PROJECT BLUE BOOK

.
1. DATE 2. LOCATION 12. CONCLUSIONS
11 May 52 Seattle, Washington Was Balloon
o Probobly Balloon
3. DATE-TIME GROUP 4. TYPE OF OBSERVATION D Possibly Bolloon
Locol 0120 PST Ground-Visual Ground-Radar o Was Aircraft
o Probably Aircraft
Air Visuol Air-Intercept Radar D Possibly Aircraft
5. PHOTOS . SOURCE I3 Was Astronomical METEOR
D Yes 00 Probably Astronomical
No Many . Possibly Astronomical I
7. LENGTH OF OBSERVATION 8. NUMBER OF OBJECTS COURSE Other
1 o Insufficient Data for Evaluation
D Unknown
0. BRIEF SUMMARY OF SIGHTING 11. COMMENTS
Vivi blue. Sphere w/tail. Steep dive. See
Two astronomers said it was a meteorite. Ma ATT Actos Diree

ject may have eluded the radar.
Bennett said that the angle, rath-
er than speed, probably was what
caused it not to show as a "bllp"
on the radar scopes. :.
"If it was a meteor, it was -
probably coming nearly straight
down. That would make it very
difficult to track. The indica-
tions might be so insignificant
that radar wouldn't pick it up,"
he said.
"If it was an aircraft or a
guided missile, we would have
picked it up," he continued.
Many believed, after the blast,
onfinued on Page 2 Column

to have been inflicted on the people's nerves.
Ly 11.-(UP) A.30-second rumble followed the
ceel' industry breaking apart of the celestial It was a blue-white magnesium
rguments be- visitor into an cstimated four to color," they reported over the po-
rt tomorrow 10 large pieces. lice radio. "It lit up the sky like
'onstitutional chain lightning."
resident Tru- Altitude Estimated switch-
rity to seize Newspaper police
Witnesses found it difficult to boards were jammed byexcited -
estimate the object's altitude and callers whose fear anged from
will contend Ispeed, but triangulation fixed the
ample power explosion point somewhere over o earthquake. Very few thought of
April 8 to just north of Greenlake in north meteor.
strike by the central Seattle. a
iteelworkers. The Coast Guard estimated from Police and state patroimen pa-
iter that the early reports that it might have trols made fruitless efforts to
itutional au- been as low as 2,0o0 feet when it find pieces of the meteor.
to seize its burst. However, Capt. Bert Cari-
son, a Northwest Airlines pilo.
finds acting said it appeared to be only a littie IX
lip B. Perl- below his altitude of 8.0o feet.
r Baltimore, Carlson n said he was flying EBINS
B
1
1

LAS
RAW
..
Cool, damp breezes- :
Watch out for sneezes The Detroit Free
Offielal U. S. Weather Map on Paxe 25
SUNDAY TEMPERATURES
7 a.m. 44 a.na. iR 1 p.m. 58 p.m. 58 7 p.m. 56
9 a.m. 48 SIM p.m. 59 8 9 p.m. 34 p.m. 52
10 a.63. 51 a.m. 49 D.D. 55 p.m.57 10 p.m. 50 11 p.m. 48
1 13008 53 p.m. 53 12 mid. 47 MONDAY, MAY 12, 1952 On Guard for Over a Century 40 Pages
-
Was Eerie Explosion a Meteor?
SKY BLAST ROCKS
SKYE BLAST
11
Free Press Wire Services Free Press Wire Services at a height estimated as low at a height estimated as low ever, that it might have 7,000 feet when it suddenly 7,000 feet when it suddenly was inclined to was inclined to doubt that the doubt that the found, Kuip
SEATTLE - An unidenti- as 2,000 feet. been higher than reported shattered into eight pieces object exploded even as low cause they
+ fied missile-possibly a giant .** by observers.. which looked like chain light- as 7,000 feet. reaching g.
meteor - "rum bled like a THOUSANDS persons ning. What appeared to be "Fireballs usually explode they are
freight train" across the sky were awakened by the con- Dr. Fred L. Whipple, fireballs trailed to the earth, noticed.
Harvard Uniyersity meteor 10 to 15 miles up," he said.
and exploded over Seattle cussion, but there was no re- he said. "However, anything can The cha
early Sunday. port of damage. expert, said that if the Wash- * * * or a large
The Air Defense Command The phenomenon was at ington blast had been a little AN ASTROMONER at the happen, and the reported one striki
began an immediate investi- first definitely believed to be lower than reported it might Yerkes Observatory, Lake force of the explosion sug- "extremely
gation. caused by a meteor exploding have wiped out all of Seattle Geneva, Wis., said the Seattle gests that it was somewhat said.
The explosion bathed this and its inhabitants. lower than the usual height. The fam
within the earth's atmosphere. phenomenon apparently was a * * **
industrial city of 500,000 But astromoners said it Northwest Airlines Pilot "fireball" - a big meteor zona is ver.
persons in an eerie blue-white was almost impossible for a Bert Carlson sighted the ob- heavy enough to penetrate "METEORS' surfaces burn recent site
light and knocked city dwell- meteor to get within 2,000 ject as he prepared to land at into the earth's lower atmos- off rapidly from friction with Canada api
ers from their beds. feet of the ground before dis- Seattle-Tacoma international phere. the air and they often explode before the:
The blast was visible from integrating. airport. But the Yerkes expert, from the tremendous heat." J. Hugh
60 miles away, and occurred Some pointed out, how- He said it was at about Prof. Gerard Kuiper, said he Fragments are seldom gional direc
.

= r.
.
.
METRO FINAL
.
Detroit Free Press WE VISIT ADRIAN
Reporter Louis Cook Tells
About Bustling City,
with Pictures by
On Guard for Over a Century 40 Pages Vol. 122—No. 7 Five Cents Doug Kennedy
--
losion a Meteor? 4
.
ST ROCKS SEATTLE
ROCKS SEATTLE
might have 7,000 feet when it suddenly was inclined to doubt that the found, Kuiper said, either be- can Meteor Society, said: Everything turned blue.
a2 reported shattered into eight pieces object exploded even as low cause they burn up before Unless it was an infernal As soon as it went out there
which looked like chain light- as 7,000 feet. reaching ground or because machine of some kind, it could were fireballs or something
ning. What appeared to be "Fireballs usually explode they are too small to be have been a huge meteor." falling straight down like
Whipple, fireballs trailed to the earth, 10 to 15 miles up," he said. E noticed. fireworks. That camne in an-
rsity meteor The chances of a meteor * * * other couple of seconds.
if the Wash- he said. "However, anything can
* * *. or a large fragment from THREE SEATTLE police Two or three minutes later
been a little AN ASTROMONER at the happen, and the reported one striking the earth are prowl cars reported the ob- I heard the rumble."
rted it might Yerkes Observatory, Lake force of the explosion sug- extremely rare," Kuiper ject exploded over Green Lake
all of Seattle Geneva, Wis., said the Seattle gests that it was somewhat said. in North Seattle at about Most observers agreed the
nts. phenomenon apparently was a lower than the usual height. The famed crater in Ari- 2,000 feet. object was travelling from
irlines Pilot fireball" - a big meteor * * * zona is very old, he said, and Sidney Howick, weather southwest to northeast when
hted the ob- heavy enough to penetrate "METEORS' surfaces burn recent sites discovered in observer at the Seattle- t blew up.
red to land at into the earth's lower atmos- off rapidly from friction with Canada appear to date from Tacoma airport weather bu- Ten hours after the ex-
international phere. the air and they often explode before the Ice Age. reau, said: "It was sort of a plosion, there were no reports
But the Yerkes expert, from the tremendous heat." J. Hugh Pruett, Pacific re- lights-on, lights-off thing. It of damage or recovered frag-
yas at about Prof. Gerard Kuiper, said he Fragments are seldom gional director of the Ameri- lasted two seconds at most. ments.

TO: Chief, Air Wechmicel Intelligence Conter
Wright-Patterson Air Force Base
Dayton, Ohio .
dated 11 April 1951.
2. If inclosure is vithdravn or not ottached, the
correspondence vill be downgraded to "Uncles:ified", in clessificction of this
paregraph 25c, AR 205-1. nocordance with
FOR THE LCER:
1 Inel MARY ROTHER
Info on Unconventionel Acft, 2nd Lt USAF
dtd 16 Adjutant General
Distribution:
i
W
UNCLASSIFIED .
1003339 3712-48

feel exlosion.
also sev lieved it ex lodod in the Renton
aree. Washiegton State P
Tower were aonget penple Siti7 Diec
t re ort roccived
tho rooortel the
anl severel
neumes of people slgiting the ob joot becuuse of the volule of etl' e. r
(Gase Oerator) rejortod secing the obieot. in.
Neil ao Vcobegh
MEIL A VOSEURGH
MeJor US.AP
Direotor of Intelligonce
DOWNGRADED AT S YEAR INTERVALD
DECLASSIFIED AFTER 12 YEARS.
DOD DIR 5200.10
UNCLASSIFIES
MOTE: THIS DOCUMENT CONTAINS INFORMATION AFFECTING THE NATIONAL DEFENSE OF THE UNITED STATES WITHIN THE MEANING OF T THE ESPIONAGE ACT, 5O U. S. C.-
31 AND 32. AS AMENDED. ITS TRANSMISSION OR THE REVELATION OP ITS CONTENTS IN ANY MANNER TO AN UNAUTHORIZED PERSON IS PROHIBITED BY LAW.
IT MAY NOT BE REPRODUCED IN WHOLE OR IN PART, B OTHE FORCEACENCIES EXC BY PERMISSION OF THE DIRECTOR OF
INTELLIGENCE, USAF.
OPPIcS
- .

b. Pime of sigting: aoroxinatoly 0132 P801fic St:niord
Tine, 11 Hay lesa. P.riod of darntion: soconds.
c. Not sic
Northwest Airlines pilot sigitod ob,jeot at oooo fcot
2 ndnutes before Daesing Hobart Fen irker at Olgl or Olue Pecific Stonlerd
Seattle-Tacons lending at
Air bort at ?ooo feet on course due west. Aproxin te Dosition
of exolcsion 400al"ll and 132°12"W. Mr Soattle cngineer,
about 21 degrees above horlzon and i3 degrees cust of north.
e.
h. Mo phyeicel
-
i.
Duretion of
1 INCLS.
Clipping Mon Soat le Post I Intol igencer
atd 1s 1ky 1952
DOWNGRADED AT S YEAR INTERVA
DECLASSIFIED AFTER 12 YEAR.
DOD DIR 5200.10
DISTRIBUTION BY ORIGINATOR
Dir of Intell, Dso/o, Ho US.F 1 cy
CG AWe Attn: Dir of Intell I cy
Ce WL) Attn: Dir of Intoll 1 ct
MOTD THIS DOCUMENT CONTAINS INFORMATION AFFECTING THE NATIONAL DEFENSE OF THE UNITED STATES WITHIN MEANING OF THE ESPIONAGE ACT. 50 U. S. C.—
31 AND 32, AS AMENDED. ITS TRANSMISSION OR THE REVELATION OF ITS CONTENTS IN ANY MANNER TO AN UNAUTHORIZED PERSON IS PROHIBITED BY LAW.
IT MAY NOT BE REPRODUCED IN WHOLE OR IN PAR' OMOHINER THAN-UN MGENCIES.EXCEPH BY PERMISSION OF THE DIRECTOR OF
INTELLIGENCE, USAF.
(CLASSIFICATION) VERNMENT PRINTIN FICE :1950-O-918331
..
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SYMBOL TELEPHONE OFFICIAL TITLE RORERT B. KENMNDY, Major, USAF
54061 Ainjnt 1
REPLACES NME FORM 173, 1 MAY 49, 16-S923-3  U. 8. GOVERNNENT PRINTING OPFICE
173 WHICH MAY BE USED,

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. UNCLASSIFIED
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XYAZ57 (
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RR JEDWP
DE JWPDM 002G . -
ACTION
R 261730Z .
FM CG 25TH AIR DIV MC CCHORD AFB WASH UNCLAO.E
FOL ASTRONOMERS CONTACTED CLN DR AND DRFR UNIV
OF WASH CMA THEY STATE OBJECT WAS S A METEOR PD A SEARCH FOR FRAGMENTS
IS BEING CONDUCTED PD IF ANY ARE FOUND YOUR HQS S WILL BE NOTIFIED PD
26/1652Z MAY JWPDM .
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DECLASSIFIED AFTER 12 YEARS. DOD DIR 5200.10 .
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1
APPENDIX IV
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Seattle: Washington 11 May 1952
I. LESCRIPTION OF IICILEST
...
At approximately 0124 to 0132 PST, on 11 May 1952 many incividuels re-
ported sighting a viid blue object wi th flaminz sparks or streamers coring
nearly straight down over Seattle, Washington, The object ex-loded in a
brilliant flash, ligiting up the sky and disappeared. fter the molo-
sion, some of the wimesses experienced a shoc dimately
nine seconds duratior.
II. S STATUS OF THE 1
Two local astronners rere contacted and they stated that the object was
a meteor. At the prisent tire the as agmeats to
confirm their statennt. confirm their statemnt. .
III. CONCLUSIONS .
Object was probally afirming
evidence is found. eviderce is found. .
+ …. ..
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. DOWNGRADED AT S YEAR INTERVALS;
DECLASSIFIED AFTER 12 YEARS.
DOD DIR 5200.10
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T52-11949 16
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II .
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J. T. Skelly, 7125-44th Ave.
S. W., who described the rumble
6 that followed the flash as a "five-
shock wave that shook my house."
SAW FLASH-
From the window of his Mercer
Island home, Guy L. 1 Bettinger,
. 7424 W. Mercer Way, saw what
he described as a "tremendous
flash in the sky." He said:
"The light to go
straight up, like age electric
arc-something lik when a.
transformer explodes. The
apex of the ligh emed to be
deep, shaking tremor which last-
ed 12 seconds, The tremor start-
ed 21 minutes after the flash.
This would put the explosion 30
or 31 miles away. The flash was
21 degrees above the horizon and
18 degrees east of north.
"The tremor had a deep.
deep sound like somehody down
In the furnace," Lyman said.
.

CHECKING DATA-
As eyewitness accounts of the .
LINE OF FLIGHT -ShOWn on this mop is the path h and the burating strange light and following blast
point of the nerinl objeet that flashed over Western Washington carly came in from widely scattered
Sunday. As the map shows, the objeet, apparently meteor, traveled parts estern Washington,
from south to north and burst into fragments at the point indicated astronomers oressed the opin-
on. the map. Position was determined by eyewitness reports from an lon that an unusually big fireball
airliner and various ground observers. After burating. fragments of the had been destroyed aloft in
object traveled to the northwest into an aren not covered by the map. spectacular manner.
Dotted lines and arrows indicate direction of sight of eyewitnesses who Col. Allan Bennett. com-
established approximate location of the burst.. manding officer of the 25th Air
-(Pust-Intelligeneer Map.)
Force Defense Division, McChord
Air Force Base, also leaned
toward the theory that the object
which exploded at 1:26'a. m. was
a meteor. But he sald his office
oh
MeChord.
Bennett said that the ground
observer phase of the air defense
setup is not at present on a 24.
hour basis, and said no ground
observers had reported seeing
the flash. T
The two-second blast, a tremen-
dous blue-white flare, caused no
ascertainable damage, but police,
fire department and newspaper .
switchboards were jammed by
hundreds of anxious. calls from
suddenly-awakened persons.