Lombard, Illinois, May 21, 1952: the hot glass marble.
THINK ABOUTIT UFO|UAP SIGHTINGS REPORT
Lombard, Illinois: The Hot Glass Marble That Dented a Mailbox
At about 3:30 on the morning of May 21, 1952, a Lombard, Illinois, homeowner heard something pass over his house and then strike his steel mailbox with a bang. When he looked, he found a one-inch, glass-like sphere coated in black and reddish tar lying on his porch. He picked it up four minutes later and dropped it, because it was too hot to hold.
The Lombard, Illinois glass marble is one of Project Blue Book’s few recovered physical specimens: an object that fell out of the sky, dented a mailbox, steamed on a lawn and was shipped to Wright-Patterson Air Force Base for analysis. An F-86 had flown over only moments before.
Date: May 21, 1952
Sighting Time: 3:30 a.m. CDT (card: 0830 CST)
Day/Night: Night
Location: Lombard, Illinois (reported through the 4706th Defense Wing, O’Hare)
Urban or Rural: Urban / suburban
No. of Entity(‘s): Not Applicable
Entity Type: Not Applicable
Entity Description: Not Applicable
Hynek Classification: Not classified (a recovered physical specimen; the object was never seen in flight)
Duration: A few seconds of sound, then four minutes before recovery
No. of Object(s): 1
Description of the Object(s): A transparent, glass-like sphere about one inch in diameter, partly covered with a black and reddish material resembling tar or macadam; hot to the touch
Shape/Size/Color of Object(s): Sphere / about one inch / transparent with black-reddish coating
Distance to Object(s): Struck a mailbox on a partly closed porch
Height & Speed: Came from the south, heard passing overhead seconds before impact
Number of Witnesses: One homeowner (the owner of the house)
Special Features/Characteristics: Dented the rounded corner of the steel mailbox 3/16 inch, bounced to the porch, left a black line, steamed on the lawn; an F-86 had just flown over
Case Status: Explained: glass marble (physical specimen), per Blue Book
Source: Project Blue Book record card; 4706th Defense Wing teletype and Air Intelligence Information Report; ATIC analysis
Summary/Description: A tar-coated glass sphere, too hot to hold, dented a mailbox in Lombard, Illinois; ATIC concluded it was a marble.
Related Cases: None
Detailed Report
A teletype from the 4706th Defense Wing at O’Hare to ADC, ATIC and other headquarters reported “one spherical transparent glass-like object one inch in diameter, part covered with black and reddish material resembling tar or macadam,” which struck a mailbox in Lombard at about 0330 hours. It dented the rounded corner of the steel mailbox 3/16 inch and bounced to the porch, “leaving black line to point where owner of house picked it up four minutes later but dropped it due to its heat.” The position of the mailbox on a partially closed porch indicated the object came from the south; the homeowner heard it pass over a few seconds before the impact. The weather was clear with 12,000 feet broken and 25,000 broken, 2½ miles visibility in smoke, temperature 59, dew point 45, calm wind.
The Air Intelligence Information Report adds that the object was recovered after the homeowner dropped it on the lawn, where it steamed, forming a small steam-like cloud in the still air. It was forwarded to the Air Technical Intelligence Center under separate cover. The reporting officer noted that F-86s had flown their first flight since an Armed Forces Day display, and that aircraft compartments were examined for the possibility the object had been deposited in an aft section, with negative evidence. The object had not been analyzed or tested for radioactivity.
ATIC’s Technical Analysis Division concluded that the object had not traveled at any great speed for any distance, which would have melted and removed the coating, and that a high-velocity impact would have shattered the glass or driven it through the mailbox rather than merely denting it. Blue Book’s card read Other: glass marble, with the comment that it was a “known object, origin unknown,” which could have been thrown from a slingshot or kicked up by a truck.
RESEARCHER’S NOTES
A Physical Specimen With a Mundane Verdict
- Evaluation: Blue Book classed the object as a glass marble and the case as a physical specimen; the record card does not list it as a UFO sighting in the usual sense.
- The tar coating: ATIC reasoned the coating was still present because the marble had not traveled fast or far; the heat when picked up remains unexplained in the file.
- The F-86 flyover: A fighter had flown over just before, which is why the report reached the Air Force; no link between the jet and the marble was established.
- Time discrepancy: The teletype and report give 0330 CDT; the Blue Book card shows 0830 CST, which is the same moment in a different time zone.
- Value to the archive: The case shows how Blue Book handled recovered debris and why such items ended up in ATIC’s laboratory.
Lombard is a strange but resolved case: a marble that fell near a jet’s flight path, dented a mailbox and burned a homeowner’s fingers. It earns a place in the archive as a rare example of the Air Force collecting and testing a physical object from an incident, and of the way Blue Book closed it.
“ONE SPHERICAL TRANSPARENT GLASS-LIKE OBJ ONE IN IN DIAM, PART COVERED WITH BLACK AND REDDISH MAT RESEMBLING TAR OR MACADAM”
— 4706th Defense Wing teletype to ADC and ATIC, May 21, 1952
