survey, IAUS, 61:169.
C.S. McDowell (September 1935) Progress Memorandum, Caltech Archives.
C.S. McDowell (January 1939) Final Report on the 200-inch Telescope Project, Caltech Archives.
J.E. Mueller (July 2015) personal communication.
T. Mitchell et al (July 2000)
Palomar Adaptive Optics Project: Status and Performance, SPIE, 4007:31.
Nature (July 1949)
News: Sky Survey by the Schmidt Telescope at Palomar, Nature, 164:97.
NEAT on the web: JPL's NEO,
old NEAT website.
D. Osterbrock (June 2003) Don Hendrix, Master Mount Wilson and Palomar Observatories Optician, JAHH, 6:1.
S. Pravdo, E. Helin, M. Hicks, & K. Lawrence (November 2001)
Asteroid Tracking at Palomar and Maui, DPS, 33:5901.
M. Postman et al (February 1996) The Palomar Distant Clusters Survey. I. The Cluster Catalog, AJ, 111:615.
Palomar Observatory/Froebel Collection, Westinghouse images.
Palomar Observatory, 60-inch telescope first logbook.
W. Sargent The Second Palomar Observatory Sky Survey (POSS II).
All Palomar Supernova Search papers.
QUEST on the web:
The Palomar-QUEST Sky Survey,
The QUEST Camera
R. Richardson (December 1947) The 200-inch Mirror Goes to Palomar Mountain, PASP, 59:310.
I. Reid et al (July 1991)
The Second Palomar Sky Survey, PASP, 103:661.
I. Reid & G. Djorgovski (January 1993) The Second Palomar Sky Survey, ASPC, 43:125.
Robo-AO Collaboration website.
A. Sandage (May 1958) Current Problems in the Extragalactic Distance Scale, ApJ, 127:513.
A. Sandage (1961) The Hubble Atlas of Galaxies, Carnegie Institution of Washington, 18.
C. Shoemaker (February 1996) Twelve Years on the Palomar 18-inch Schmidt, JRASC, 90:18.
A. Sandage (September 1999)
The First 50 Years at Palomar (1949–1999).
The Early Years of Stellar Evolution, Cosmology, and High-Energy Astrophysics, ARA&A, 37:445.
See also same content as a website. A. Sandage (2004)
Centennial History of the Carnegie Institution of Washington: Volume 1, 387.
D. Smith (November 2006)
Picture This, E&S, 69(4):20.
R. Scalzo p. Nugent, C. Baltay, G. Djorgovski, Palomar-Quest Survey Team, & DeepSky Collaboration (January 2009)
The Palomar/QUEST-DeepSky RG-610 Variability Survey, BAAS, 41:258.
L. Schmadel, R. Stoss, & G. Burkhardt (October 2007) Digitization of the Palomar–Leiden Survey and Trojan Survey Plates, ASPC, 377:294.
STScI (29 November 1995)
First Clear Evidence of a Brown Dwarf.
P. Wild (April 1960)
of the Supernovae of 1954, PASP, 72:97.
G. Wallerstein & B. Oke (September 2000)
The First 50 Years at Palomar (1949–1999).
Another View: Instruments, Spectroscopy and Spectrophotometry, and the Infrared, ARA&A, 38:79.
F. Zwicky (May 1937)
On a New Cluster of Nebulae in Pisces, PNAS, 23:251.
F. Zwicky (August 1938)
the Clustering of Nebulae, PASP, 50:218.
F. Zwicky (October 1950)
Cancer Cluster of Galaxies PASP, 62:196.
F. Zwicky (November 1959)
Search for Supernovae E&S, 23(2):24 .
F. Zwicky (February 1964)
Results of the International Search for Supernovae, AnAp, 27:300.
F. Zwicky (1965) The Early History of the Faint Blue Star Program, First Conference on Faint Blue Stars (Aug 1964), 3.
F. Zwicky (December 1965) The 1964 Palomar Supernova Search, PASP, 77:456.
F. Zwicky (May 1973)
100 Supernovae—The Reward of a 40-Year Search, E&S, 36(6):20.
F. Zwicky, J. Berger, H. S. Gates, & K. Rudnicki (June 1963) The 1962 Palomar Supernova Search, PASP, 75:236.