1) In Greek mythology, the Trojan War is a legendary conflict between the city of Troy and the Greeks, sparked by the abduction of Helen of Troy. It is immortalized in Homer's epic poems, the Iliad and the Odyssey, and features famous heroes like Achilles, Hector, and Odysseus.

2) The coldest known temperature in the universe was achieved in a laboratory in 2019, reaching a fraction of a degree above absolute zero (-273.15 degrees Celsius).

3) The development of the microprocessor by Intel in 1971 paved the way for the modern computer and led to the exponential growth of computing power.

4) The Great Rift Valley is a geological feature that stretches over 6,000 kilometers (3,700 miles) from Lebanon to Mozambique. It is known for its diverse landscapes, including deep lakes, volcanic mountains, and fertile valleys, and is considered a significant site for the study of Earth's tectonic activity.