- 2940 - ENCELADUS - visit Saturn’s moon? One of the biggest findings was that the icy Moon Enceladus has a subsurface ocean that vents water into space. Fissures slashed across the south pole have temperatures warm enough to suggest the ocean is being heated by the moon’s core. On Earth, similar spots called hydrothermal vents are hotspots for life.
------------------ 2940 - ENCELADUS - visit Saturn’s moon?
- ‘Orbilander“ is the name for a Mission to Search for Life on Saturn’s moon Enceladus.
NASA’s Cassini spacecraft left a legacy of discoveries behind when its 13-year-mission to Saturn ended in 2017.
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- Mission Orbilander is named for its ability to function as both an orbiter and a lander. Orbilander’s mission is geared towards a single question: is there life on Enceladus? We know there is a subsurface ocean, and we have every reason to suspect it is habitable.
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- A flagship mission with a price tag of $2.5 billion. Orbilander’s mission would start by orbiting Enceladus for approximately 200 days.
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- Despite their brilliant appearance in Cassini images, Enceladus’ plumes are not very dense. Orbilander will be flying through something more like a cloud than a garden sprinkler. Particles from the plumes will funnel into science instruments at high speeds as the spacecraft zips along, requiring the spacecraft to gently decelerate so they aren’t pulverized.
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- A lot of the time in orbit will be spent looking for the right place to land. Despite Cassini’s extensive surveillance of Saturn and its moons, there isn’t enough high-resolution topography data available for Enceladus’ south pole.
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- Once a landing location is found, Orbilander would turn on its side and convert to a lander. It would descend using terrain-relative navigation similar to what OSIRIS-REx will use to capture a sample from asteroid Bennu, and what the Dragonfly mission to Saturn’s moon Titan will use to fly around the surface.
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- Two nuclear power sources will keep Orbilander running on the surface for up to a year and a half.
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- Orbilander would rely on a complex suite of instruments to determine whether Enceladus’ water has a blend of chemicals conducive for life as we know it, and search for amino acids, lipids, and cells.
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- The instruments include mass spectrometers to weigh and analyze molecules, a seismometer, a microscope, and a DNA sequencer. For remote sensing, the spacecraft would have cameras, radar sounders, and a laser altimeter.
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- Six different instruments will provide indications of several different biosignatures. That way, the end result is more compelling than a single detection.
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- Unlike most other moons with subsurface oceans, Enceladus’ geysers offer a unique opportunity to sample the water without having to drill through the surface. Not only will Orbilander access the plumes by flying through them in orbit, it will also capture plume material falling back to the surface after the spacecraft lands.
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- To the human eye, Enceladus appears all-white, but infrared and ultraviolet views have highlight fractures where the moon's subsurface ocean vents into space. The vents are commonly called "tiger stripes.
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- Orbilander wouldn’t launch until 2038 and arrive at Enceladus until at least 2050. That year Encleadus’ south pole will be in sunlight. A lot of what we know about Enceladus came from the previous mission “Cassini”
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- Composite images made from NASA's Cassini spacecraft are the most detailed global infrared views ever produced of Saturn's moon Enceladus. And data used to build those images provides strong evidence that the northern hemisphere of the moon has been resurfaced with ice from its interior.
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- Cassini's Visible and Infrared Mapping Spectrometer (VIMS) collected light reflected off Saturn, its rings and its ten major icy moons, light that is visible to humans as well as infrared light. VIMS then separated the light into its various wavelengths, information that tells scientists more about the makeup of the material reflecting it.
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- Cassini scientists discovered in 2005 that Enceladus, which looks like a highly reflective, bright white snowball to the naked eye, shoots out enormous plumes of ice grains and vapor from an ocean that lies under the icy crust.
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- The spectral map showed that infrared signals clearly correlate with that geologic activity, which is easily seen at the south pole. That's where the so-called "tiger stripe" gashes blast ice and vapor from the interior ocean.
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- Some of the same infrared features also appear in the northern hemisphere. That tells scientists not only that the northern area is covered with fresh ice but that the same kind of geologic activity, a resurfacing of the landscape, has occurred in both hemispheres. The resurfacing in the north may be due either to icy jets or to a more gradual movement of ice through fractures in the crust, from the subsurface ocean to the surface.
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- Cassini was an orbiter that observed Saturn for more than 13 years before exhausting its fuel supply. The mission plunged it into the planet's atmosphere in September 2017, in part to protect Enceladus, which has the potential of holding conditions suitable for life, with its ocean likely heated and churned by hydrothermal vents like those on Earth's ocean floors.
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----------------------- Other reviews available about Saturn’s moons:
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- 2864 - ENCELADUS - Saturn’s moon. Enceladus, named after one of the Giants in Greek mythology, has an icy surface that reflects 81 percent of the light falling on it. Saturn’s sixth-largest moon, Enceladus has a diameter of only 310 miles, and a mass less than 1/50,000 that of Earth.
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- 1786 - Enceladus - Saturn’s moon. This review describes what we have learned from recent space probes. It’s a whole new world to spur the imagination. Enceladus has groves in its surface that are measurably warmer than the surrounding terrain. These groves are venting huge clouds of water vapor and ice crystals. Enceladus is barely 500 kilometers across ( 311 miles ). It would fit insi]de the borders of Colorado.
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- 1714 - Saturn’s moon - Enceladus New discoveries suggest an underwater ocean that contains ammonia anti-freeze and exits plums or geysers through the thick icy crust on the surface. Check the data and see if you agree?
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- 1362 - Enceladus - Saturn’s moon Enceladus was first discovered in 1789. It is only 310 miles in diameter, 1/7th the diameter of the Moon. The surface of Enceladus is water ice. In 1980 Voyager 2 spacecraft photographed Enceladus’ craters, narrow valleys, groves and ridges. It found sharp edged canyons 120 miles long, 5 miles wide, and ½ mile deep. All later to be discovered as water ice.
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- 1166 - Saturn has 62 moons. The plums on Enceladus are called cryo-volcanoes. The temperature of the water is -136 F but still liquid because it contains ammonia which is a natural anti-freeze.
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- 1362 - The escape velocity is only 500 miles per hour. The temperature is -337 F
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- 957 - Enceladus is 311 miles in diameter and would fit inside the state of Colorado. It is the second closest moon orbiting Saturn outside the rings by 148,000 miles
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December 17, 2020 ENCELADUS - visit Saturn’s moon? 2932
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