|
|
 |
Earth's Twin Seen From Saturn
[For trouble viewing the images/movies on this page, go here]
Peering over the shoulder of giant Saturn, through its rings, and across interplanetary space, NASA's Cassini spacecraft spies the bright, cloudy terrestrial planet, Venus. The vast distance from Saturn means that Venus only shows up as a white dot, just above and to the right of the image center.
Venus, along with Mercury, Earth, and Mars, is one of the rocky 'terrestrial' planets in the solar system that orbit relatively close to the sun. Though Venus has an atmosphere of carbon dioxide that reaches nearly 900 degrees Fahrenheit (500 degrees Celsius) and a surface pressure 100 times that of Earth, it is considered a twin to our planet because of their similar size, mass, rocky composition and orbit. Venus is covered in thick sulfuric acid clouds, making it very bright.
This view looks toward the unilluminated side of the rings from about 17 degrees below the ring plane. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Nov. 10, 2012.
This is a true-color picture of Saturn and Venus. A false-color mosaic including an image very similar to this one can be seen at PIA14934.
The bright arc is the limb of Saturn. A portion of the rings is seen in silhouette against the face of Saturn, which itself is faintly illuminated by sunlight scattered off the rings. The view was obtained at a distance of approximately 498,000 miles (802,000 kilometers) from Saturn and at a sun-Saturn-spacecraft, or phase, angle of 178 degrees. Image scale is 28 miles (44 kilometers) per pixel.
The Cassini Solstice Mission is a joint United States and European endeavor. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.
For more information about the Cassini Solstice Mission visit http://ciclops.org, http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov.
Credit: NASA/JPL-Caltech/Space Science Institute
Released: March 4, 2013 (PIA 14935)
Image/Caption Information |
|
PIA 14935
Avg Rating: 9.52/10
Full Size 1014x1014:
JPEG 230 KB
PNG 1.0 MB
TIFF 2.4 MB
|
Alliance Member Comments
My rating would be '12'.
This is astonishing.
The Cassini Spacecraft passed 'behind' Saturn looking towards the inner solar system through the rings when the planet Venus, some 1.44 Billion KM / 890 Million miles was spotted throuht the rings on one ocassion prior to being eclipsed & then again righ next to Saturn's limb just after. The Sun although appearing close by was eclipsed by Saturn. Both the Sun & planet Venus (Mercury, Earth & Mars too) appeared in front of the constellation of Cetus the Sea Monster, near the boundary with Aries the Ram.
I wonder if Cassini could capture Mercury, Earth (again) & Mars????
as planets go, Earth and Venus have nearly identical masses. density is nearly identical. what we know about composition tell us there are striking similarities. there are major differences in the atmospheres; Venus has such a high concentration of greenhouse gasses that while only absorbing 30% more energy from the sun, it has a surface temperature that would melt lead. but what we know and what we can infer about what is below the surfaces tell us there are more similarities than differences.
as planetary science goes, there is a lot of good reasons to refer to them as twins. keeping in mind that twins need not be identical. i would compare the differences between Earth and Venus as being like human twins with different hair styles. from a planetary science standpoint, the similarities far outweigh the differences.
"Earth's twin?" Could someone clue me in on just how Venus is Earth's "twin?" Would it be the extensive Venusian oceans? The cool, yet balmy temperatures? The clear skies and sparkling clarity of the atmosphere? The many and varied forms of life? I wouldn't even use the word "cousin" to make the comparison; "opposite" seems like it fits the bill pretty well.
Impressive image, of course; really love the golden hue of the rings.
What's Venus' apparent magnitude seen from Saturn?. I estimate it around 0 (so bright as Vega)
|
