February 5th
this week will mark the date when Mariner 10 became the first
spacecraft ever to test out and execute a technique known as a
planetary gravity assisted flyby used to alter its speed and
trajectory- in order to reach another celestial body.
Mariner 10 flew by
Venus 45 years ago to enable the probe to gain enough speed and alter
its flight path to eventually become humanity’s first spacecraft to
reach the planet Mercury, closest to our sun.
It was the first
spacecraft to visit two planets.
From that moment on,
gravity assisted slingshot maneuvers became an extremely important
technique used numerous times by NASA to carry out planetary
exploration missions that would not otherwise have been possible.
The Mariner 10 probe
used an ultraviolet filter in its imaging system to bring out details
in the Venusian clouds which are otherwise featureless to the human
eye – as you’ll notice when viewing it through a telescope.
Venus’s surface is completely obscured by a thick layer of carbon dioxide clouds.
The hellish planet’s surface temperature is 460 degrees Celsius
or 900 degrees Fahrenheit.
Following the
completely successful Venus flyby, Mariner 10 eventually went on to
conduct a trio of flyby’s of Mercury in 1974 and 1975.
It imaged nearly half of the planet’s moon-like surface, found surprising evidence of a magnetic field, discovered that a metallic core comprised nearly 80 percent of the planet’s mass, and measured temperatures ranging from 187°C on the dayside to minus 183°C on the nightside.
Mercury was not
visited again for over three decades until NASA’s MESSENGER flew by
and eventually orbited the planet.
Mariner 10 was
launched on Nov. 3, 1973 from the Kennedy Space Center atop an
Atlas-Centaur rocket.
Shortly after
blastoff if also took photos of the Earth and the Moon.
Ultimately it was
the last of NASA’s venerable Mariner planetary missions hailing
from the dawn of the Space Age.
Mariner 11 and 12
were descoped due to congressional budget cuts and eventually renamed
as Voyager 1 and 2.
Source: https://www.universetoday.com/109035/mariner-10-best-venus-image-and-1st-ever-planetary-gravity-assist-40-years-ago-today/