A diagram of the Dawn spacecraft from Dawn Spacecraft Diagram No. A scaled down version of our popular series of exploration posters. From infrared images that show variations in brightness and texture, a geological map of the circular feature, thought to be a volcano, has been obtained using Cassini's visual and infrared mapping Geologic Map of Titan Volcano. The forceful storm generated unprecedented spikes in temperature and increased amounts of ethylene.
In these two sets of measurements taken by Cassini's composite infrared spectrometer, yellow repr Tracking the Saturn Storm in the Infrared. Scientists have been trying to determine what is under Tita Inside Titan.
This illustration shows the various steps that lead to the formation of the aerosols that make up the haze on Titan, Saturn's largest moon. When sunlight or highly energetic particles from Satur The Formation of Titan's Haze. The image is the first topographic map of part of Titan's north polar region. The false-color mosaic on the left was produced from overlapping stereo images from the Cassini radar instrument and Science Mission Fleet.
Cassini scientists know some of the thousands of images from the spacecraft's journey stand apart. With this feature they present the Cassini Images Hall of Fame. Cassini Images Hall of Fame. Thus, the Sun will always be at an extremely low angle at the poles. One theory of how this ice water could have been placed on Mercury is from comet residue. Mercury is the least explored "rocky" planet of our inner solar system Mercury, Venus, Earth and Mars. However it appears that Mercury holds a lot of information about how all of the terrestrial planets have evolved since the beginning times of the solar system.
Messenger should establish orbit around Mercury in March and study it for a year. Average distance from Sun: Average distance from the center of a planet to the center of the Sun. Perihelion: The point in a planet's orbit closest to the Sun. Aphelion: The point in a planet's orbit furthest from the Sun. Sidereal Rotation: The time for a body to complete one rotation on its axis relative to the fixed stars such as our Sun.
Earth's sidereal rotation is 23 hours, 57 minutes. Length of Day: The average time for the Sun to move from the Noon position in the sky at a point on the equator back to the same position. Axis tilt: Imagining that a body's orbital plane is perfectly horizontal, the axis tilt is the amount of tilt of the body's equator relative to the body's orbital plane. Earth is tilted an average of Please Contact Us.
Please try another search. Multiple locations were found. Please select one of the following:. Location Help. News Headlines. Customize Your Weather. Privacy Policy. The Planet Mercury Weather. Current Hazards. Local Radar. Mercury's low mass and proximity to the sun keep it from having anything but the thinnest of atmospheres , and this is the reason it must pass on being the hottest planet. An atmosphere helps to cloak a planet, keeping heat from leaking into space.
Without an atmosphere, Mercury loses a great deal of heat into space, rather than sharing with its night side. The hottest planet , incidentally, is Venus, the second body from the sun. Venus has a thick atmosphere that blankets the planet, keeping its temperature at an average of F C. On Earth, seasonal temperature shifts are caused by the tilt of the planet's axis. If the Southern Hemisphere is closer to the sun than its northern counterpart, it experiences spring and summer instead of autumn and winter.
But on Mercury, the planet has essentially no tilt, which means that the hemispheres experience no significant difference in temperature from one another. That allows Mercury, the closest planet to the sun, to hang onto ice at its surface. Parts of the poles never see sunlight, leading scientists to hypothesize that ice could survive on the world.
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