MARS VIEWED IN ULTRAVIOLET: MAVEN’s Imaging Ultra-Violet Spectrograph took this image of Mars on July 13, 2016, when the planet appeared nearly
full, viewed from the highest altitudes in the MAVEN orbit. The ultraviolet colours of the planet are shown in false colour, to show what we would see with
U-V-sensitive eyes. North is up. The deep Valles Marineris canyon (centre of image) appears blue due to the scattering of ultraviolet light by the atmosphere,
which masks the canyon floor. The overall greenish tinge of is a combination of reflection from the surface and atmospheric scattering. The three tall Tharsis
volcanoes at left have white clouds forming as the winds flow over them. Bright white polar caps appear at both poles, typical for this season of transition
from southern-hemisphere winter to summer. The magenta-coloured region visible at the South Pole shows where ozone is absorbing ultraviolet light, as it
does on Earth, protecting life from harmful UV radiation.
Credit: NASA/Goddard/University of Colorado/LASP
history, and whether the planet has ever been (or is!) able to support
life.
As of 3rd October this year, MAVEN had completed one Mars year of
science observations (just under two Earth years). Among the many sig-
nificant discoveries and science results so far achieved is the most de-
tailed characterisation to date of the structure, composition, and vari-
ability of the planet’s upper atmosphere. The spacecraft has also en-
abled scientists to make the most accurate estimation yet of the rates
of past and current atmospheric loss to space, and how this is related
to the action of the solar wind and major Sun-storm events. This gas loss
would appear to have been the major factor in the transformation of
10
10
www. RocketSTEM .org