Diving Through Saturn Moon�s Icy Plume

Scientists are about to get their best look ever at the ocean that sloshes beneath the surface of Saturn’s icy moon Enceladus.
On Wednesday (Oct 28), NASA’s Cassini spacecraft was to zoom just 50 kilometres above Enceladus, flying through and sampling the plume of material that erupts from the satellite’s south polar region.

This plume is thought to originate from Enceladus’ underground liquid-water ocean, so Cassini’s onboard sample analysis should shed light on the moon’s potential to host life, mission team members said.

“On Wednesday, we will plunge deeper into the magnificent plume coming from the south pole than we ever have before, and we will collect the best samples ever from an ocean beyond Earth,” Curt Niebur, Cassini program scientist at NASA Headquarters in Washington, DC, said during a news conference on Monday.
Enceladus has an extensive water ocean under its icy crust, feeding water jets that emerge from near the south pole.  
Cassini is not equipped to search for signs of life, but the probe’s measurements should help researchers assess the habitability of Enceladus’ global ocean, Niebur added.

There are three main science objectives for the flyby, said Cassini project scientist Linda Spilker, who’s based at NASA’s Jet Propulsion Laboratory in Pasadena, California: The mission team aims to confirm the presence of molecular hydrogen in the plume, which would provide evidence forhydrothermal activity (a potential energy source for life) in the ocean. The team also hopes to characterize the plume’s chemistry (perhaps finding previously undetected organic compounds) and determine the nature of the plume sources (discrete jets versus broader, curtainlike eruptions).
Spilker said the flyby is to occur at about 1700 GMT on Wednesday. Cassini will check in with mission control about 3 hours later, but the first encounter images likely won’t be released until late Thursday or early Friday.

Scientists will probably get their first quick look at Cassini’s spectrometer data on the sampled plume particles within a week after the flyby, but more in-depth analysis may take several weeks, she added.
Wednesday’s close encounter will mark the 21st flyby of Enceladus for Cassini, which has been orbiting Saturn since 2004 and discovered the moon’s icy geysers in 2005. Cassini has flown through the plume before, but its previous closest approach to the south polar region was 80 km.

After Wednesday, Cassini will have one more flyby of Enceladus remaining before the end of its mission, in September 2017. On Dec 19, the spacecraft will cruise within 4,999 km of the icy satellite, making observations that should allow mission scientists to gauge the heat flowing from Enceladus’ interior.

The $3.2 billion Cassini mission, a joint effort involving NASA, the European Space Agency and the Italian Space Agency, launched in 1997.

Source: www.space.com

3 Planets Align in Rare Sky Show

 

The eastern sky last week played host to a cosmic show that hasn’t been seen in two years and won’t be seen again for another five years.
Stargazers caught Venus, Jupiter and Mars in what is called a planetary trio -- any grouping of three planets inside a circle with a 5 degree diametre, or the typical field of view on a pair of binoculars.
According to EarthSky.org, the closest grouping of the trio was around dawn on Monday. But the three planets could be spotted every morning through Thursday towards the east, about an hour before sunrise, when even the relatively dim planet Mars was most visible to the naked eye.
Courtesy of
While these planets looked close to each other from Earth, in reality they are separated by hundreds of millions of miles. NASA says that these kinds of celestial events “have no real astronomical value,” but they are still pretty cool to witness.
In addition to the planetary trio, Monday also marked Jupiter’s greatest western elongation -- in other words, Jupiter was at its farthest from the sunrise on that day. Jupiter was officially in conjunction with Venus, meaning that the two planets had the same right ascension, the celestial equivalent of longitude.
While the conjunction of planets isn’t extremely rare, EarthSky says that the next planetary trio won’t happen until January 2021.
Source: abcnews

 

 

Diving Through Saturn Moon�s Icy Plume

Scientists are about to get their best look ever at the ocean that sloshes beneath the surface of Saturns icy moon Enceladus. On Wednesday (Oct 28), NASAs Cassini spacecraft was to zoom just 50 kilometres above Enceladus, flying through and sampling the plume of material that erupts from the satellites south polar region. This plume is thought to originate from Enceladus underground liquid-water ocean, so Cassinis onboard sample analysis should shed light on the moons potential to host life, mission team members said. On Wednesday, we will plunge deeper into the magnificent plume coming from the south pole than we ever have before, and we will collect the best samples ever from an ocean beyond Earth, Curt Niebur, Cassini program scientist at NASA Headquarters in Washington, DC, said during a news conference on Monday. Enceladus has an extensive water ocean under its icy crust, feeding water jets that emerge from near the south pole. Cassini is not equipped to search for signs of life, but the probes measurements should help researchers assess the habitability of Enceladus global ocean, Niebur added. There are three main science objectives for the flyby, said Cassini project scientist Linda Spilker, whos based at NASAs Jet Propulsion Laboratory in Pasadena, California: The mission team aims to confirm the presence of molecular hydrogen in the plume, which would provide evidence forhydrothermal activity (a potential energy source for life) in the ocean. The team also hopes to characterize the plumes chemistry (perhaps finding previously undetected organic compounds) and determine the nature of the plume sources (discrete jets versus broader, curtainlike eruptions). Spilker said the flyby is to occur at about 1700 GMT on Wednesday. Cassini will check in with mission control about 3 hours later, but the first encounter images likely wont be released until late Thursday or early Friday. Scientists will probably get their first quick look at Cassinis spectrometer data on the sampled plume particles within a week after the flyby, but more in-depth analysis may take several weeks, she added. Wednesdays close encounter will mark the 21st flyby of Enceladus for Cassini, which has been orbiting Saturn since 2004 and discovered the moons icy geysers in 2005. Cassini has flown through the plume before, but its previous closest approach to the south polar region was 80 km. After Wednesday, Cassini will have one more flyby of Enceladus remaining before the end of its mission, in September 2017. On Dec 19, the spacecraft will cruise within 4,999 km of the icy satellite, making observations that should allow mission scientists to gauge the heat flowing from Enceladus interior. The $3.2 billion Cassini mission, a joint effort involving NASA, the European Space Agency and the Italian Space Agency, launched in 1997. Source: www.space.com 3 Planets Align in Rare Sky Show The eastern sky last week played host to a cosmic show that hasnt been seen in two years and wont be seen again for another five years. Stargazers caught Venus, Jupiter and Mars in what is called a planetary trio -- any grouping of three planets inside a circle with a 5 degree diametre, or the typical field of view on a pair of binoculars. According to EarthSky.org, the closest grouping of the trio was around dawn on Monday. But the three planets could be spotted every morning through Thursday towards the east, about an hour before sunrise, when even the relatively dim planet Mars was most visible to the naked eye. Courtesy of While these planets looked close to each other from Earth, in reality they are separated by hundreds of millions of miles. NASA says that these kinds of celestial events have no real astronomical value, but they are still pretty cool to witness. In addition to the planetary trio, Monday also marked Jupiters greatest western elongation -- in other words, Jupiter was at its farthest from the sunrise on that day. Jupiter was officially in conjunction with Venus, meaning that the two planets had the same right ascension, the celestial equivalent of longitude. While the conjunction of planets isnt extremely rare, EarthSky says that the next planetary trio wont happen until January 2021. Source: abcnews