UFOs

Karen J. Meech, Astronomer

Institute for Astronomy

"The heavens call to you, and circle about you, displaying to you their eternal

splendors, and your eye gazes only to earth.”

Dante, 1300

What Are UFOs?

!  UFO Definition !  U = Unidentified !  F = Flying !  O = Object

!  Each day there are 1-2 sightings in the US

!  What are they? !  Real phenomena !  Natural in origin? !  Alien visitations?

My Position !  There is life elsewhere

!  It is not coming to Earth in flying saucers

!  IF UFOs are extraterrestrial !  And They want to be seen

!  Why are there so few sitings? !  Why is there no physical

evidence? !  And They don’t want to be seen

!  Why are any seen " technologically advanced!

Public Interest

Phenomena Beginnings

!  June 24, 1947 Incident !  Private pilot Kenneth Arnold – Mt. Rainier WA !  9 circular objects flying !  Diagonal formation !  Rapid flight – “motion as if a saucer were

skipped on water” !  Political climate

!  WWII had just ended " cold war !  New technology – rocketry

!  Reports suddenly escalated !  “Mysterious celestial objects have always

been around " interpret according to contemporary context”

Skepticism – Allen Hynek

!  Investigations must be thorough !  Similar to criminal investigation !  Never enough $ or people for this

!  Incidents are usually real phenomena !  People report the same thing

!  Consider Witness reliability

!  Project Blue Book (1952) !  AF investigation of UFO

phenomena – 21 yrs !  Investigated 12,600 events

(701 or 6% unsolved) !  1968 Condon Report:

USAF " not ET !  1969 closed: files open !  1976 " National archives

(80,000 pages)

Witnesses

!  Humans aren’t computers " interpretation !  Memory is biased

!  Wishes / desires !  Prejudices !  Experience /ability " shaping a report to fit ideas

!  Environment !  Poor recall under stress !  Influenced by physical state

!  Passage of Time !  Increase in detail over time for some things

original 3 months

“Sky Shock”

!  Distance vs Angular Size !  We can measure only !, not h or

d!!

!"

h d

!  Perception !  Zenith is closer than horizons !  Error in elevation angle

measurement!

Apparent shape of heavens

Observers call this 45o

It is not!

Sky Shock

!  Brightness !  Venus can be very bright !  Cleared for landing many times !  WWII ship tried to shoot it down

!  Parallax !  Apparent motion of nearby

objects !  “Aggressive” stars !  “Matching speed” !  “Following”

Sky Shock

!  Speed – only angular velocity !  Cannot estimate: h, d unknown !  Meteors: 70 km/s (156,000 mph) !  Airplanes – several 100 mph

!  Autokinesis !  Small jerking motion of eye !  Involuntary reflex !  Staring intently at bright source in

darkness !  Effect: Object appears to move

Rational Explanations Stars & Planets 360

Advertising planes 230 Aircraft 196 Meteors & satellite re-entry 113 Satellites 24 Moon 22 Weather balloon 22 Searchlights 11 Missile Launches 9 Birds & Kites 9 Clouds 8 Mirage & reflections 2

1007 IDs from 1024 reports Meteors

!  Historical perception !  Until the 1900’s: rocks cannot

fall from sky

!  Meteor must “fall” down to Earth !  We just view an arc through

atmosphere !  Depends on orbit direction !  Depends on time of day

A Meteor Example !  UFO report (1948, 1968)

!  Large craft !  Lighted windows

!  Resolution !  Break up of fireball

Rocket and Missile Launches !  Cause of many UFO reports

!  In S. America – USSR trajectories

!  Can often see a luminous rocket trail

!  Seen over large distances !  h = altitude !  RE = Earth’s radius = 6,378 km !  d = distance visible !  RE / (RE + h) = cos(!)

!  d = 2 # RE (!/360)

!  For h = 60 km d = 900 km

Noctilucent Clouds

!  Low T in upper atmosphere !  Some clouds form as high as

80 km (200K) !  High cirrus (ice crystals) !  Although on the dark side of

Earth, high altitude means they are still in sunlight

Lenticular Clouds !  Lens shaped clouds !  Form at high altitudes !  Form when stable moist

air flows over a mountain or range of mountains

Historical “UFO”

!  Complex crystal display – Parry arcs

Astronomical Objects

!  Image sent to IfA as a UFO over Mauna Kea

!  This is a crescent moon and Venus

Astronomical Objects?

!  Two supposed UFOs !  Appearance is identical to

badly tracked star images !  Luminous blob

!  Scattered light? !  Internal telescope / lens

reflection

What about the Photos? Why are the pictures so Bad?

!  Clearly we can take better pictures !  Shuttle Columbia just as entering Earth Atmosphere !  Drone aircraft at 25,000 ft (from War zone) !  Shuttle landing – amateur photo (telephoto) !  Advertising airplane (amateur photo)

Abductions – Betty & Barney Hill

!  Look Magazine article 10/4/1966 !  Abduction 9/19/61 !  “Lost time” syndrome !  Sparked flurry of abduction tales

Their Story !  12:00am white mtns New Hampshire 9/19/61 !  Followed by a “star-like object” !  Divert to smaller roads !  Large object stopped when they

did !  Next day

!  sister & compass (irradiation) !  nightmares

!  9/26/61 – NICAP !  12 hr interview !  Suggestion of abduction

!  12/63 – Psychiatrist visit !  Hypnosis !  “Star down below the moon,

lower left side, bigger object over this one”

!  1966 Look magazine interview

9/19/61 NH

10:30pm !  Moon alt: 19.9o

!  Saturn alt: 16.5o

12:00am !  Moon alt: 7.7o !  Saturn alt: 3.5o !  Moonset 12:54 am !  Saturn set 12:25 am

Explanations !  “Following” " parallax !  Misunderstood size !  “The object” " Jupiter (good

description) !  Time wrong – impossible to see at

3o elevation !  “Lost time” " deviations !  Other Factors

!  Night sky ignorance !  Function of compass !  Relationship stress !  Made a lot of $ on story

Hoaxes

!  Nov 5, 1975 – “Best alien abduction story” !  Arizona – group of hunters !  Bright light in sky !  Friends fled, Walton re-appeared 5 days later !  Many claim this was a hoax, many claim no !  " No solid evidence, only “stories”

Roswell – 1947 New Mexico

!  Military – weather balloon crash !  Others argue UFO

!  1966 piece " museum !  Composition Cu, Ag !  Sagan – meas isotopes

Earth Fragment 63Cu – 69.174% 63Cu – 69.123% 107Ag – 51.90% 107Ag – 51.84%

The Hoaxes

!  This image was sent to the IfA director’s office

!  Later admitted to be a hoax: a “pog” tossed out of a Waikiki hotel window

Summary

!  Sky Ignorance !  People are curious but lack

ability to interpret !  Witness caveats

!  Lack of investigation !  Most ignorant of scientific

process !  Psychology

!  Hoaxes

“Two possibilities exist: either we are alone in the Universe or we

are not. Both are equally terrifying.”

Arthur C. Clarke