An asteroid about as long as the Great Pyramid of Giza is tall made a "close" approach with Earth on Sunday (July 25), according to NASA calculations.

There is no worry that the space rock poses any threat to Earth, but NASA monitors such rocks to both learn more about the early solar system — asteroids are rocky fragments from that time — and because if their orbits were to change, the asteroid could pose a future risk to Earth.

On its closest approach, the near-Earth asteroid, called 2008 GO20, swung within 2.8 million miles (4.5 million kilometers) of our blue marble.

(The Great Pyramid of Giza stands at 450 feet, or 138 m, tall.) Any space rock larger than about 490 feet (150 m) across that is expected to make a shave with Earth within 4.6 million miles (7.5 million km) is considered a potentially hazardous asteroid (PHA); NASA's Center for Near Earth Object Studies monitors all PHAs.

4, 1901, when the asteroid swung to 806,856 miles (1.3 million km) of our planet, according to NASA records.

Its next closest flyby happened on July 31, 1935 at a distance of 1.15 million miles (1.85 million km) of Earth!

When it next flies by Earth, on July 24, 20342008 GO20 was expected to get as close as 3.1 million miles (5 million km).