OrbitalHub

NASA dixit:

“March 3, 2010. The Cassini spacecraft snapped this image during the spacecraft’s closest flyby of Saturn’s moon Helene (33 kilometers, or 21 miles across). The small moon leads the much larger Dione by 60 degrees in the moons’ shared orbit. Helene is a “Trojan” moon of Dione, named for the Trojan asteroids that orbit 60 degrees ahead of and behind Jupiter as the giant planet circles the Sun.

Lit terrain seen here is on the anti-Saturn side of Helene. The south pole of the moon is in the lower right of the image. The image was taken in visible light with the Cassini spacecraft wide-angle camera. The view was obtained at a distance of approximately 1,900 kilometers (1,200 miles) from Helene and at a Sun-Helene-spacecraft, or phase, angle of 90 degrees. Scale in the original image was 235 meters (771 feet) per pixel. The image has been magnified by a factor of two and contrast-enhanced to aid visibility.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. And those six months are the thrilling final chapter in a historic 20-year journey.”

Image credit: NASA

NASA dixit:

“March 3, 2010. Although traveling at great speed, the Cassini spacecraft managed to capture this close view of Saturn’s small moon Helene during a flyby. Saturn’s atmosphere makes up the background of this composition. This view looks toward the anti-Saturn side of Helene (33 kilometers, or 21 miles across). North on Helene is up and rotated 44 degrees to the right.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera. The view was obtained at a distance of approximately 19,000 kilometers (12,000 miles) from Helene and at a sun-Helene-spacecraft, or phase, angle of 25 degrees. Image scale is 113 meters (371 feet) per pixel.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. And those six months are the thrilling final chapter in a historic 20-year journey.”

Image credit: NASA

NASA dixit:

“November 21, 2009. Dramatic plumes, both large and small, spray water ice and vapor from many locations along the famed “tiger stripes” near the south pole of Saturn’s moon Enceladus. The tiger stripes are four prominent, approximately 84-mile- (135-kilometer-) long fractures that cross the moon’s south polar terrain. This two-image mosaic is one of the highest resolution views acquired by Cassini during its imaging survey of the geyser basin capping the southern hemisphere of Saturn’s moon Enceladus. It clearly shows the curvilinear arrangement of geysers, erupting from the fractures. From left to right, the fractures are Alexandria, Cairo, Baghdad, and Damascus.

As a result of this survey, 101 geysers were discovered: 100 have been located on one of the tiger stripes, and the three-dimensional configurations of 98 of these geysers have also been determined. The source location of the remaining geyser could not be definitively established. These results, together with those of other Cassini instruments, now strongly suggest that the geysers have their origins in the sea known to exist beneath the ice underlying the south polar terrain.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. And those six months are the thrilling final chapter in a historic 20-year journey.”

Image credit: NASA

NASA dixit:

“October 19, 2009. The Cassini spacecraft captures a couple of small moons in this image taken while the spacecraft was nearly in the plane of Saturn’s rings. Near the top of this image, a crescent Mimas (396 kilometers, or 246 miles across) is closer to Cassini than the rings are. Pan (28 kilometers, or 17 miles across) is visible as a tiny dot in the Encke Gap of the A ring near the middle of the bottom of the image. This view looks toward the northern, sunlit side of the rings from just above the ringplane.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera. The view was obtained at a distance of approximately 2.1 million kilometers (1.3 million miles) from Pan. Image scale is 13 kilometers (8 miles) per pixel.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. And those six months are the thrilling final chapter in a historic 20-year journey.”

Image credit: NASA

NASA dixit:

“October 18, 2009. Orbiting near the plane of Saturn’s rings, the Cassini spacecraft looks across the span of the rings to spy the small moon Epimetheus. The brightest spoke is visible on the left of the image, but others can be seen near the middle of the image and elsewhere on the B ring.

This view looks toward the northern, sunlit side of the rings from about 1 degree above the ringplane. Cassini is closer to the rings than to Epimetheus (113 kilometers, or 70 miles across). Two background stars are visible. The image was taken in visible light with the Cassini spacecraft narrow-angle camera. The view was acquired at a distance of approximately 2.2 million kilometers (1.4 million miles) from Epimetheus. Image scale is 13 kilometers (8 miles) per pixel.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. And those six months are the thrilling final chapter in a historic 20-year journey.”

Image credit: NASA

NASA dixit:

“July 26, 2009. The Cassini spacecraft captured this image of a small object in the outer portion of Saturn’s B ring casting a shadow on the rings as Saturn approaches its August 2009 equinox. This new moonlet, situated about 300 miles (480 kilometers), inward from the outer edge of the B ring, was found by detection of its shadow which stretches 25 miles, or 41 kilometers, across the rings. The shadow length implies the moonlet is protruding about 660 feet, or 200 meters, above the ring plane. If the moonlet is orbiting in the same plane as the ring material surrounding it, which is likely, it must be about 1,300 feet, or 400 meters, across.

This object is not attended by a propeller feature, unlike the band of moonlets discovered in Saturn’s A ring earlier by Cassini. The A ring moonlets, which have not been directly imaged, were found because of the propeller-like narrow gaps on either side of them that they create as they orbit within the rings. The lack of a propeller feature surrounding the new moonlet is likely because the B ring is dense, and the ring material in a dense ring would be expected to fill in any gaps around the moonlet more quickly than in a less dense region like the mid-A ring. Also, it may simply be harder in the first place for a moonlet to create propeller-like gaps in a dense ring.

This image and others like it are only possible around the time of Saturn’s equinox which occurs every half-Saturn-year (equivalent to about 15 Earth years). The illumination geometry that accompanies equinox lowers the sun’s angle to the ring plane and causes out-of-plane structures to cast long shadows across the rings. This view looks toward the sunlit side of the rings from about 42 degrees below the ring plane. Background stars are visible on the right of the image. They appear elongated by the camera’s exposure time.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera. The view was obtained at a distance of approximately 296,000 kilometers (184,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 120 degrees. Image scale is 1 kilometer (4,680 feet) per pixel.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. And those six months are the thrilling final chapter in a historic 20-year journey.”

Image credit: NASA