Here’s what NASA has to say about Cassini’s Enceladus flyby
NASA revealed earlier that its Cassini spacecraft will be flying close to Enceladus – specifically through one of its icy plumes – and this got the media into a ‘life on Enceladus’ frenzy.
In a bid to reveal to clarify a few things and to detail what exactly its missions scientists are hoping to achieve through the close flyby, NASA has put out seven key facts about the event. According to NASA, scientists are not looking for alien life, but intend to garner insights into the level of hydrothermal activity within Enceladus.
During the close flyby scheduled for October 28 at an altitude of just 30 miles (49 kilometers) above the moon’s south polar region, the spacecraft will be flying through the moon’s plume of icy spray and scientists are hoping to detect hydrogen as well as heavier molecules. Further, they also intend to gain insights into how hot-water chemistry might impact the ocean’s potential habitability for simple forms of life.
Some of the information released prior to the close flyby is listed below:
- Enceladus is an icy moon of Saturn. Early in its mission, Cassini discovered Enceladus has remarkable geologic activity, including a towering plume of ice, water vapor and organic molecules spraying from its south polar region. Cassini later determined the moon has a global ocean and likely hydrothermal activity, meaning it could have the ingredients needed to support simple life.
- The flyby will be Cassini’s deepest-ever dive through the Enceladus plume, which is thought to come from the ocean below. The spacecraft has flown closer to the surface of Enceladus before, but never this low directly through the active plume.
- The flyby is not intended to detect life, but it will provide powerful new insights about how habitable the ocean environment is within Enceladus.
- Cassini scientists are hopeful the flyby will provide insights about how much hydrothermal activity — that is, chemistry involving rock and hot water — is occurring within Enceladus. This activity could have important implications for the potential habitability of the ocean for simple forms of life. The critical measurement for these questions is the detection of molecular hydrogen by the spacecraft.
- Scientists also expect to better understand the chemistry of the plume as a result of the flyby. The low altitude of the encounter is, in part, intended to afford Cassini greater sensitivity to heavier, more massive molecules, including organics, than the spacecraft has observed during previous, higher-altitude passes through the plume.
- The flyby will help solve the mystery of whether the plume is composed of column-like, individual jets, or sinuous, icy curtain eruptions — or a combination of both. The answer would make clearer how material is getting to the surface from the ocean below.
- Researchers are not sure how much icy material the plumes are actually spraying into space. The amount of activity has major implications for how long Enceladus might have been active.