space-mission

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Approach and Landing Test

(A preview of a new series on distancetomars, 135 in 135, following the entire Shuttle Program from start to finish.  135 in 135 will be posted daily, for all your Shuttle needs)

Orbiter: OV-101, Enterprise. Enterprise was built in 1976 by Rockwell International, serving as a testbed for atmospheric flight.  Enterprise was built without engines and without a heatshield, and thus never flew in space.

Mission: ALT-14, third free flight of the Space Shuttle Enterprise. The mission was to test flight characteristics of the orbiter, simulating a standard landing profile while returning from orbit.  The Orbiter was carried into the air by a modified Boeing 747 and then released to glide back down to a lake bed runway at Dryden for landing. Enterprise wore a tail cone during this mission, to reduce drag while on top of the 747 carrier.

Launch Date/Location: September 23, 1977. Dryden Flight Research Center, Edwards Air Force Base, California

Crew: Fred Haise (Apollo 13), Gordon Fullerton (first flight)

Payload: No payload, atmospheric test flight.

Landing Date/Location: September 23, 1977 (5m 34s flight time).  Dryden Flight Research Center, Edwards Air Force Base, California

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NASA plans a robotic mission to search for life on Europa | io9

It looks like it’s finally going to happen, an actual mission to Jupiter’s icy moon Europa — one of the the solar system’s best candidates for hosting alien life.

Yesterday, NASA announced an injection of $17.5 billion from the federal government (down by $1.2 billion from its 2010 peak). Of this, $15 million will be allocated for “pre-formulation” work on a mission to Europa, with plans to make detailed observations from orbit and possibly sample its interior oceans with a robotic probe. Mission details are sparse, but if all goes well, it could be launched by 2025 and arriving in the early 2030s.

This is incredibly exciting. Recent evidence points to a reasonable chance of habitability. Its massive subsurface ocean contains almost twice as much water as found on Earth. The water is kept in liquid state owing to the gravitational forces exerted by Jupiter and the moon’s turbulent global ocean currents. The good news is that a probe may not have to dig very deep to conduct its search for life; the moon’s massive plumes are ejecting water directly onto the surface.

[Read more]

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NASA Probe Gets Close Views of Large Saturn Hurricane

NASA’s Cassini spacecraft has provided scientists the first close-up, visible-light views of a behemoth hurricane swirling around Saturn’s north pole.

In high-resolution pictures and video, scientists see the hurricane’s eye is about 1,250 miles (2,000 kilometers) wide, 20 times larger than the average hurricane eye on Earth. Thin, bright clouds at the outer edge of the hurricane are traveling 330 mph(150 meters per second). The hurricane swirls inside a large, mysterious, six-sided weather pattern known as the hexagon.

"We did a double take when we saw this vortex because it looks so much like a hurricane on Earth," said Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena. "But there it is at Saturn, on a much larger scale, and it is somehow getting by on the small amounts of water vapor in Saturn’s hydrogen atmosphere."

Scientists will be studying the hurricane to gain insight into hurricanes on Earth, which feed off warm ocean water. Although there is no body of water close to these clouds high in Saturn’s atmosphere, learning how these Saturnian storms use water vapor could tell scientists more about how terrestrial hurricanes are generated and sustained.

Both a terrestrial hurricane and Saturn’s north polar vortex have a central eye with no clouds or very low clouds. Other similar features include high clouds forming an eye wall, other high clouds spiraling around the eye, and a counter-clockwise spin in the northern hemisphere.

A major difference between the hurricanes is that the one on Saturn is much bigger than its counterparts on Earth and spins surprisingly fast. At Saturn, the wind in the eye wall blows more than four times faster than hurricane-force winds on Earth. Unlike terrestrial hurricanes, which tend to move, the Saturnian hurricane is locked onto the planet’s north pole. On Earth, hurricanes tend to drift northward because of the forces acting on the fast swirls of wind as the planet rotates. The one on Saturn does not drift and is already as far north as it can be.

"The polar hurricane has nowhere else to go, and that’s likely why it’s stuck at the pole," said Kunio Sayanagi, a Cassini imaging team associate at Hampton University in Hampton, Va.

Scientists believe the massive storm has been churning for years. When Cassini arrived in the Saturn system in 2004, Saturn’s north pole was dark because the planet was in the middle of its north polar winter. During that time, the Cassini spacecraft’s composite infrared spectrometer and visual and infrared mapping spectrometer detected a great vortex, but a visible-light view had to wait for the passing of the equinox in August 2009. Only then did sunlight begin flooding Saturn’s northern hemisphere. The view required a change in the angle of Cassini’s orbits around Saturn so the spacecraft could see the poles.

"Such a stunning and mesmerizing view of the hurricane-like storm at the north pole is only possible because Cassini is on a sportier course, with orbits tilted to loop the spacecraft above and below Saturn’s equatorial plane," said Scott Edgington, Cassini deputy project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. "You cannot see the polar regions very well from an equatorial orbit. Observing the planet from different vantage points reveals more about the cloud layers that cover the entirety of the planet."

Cassini changes its orbital inclination for such an observing campaign only once every few years. Because the spacecraft uses flybys of Saturn’s moon Titan to change the angle of its orbit, the inclined trajectories require attentive oversight from navigators. The path requires careful planning years in advance and sticking very precisely to the planned itinerary to ensure enough propellant is available for the spacecraft to reach future planned orbits and encounters.

Image credit: NASA/JPL-Caltech/SSI

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The Moon’s Fragile Atmosphere

The moon orbits the earth with a period of four weeks ( a month) and during the orbit it always has the same side facing the earth. So this means that on the moon there is day and night, but they are both two weeks long instead of 24 hours.

The Moon’s daylight is brighter and harsher than the Earth’s. There is no atmosphere to scatter the light, no clouds to shade it, and no ozone layer to block the sunburning ultraviolet light. However, there is a very, very thin layer of gases on the lunar surface that can almost be called an atmosphere. Technically, it’s considered a surface boundary exosphere.

One of the critical differences between the atmospheres of Earth and the moon is how atmospheric molecules move. Here in the dense atmosphere at the surface of Earth, the molecules’ motion is dominated by collisions between the molecules.The exosphere is so thin that molecules in the lunar exosphere almost never collide with each other. During the lunar night, the Moon’s exosphere mostly falls to the ground. When sunlight returns, the solar wind kicks up new particles to replenish the exosphere.

The intense ultraviolet sunlight kicks electrons off particles in the lunar soil, giving those particles an electric charge that can cause them to levitate. Ambient electric fields lift these charged dust particles as high as kilometers above the surface, forming an important part of the exosphere. Moon dust wrecked havoc with the Apollo spacesuits, which were nearly threadbare by the time they returned to Earth. Levitating dust can get into equipment, spacesuits, and computers, causing damage and shortening the hardware’s useful life. Knowing how much dust is floating around in the exosphere and how it behaves will help engineers design next-generation lunar hardware.

Credit: Science@NASA

Apollo 16: Exploring Plum Crater

Apollo 16 spent three days on Earth’s Moon in April 1972. The fifth lunar landing mission out of six, Apollo 16 was famous for deploying and using an ultraviolet telescope as the first lunar observatory, and for collecting rocks and data on the mysterious lunar highlands. In the above picture, astronaut John W. Young photographs Charles M. Duke, Jr. collecting rock samples at the Descartes landing site. The Lunar Roving Vehicle allowed the astronauts to travel great distances to investigate surface features and collect rocks. High above, Thomas K. Mattingly orbits in the Command Module.

Credit: John W. Young, Apollo 16 Crew, NASA

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Today the Mars Orbiter Mission, better known as Mangalyaan, was inserted into a Mars orbit. The successful insertion makes India the fourth nation to reach Mars after the US, the Soviet Union and Europe. In the pictures are ISRO scientist and engineers celebrating its success.

Congratulations to ISRO and its scientist and engineers!

Images sources: x, y