NASA Missions to Planets and Others

SATURN

The launch date for the "Cassini Orbiter" was October 15, 1997. It arrived near Saturn on June 30, 2004 after during "flybys" of both Venus and Jupiter. It is a "flyby" mission because Saturn is a "gas" giant with no "hard" surface on which to land. It had a Primary mission date of 4 years which was completed in June 2008. However, it was performing so well and returning just wonderful pictures of Saturn and it's moons that it received a mission extension which goes through September 2017.



Cassini during it long presence near Saturn has made intensive studies of the atmosphere of Saturn, it's rings and their composition having discovered many previously unknown rings with various scientific onboard instruments.

In addition to Saturn itself, it also makes studies of Saturn's moons including Titan, Enceladus, Dione, Rhea and Mimas. Saturn has a total of at least 62 moons, many of which are very small icy "moonlets". There may be many more unknown.

One of the most outstanding features of the Cassini mission as the launch of the "Huygens Probe" to Saturn's moon "Titan". Huygens probe Titan release date: December 24, 2004. The arrival and descent to Titan was on January 14, 2005. Huygens' entry speed into Titan's atmosphere: about 20,000 kph (12,400 mph).

MARS

The launch date for "Mars Exploration Rover - Spirit" was June 10, 2003. It landed on Mars January 4, 2004.

The "Spirit" rover landed on the opposite side of Mars from a sister rover named "Opportunity". (See more regarding "Opportunity" rover below. While the length of the mission was originally programmed for about 90 days, it lasted a much longer time as the final shutdown occurred on May 25, 2011, after having become "stuck" in the Martian sand for some months. Even while "stuck", it continued to explore and take pictures of it's surrounding region.


The launch date for "Mars Exploration Rover - Opportunity" was July 07, 2003. It landed on Mars January 25, 2004. It's original mission was also programmed for about 90 days but again, along with rover "Spirit", it has lasted a much longer time and is still active (August 2011). NASA was very lucky with the landing spot of the rover "Opportunity" as it landed right in the middle of a Martian crater where it began immediate exploration. During it's time on time, it has visited many other craters and Martian landmarks in the area. Rover "Opportuniity" also became "stuck" in the sand for a time but was able to finally resume exploratins in the area.

VENUS

There have been several "flybys" of the planet Venus. The most recent was NASA's "Magellan Mission to Venus". The launch date for "Magelian" was JMay 4, 1989 and arrived at Venus on August 10, 1990 was inserted into a polar orbit around Venus. Magellian's primary mission was to "map" Venus via radar which it did. The mapping mission was divided up into "cycles", each cycle lasted 243 days (the time necessary for Venus to rotate once under the Magellan orbit - that is, the time necessary for Magellan to "see" the entire surface once.) Magellian experienced mechanical problems and the contact with the orbiter was last and the mission was concluded on Oct 13 1994. Not only did we receive detailed "radar maps" of Venus but the spacecraf was also able to do extension study of volcanic activity on Venus.


{Dwarf Planets, Asteroids and Comets}

The following descriptions will listed as "missions" since many of these visit more than one object in space.

"DAWN" Mission:

Launched in September, 2007, "Dawn" spacecraft has been traveling to observe up close the asteroid Vest and the dwarf Planet Ceres, two objects in space associated with the early formation of our solar system.

Dawn arrived near Vesta in July, 2011 and will arrive near Ceres in February 2015. The end of the mission for Dawn is scheduled for February 2015.

Upon reaching Vesta, "Dawn" went into orbit around Vesta for closer studies of the asteroid whose size is about 330 miles in diameter. Vesta is thought to be part of the "main" asteroid belt between Mars and Jupiter. This is the first time for a spacecraft from earth to "visit" such a space object.


"Dawn will arrive near Ceres in February, 2015. Ceres is a dwarf planet first discovered in 1801 with a size of about 506 x 565 miles. The orbit of "Ceres" is within the main asteroid belt located between Mars and Jupiter.


"STARDUST" Mission

"Stardust" was the first space mission dedicated solely for exploration of a comet: Wild 2. Stardust's spacecraft was launched in February, 1999, and reached the comet in January 2004. Stardust captured "dust and carbon-based" samples as well as samples of intersteler "dust".

Prior to "Stardust", it was commonly though that comets were "dirty" snowballs but following the visit to Wild 2, NASA found that this comet had a ROCKY core similar to an asteroid with ice that had been formed in the deep regions of space beyond Neptune. Comets are different from asteroid in that comets eject "dust", forming a "tail" which always points away from the Sun.


"Deep Impact" Mission

This mission left earth on January 12, 2005, destined to rendezvous with comet 9P/Tempel 1 on July 1, 2005 and launch a projectile into the comet nucleus. The mission was so successful that it was assigned a new mission:

"EPOXI" Mission

The primary task of the Epoxi mission was to fly past comet Hartley 2 on November 4, 2010. Epoxi found that although Hartley 2 is smaller than Tempel 1, it is much more active.