Astronomy Picture of the Day |
APOD: 1996 September 23 - Venus: Earth's Cloudy Twin
Explanation:
If Venus weren't so cloudy it would be more
similar to Earth. This picture by the Galileo spacecraft
shows just how cloudy Venus
is. Venus
is very similar to Earth in size
and mass - and so is sometimes referred to as Earth's sister planet
- but Venus
has a quite different climate. Venus'
thick clouds and closeness to the Sun
(only Mercury is closer) make it
the hottest planet - much hotter than the Earth. Humans could
not survive there, and no life of any sort has ever been found.
When Venus is visible
it is usually the brightest object in the sky after the Sun and
the Moon. More than 20 spacecraft
have visited Venus
including Venera 9,
which landed on the surface, and Magellan,
which used radar to peer through the clouds and make a map of
the surface. This visible light picture of Venus
was taken by the Galileo spacecraft now
in orbit around Jupiter. Many things about Venus remain unknown,
including the cause of mysterious bursts of radio waves.
APOD: 1999 November 28 - Beneath Venus' Clouds
Explanation:
If the thick clouds covering Venus were removed,
how would the surface appear?
Using an imaging radar technique, the Magellan spacecraft was able to
lift the veil from the Face of Venus and produce this spectacular high resolution image of
the planet's surface.
Red, in this false-color map, represents
mountains, while blue represents valleys.
This 3-kilometer resolution
map is a composite of Magellan images compiled between 1990 and 1994.
Gaps were filled in by the Earth-based
Arecibo Radio Telescope.
The large yellow/red area in the north is
Ishtar Terra featuring Maxwell Montes,
the largest mountain on Venus.
The large highland regions are analogous to continents on Earth.
Scientists are particularly interested in
exploring the geology of
Venus because of its similarity to Earth.
APOD: 1999 January 24 - A Venus Landing
Explanation:
This image is part of the first color panoramic view from
Venus.
It was transmitted by a TV camera on the
Soviet Venera 13 lander
which parachuted to thesurface
on March 1, 1982.
Venus' clouds
are composed of sulfuric acid droplets
while its surface temperature is about 900 degrees Fahrenheit
(482 degrees C) at an atmospheric
pressure of 92 times that of sea-level on Earth.
Despite these harsh conditions, the
Venera 13 lander survived
long enough to send back a series of images
and perform an analysis of the
Venusian soil.
Part of the lander itself
is visible in the lower right portion of the image.
An earlier Soviet Venus lander,Venera 7 (1970), was the first spacecraft to return data
from the surface of another planet.
Authors & editors:
Robert
Nemiroff
(MTU)
& Jerry Bonnell (USRA)
NASA Technical Rep.:
Jay Norris.
Specific rights apply.
A service of:
LHEA at
NASA/
GSFC
&
Michigan Tech. U.