Astronomers use many methods to determine this number, including gravitational lensing, the universe’s expansion rate, and more.

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Mars and Spica will appear in close proximity (2° separation) in the evening western sky shortly after sunset, setting before 9 PM local daylight time. Observations of Mars and Spica are best ...

Luna 2, launched by the Soviet Union in September 1959, achieved the first human-made object impact on a celestial body other than Earth (the Moon). The mission's journey to the Moon lasted ...

Equuleus, also known as the Foal, is a small and faint constellation located southwest of Pegasus. Unlike many constellations, Equuleus lacks bright stars, nearby stars, prominent meteor showers, or ...

Saturn, at magnitude 0.6 in Pisces, is observable in the southeast at approximately 30° altitude. Titan, Saturn's largest moon, undergoes an occultation behind Saturn, beginning around 11:10 P.M. EDT ...

The International Sun-Earth Explorer-3 (ISEE-3) mission, a joint NASA-ESA endeavor launched in 1978, initially studied the solar wind and Earth's magnetic field from the L1 Lagrange point. Following ...

Amateur astronomers hold differing views on the significance of observing awards, with some actively pursuing them while others show little interest. The Herschel 400 observing program is frequently ...

Yevgeny Khrunov, born September 10, 1933, was selected as one of the first Soviet cosmonauts in February 1960. He participated in the Soyuz 4/Soyuz 5 mission in January 1969, which involved the first ...

Venus, currently traversing Leo, rises around 4:00 A.M. local daylight time (LDT) at 40° N 90° W, preceding sunrise at 6:36 A.M. LDT. By 5:30 A.M. LDT, Venus reaches 15° altitude in the east, with ...

A 250-day experiment using a ring laser achieved unprecedented accuracy in measuring Earth's axial wobble (nutation and precession), surpassing previous gyroscope and ring laser technologies by a ...

Fomalhaut (Alpha Piscis Austrini), a magnitude 1.2 star, is visible in the southern sky after 8:30 PM local daylight time, reaching its highest point around midnight. Located 25 light-years from Earth ...