Incredible photo from Cassini - moons and rings

in this photo from the Cassini spacecraft in orbit around Saturn, the large moon Titan is seen backlit by the Sun.  Titan has an atmosphere which is clearly lit up to form an annulus. To the lower right, the amazing moon Enceladus, a moon which may hold liquid water under its surface.  The rings of Saturn, seen nearly edge on makes this an amazing photo. 

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Hubble Space Telescope photographs Comet ISON

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Nasa Press Release: 

In this Hubble Space Telescope composite image taken in April 2013, the sun-approaching Comet ISON floats against a seemingly infinite backdrop of numerous galaxies and a handful of foreground stars. The icy visitor, with its long gossamer tail, appears to be swimming like a tadpole through a deep pond of celestial wonders.

This photo is one of the original images featured on ISONblog, a new online source offering unique analysis of Comet ISON by Hubble Space Telescope astronomers and staff at the Space Telescope Science Institute in Baltimore, Md. For more on ISONblog, visit: Hubble Comet ISON 

 

NASA's Spitzer Observes Gas Emission From Comet ISON

(NASA/JPL Press Release)

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Astronomers using NASA's Spitzer Space Telescope have observed what most likely are strong carbon dioxide emissions from Comet ISON ahead of its anticipated pass through the inner solar system later this year. 

Images captured June 13 with Spitzer's Infrared Array Camera indicate carbon dioxide is slowly and steadily "fizzing" away from the so-called "soda-pop comet," along with dust, in a tail about 186,400 miles (300,000 kilometers) long. 

"We estimate ISON is emitting about 2.2 million pounds (1 million kilograms) of what is most likely carbon dioxide gas and about 120 million pounds (54.4 million kilograms) of dust every day," said Carey Lisse, leader of NASA's Comet ISON Observation Campaign and a senior research scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "Previous observations made by NASA's Hubble Space Telescope and the Swift Gamma-Ray Burst Mission and Deep Impact spacecraft gave us only upper limits for any gas emission from ISON. Thanks to Spitzer, we now know for sure the comet's distant activity has been powered by gas." 

Comet ISON was about 312 million miles (502 million kilometers) from the sun, 3.35 times farther than Earth, when the observations were made. 

"These fabulous observations of ISON are unique and set the stage for more observations and discoveries to follow as part of a comprehensive NASA campaign to observe the comet," said James L. Green, NASA's director of planetary science in Washington. "ISON is very exciting. We believe that data collected from this comet can help explain how and when the solar system first formed." 

Comet ISON (officially known as C/2012 S1) is less than 3 miles (4.8 kilometers) in diameter, about the size of a small mountain, and weighs between 7 billion and 7 trillion pounds (3.2 billion and 3.2 trillion kilograms). Because the comet is still very far away, its true size and density have not been determined accurately. Like all comets, ISON is a dirty snowball made up of dust and frozen gases such as water, ammonia, methane and carbon dioxide. These are some of the fundamental building blocks, which scientists believe led to the formation of the planets 4.5 billion years ago. 

Comet ISON is believed to be inbound on its first passage from the distant Oort Cloud, a roughly spherical collection of comets and comet-like structures that exists in a space between one-tenth light-year and 1 light-year from the sun. The comet will pass within 724,000 miles (1.16 million kilometers) of the sun on Nov. 28. 

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Here is a web site devoted to Comet ISON News. 

  

 

 

Cassini picture of Earth released

(From NASA/Cassini Press Release) 

Our home planet and its moon appear as a mere dots - the Earth a pale blue and the Moon a stark white - in new color images taken from nearly 900 million miles away by the cameras on NASA's Cassini spacecraft. The images were taken on July 19, 2013 during an event that was observed and celebrated worldwide.

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The July 19 Earth-imaging event marked the first time Earthlings had advance notice that their portrait was being taken from interplanetary distances. It was the also the first time Cassini's highest resolution camera captured the Earth and its moon as two distinct objects. NASA invited the public to acknowledge the occasion by either finding Saturn in their part of the sky and waving, or simply smiling and celebrating. At least 20,000 people around the world participated. 

"We may not be able to see individual continents or people in this portrait of Earth, but this pale blue dot is a succinct summary of who we were on July 19," said Linda Spilker, Cassini project scientist, based at NASA's Jet Propulsion Laboratory. "Cassini's picture reminds us how tiny our home planet is in the vastness of space, but also testifies to the ingenuity of the citizens of this tiny planet to be able to send a robotic spacecraft so far away from home to take a picture of Earth and study a distant world like Saturn."