History Today: How archaeologists found the world’s largest dinosaur fossil

One of the biggest dinosaur fossils, the complete remains of a Tyrannosaurus rex, was found in South Dakota on August 12, 1990. Found in the Hell Creek Formation of South Dakota’s Cheyenne River Indian Reservation, this specimen is recognised as the largest and most intact T. rex skeleton ever unearthed.

If you are a history geek who loves to learn about important events from the past, Firstpost Explainers’ ongoing series, History Today , will be your one-stop destination to explore key events.

IBM’s personal computer 515 officially went on sale in retail stores on this day in 1981.

Here is all that happened on this day.

The largest dinosaur fossil was found

On this day in 1990, amateur fossil hunter Sue Hendrickson made one of the most significant paleontological discoveries ever recorded - the remarkably complete remains of a Tyrannosaurus rex which was later nicknamed ‘Sue.’ Found in the Hell Creek Formation of South Dakota’s Cheyenne River Indian Reservation, this specimen is recognised as the largest and most intact T. rex skeleton ever unearthed, with approximately 90 percent of the bones recovered.

Over the next 17 days, Hendrickson’s team, led by palaeontologist Peter Larson of the Black Hills Institute, carefully excavated more than 250 bones, revealing a specimen over 40 feet long and around 13 feet tall at the hips. Notably well preserved, Sue’s skull alone weighed over 600 pounds, presenting outstanding anatomical detail that would transform scientific understanding of the species.

More from Explainers

History Today: When construction on the Berlin Wall began in 1961 History Today: How Pakistan got its national flag

Scientific analysis of Sue’s remains revealed intriguing signs of trauma and disease. The skeleton bore healed rib fractures and jaw infections, indicating the dinosaur survived violent encounters before succumbing, potentially aggravated by illness. Another notable find was Sue’s wishbone (furcula), a feature that provides crucial evidence linking birds to theropod dinosaurs.

Sue’s discovery triggered a complex legal battle involving land ownership and tribal claims. In 1997, the fossil was ultimately sold at auction to the Field Museum in Chicago for over $8 million, where it became a major public attraction and continues to be a central subject of ongoing scientific research.

Editor’s Picks

1

What is the ‘dinosaur highway’ uncovered by scientists in England? 2

The 70-mn years old marine dinosaur turns out to be a fossil fraud

IBM personal computer was launched

The computing world was forever changed when IBM officially announced the launch of its first Personal Computer (PC), the Model 5150. The launch represented IBM’s entry into the consumer and small-business computer market, an arena then dominated by companies like Apple, Commodore, and Tandy.

Prior to the IBM PC, personal computers were often seen as toys for hobbyists, with machines like the Apple II and Commodore PET dominating the small, but growing, market. IBM, a company long synonymous with corporate mainframes, was a late but formidable entrant. The company’s decision to use an open architecture, relying on off-the-shelf components like an Intel processor and Microsoft’s MS-DOS operating system, was a radical departure from its traditional closed systems. This choice proved to be a masterstroke.

The announcement was a watershed moment because it bestowed a new level of legitimacy on the personal computer. IBM’s reputation and marketing power signalled that computers were no longer just for enthusiasts but were now serious tools for business and the home.

The availability of the computer in major retailers like Sears and ComputerLand, starting in September 1981, ensured it quickly reached a wide audience.

This Day, This Year

• In 1961, East Germany began construction of the Berlin Wall.

• Isaac Merrit Singer patented his sewing machine and formed I.M. Singer & Company to market the product on this day in 1851.