Beyond Earth History Blog

Mariner 10. The last of Mariners Artist's rendering of NASA's Mariner 10 spacecraft. Credit: NASA/JPL-Caltech In 1969, NASA approved a plan to send a spacecraft to Mercury in 1973, using Venus for a gravity assist. The mission, managed by the Jet Propulsion Laboratory (JPL) in Pasadena, California, became Mariner 10. It was the last in the highly successful Mariner series of planetary spacecraft that revealed many secrets about the inner solar system. Using gravity assist, a technique theorized for decades but never used before, under favorable conditions a spacecraft sent to one planet can use that planet’s gravitational force to essentially slingshot on to its next target. The method saved the cost of additional fuel and a larger rocket that would be necessary to launch the heavier spacecraft as well as time to get to the ultimate destination.     Mariner 10 was the first spacecraft to use this technique to reach another planet. Its orbit was determined by Italian scien...

 Great Comet of 1577   The Great Comet of 1577, seen over Prague on November 12, 1577. In addition to the comet, five zodiac symbols appear in the sky: (L-R) Aries, Pisces, Aquarius, Capricorn, and Sagittarius. Below the comet's tail are the crescent moon and Saturn, depicted as a star with the astronomical symbol ♄. At the bottom center, a man draws the comet by the light of a lantern. Engraving made by Jiri Daschitzky. Credit: Wikimedia Commons The Great Comet of 1577 (C/1577 V1), one of the most important comets in the history of astronomy, was discovered in early November 1577. It was the first comet for which its location outside Earth's atmosphere was conclusively proven. The date of its first observations is uncertain. The comet could be first sighted in Peru on November 1 at dusk (November 2 UT), and in Mexico on November 4 or 6. On November 8, the Japanese recorded it as being as bright as the Moon and with a curved white tail stretching 50º. The glorious form of the ...

 Gaspra, the first asteroid encounter Visualization of the Galileo spacecraft as it flies past Gaspra. Credit: NASA/Andrzej Mirecki Galileo spacecraft, en route to Jupiter, flew by the asteroid (951) Gaspra at 22:36:46 UTC on October 29, 1991. The closest approach was 1,601 km,  and the relative speed was about 8 kilometers per second.  It was the first ever asteroid encounter by a spacecraft. In all, 57 images of Gaspra were taken by Galileo's SSI camera, covering about 80% of the asteroid, the closest taken from a distance of 5,300 km. The best images have a resolution of 54 meters per pixel.    The objectives of the encounter included determining the size, shape, cratering characteristics, and composition of the asteroid, as well as surveying the surrounding environment. Due to the failure of the spacecraft's main antenna, the results of the observations were recorded on the magnetic tape of the on-board recorder and most of images taken were not transmitted ...

 (69230) Hermes   The recovery image of asteroid Hermes by Brian Skiff using the LONEOS 59-cm Schmidt telescope on October 15, 2003.  Credit: Brian A. Skiff, Lowell Observatory Asteroid (69230) Hermes was discovered by German astronomer Karl Reinmuth (1892–1979) at Heidelberg Observatory on October 28, 1937. Only four days of observations could be made before the asteroid became too faint to be seen in the telescopes. This was not enough to calculate an orbit, and Hermes became a lost asteroid. It thus did not receive a number — only the provisional designation 1937 UB — but Reinmuth nevertheless named it after the Greek god Hermes. On October 15, 2003, Brian A. Skiff of the LONEOS project in Lowell Observatory in Flagstaff, Arizona, made an asteroid observation that, when the orbit was calculated backwards in time (by Timothy B. Spahr, Steven Chesley and Paul Chodas), turned out to be a rediscovery of Hermes. The asteroid has been assigned sequential number 69230.  ...

STEREO  Solar Terrestrial Relations Observatory Mission     Artist's concept of one of the STEREO spacecraft in orbit around the Sun. Credit: NASA STEREO (Solar TErrestrial RElations Observatory) is the third mission in NASA's Solar Terrestrial Probes program (STP). It employs two nearly identical space-based observatories – one lagging, the other leading the Earth in heliocentric orbit around the Sun – to provide the first-ever stereoscopic measurements to study the Sun and the nature of its coronal mass ejections, or CMEs. These events are responsible for large solar energetic particle events in interplanetary space and are the primary cause of major geomagnetic storms at Earth.     The two spacecraft were launched to drift slowly away from the Earth in opposite directions at about 10 degrees per year for the lagging spacecraft and 20 degrees per year for the leading one. Optimal longitudinal separation of about sixty degrees was achieved after two years....

Sputnik 2 The first animal in or bit Laika, confined in her mock capsule Following the enormous propaganda success of the launch of Sputnik on October 4, 1957, Soviet leader Nikita Khrushchev (1894–1971) approached Sergei Korolev (1907–1966), chief designer of the Soviet space program at Design Bureau No. 1 (OKB-1), with a request to conduct another space flight to commemorate the 40th anniversary of the Bolshevik Revolution, which was celebrated on November 7. At the time, OKB-1 was working on a large research satellite codenamed Object D, but it could not be ready in time. Object D was later launched as Sputnik 3 in May 1958.    In response to Khrushchev's request, Korolev proposed sending a dog into orbit. Dogs had been launched by the Soviets on suborbital flights in high-altitude research rockets since 1951, to study the effects of rocket flight and weightlessness, and preliminary studies for an orbital flight of a dog had already been discussed. The Presidium of the Cen...

 Iapetus (Saturn VIII)        Natural-color image of Iapetus. The view was obtained by the Cassini spacecraft narrow-angle camera on March 27, 2015 at a distance of approximately 1 million kilometers from Iapetus. Image scale on Iapetus is about 6 kilometers. Images taken using red, green and blue spectral filters were combined to create this natural-color view. The moon's brightness has been enhanced in order to make the dark terrain visible. The image also was enlarged by a factor of two compared to the original data. The large basin at lower right, within the dark terrain, is named Turgis. The slightly smaller crater at the nine o'clock position is Falsaron. The two prominent craters just above image center are Roland and Turpin. At the limb around the three o'clock position is the darkened rim of the crater Naimon.  Credit: NASA/JPL-Caltech/Space Science Institute Iapetus (Saturn VIII), a moon of Saturn, was discovered by Giovanni Domenico Cassini (1625...