Each of the two spacecraft was equipped with a slow-scan color TV camera to take images of the planets and their moons and each also carried an extensive suite of instruments to record magnetic, atmospheric, lunar, and other data about the planetary systems.
Fletcher announced that they would be renamed Voyager. Power was provided by three plutonium dioxide radioisotope thermoelectric generators RTGs mounted at the end of a boom. Voyager 2 began transmitting images of Jupiter April 24, , for time-lapse movies of atmospheric circulation.
During its encounter, it relayed back spectacular photos of the entire Jovian system, including its moons Callisto, Ganymede, Europa at a range of about , miles or , kilometers, much closer than Voyager 1 , Io, and Amalthea, all of which had already been surveyed by Voyager 1. When the earlier Pioneers flew by Jupiter, they detected few atmospheric changes from one encounter to the second, but Voyager 2 detected many significant changes, including a drift in the Great Red Spot as well as changes in its shape and color.
Following a course correction two hours after its closest approach to Jupiter, Voyager 2 sped to Saturn, its trajectory determined to a large degree by a decision made in January , to try to send the spacecraft to Uranus and Neptune later in the decade.
Its encounter with the sixth planet began Aug. Once again, Voyager 2 repeated the photographic mission of its predecessor, although it actually flew about 14, miles 23, kilometers closer to Saturn. The closest encounter to Saturn was at UT Aug.
Although Voyager 2 had fulfilled its primary mission goals with the two planetary encounters, mission planners directed the veteran spacecraft to Uranus—a journey that would take about 4. In fact, its encounter with Jupiter was optimized in part to ensure that future planetary flybys would be possible.
Long-range observations of the planet began Nov. Light conditions were times less than terrestrial conditions. Closest approach to Uranus took place at UT Jan. Its rings were found to be extremely variable in thickness and opacity. In flying by Miranda at a range of only 17, miles 28, kilometers , the spacecraft came closest to any object so far in its nearly decade-long travels. Images of the moon showed a strange object whose surface was a mishmash of peculiar features that seemed to have no rhyme or reason.
Uranus itself appeared generally featureless. The spectacular news of the Uranus encounter was interrupted the same week by the tragic Challenger accident that killed seven astronauts during their space shuttle launch Jan.
Following the Uranus encounter, the spacecraft performed a single midcourse correction Feb. It was the first human-made object to fly by the planet. Its 10 instruments were still in working order at the time.
During the encounter, the spacecraft discovered six new moons Proteus, Larissa, Despina, Galatea, Thalassa, and Naiad and four new rings. The planet itself was found to be more active than previously believed, with mile 1,kilometer per hour winds.
Hydrogen was found to be the most common atmospheric element, although the abundant methane gave the planet its blue appearance. Spectacular images of its southern hemisphere showed a strange, pitted cantaloupe-type terrain. Once past the Neptune system, Voyager 2 followed a course below the ecliptic plane and out of the solar system.
Of the four spacecraft sent out to beyond the environs of the solar system in the s, three of them -- Voyagers 1 and 2 and Pioneer 11 -- were all heading in the direction of the solar apex, i. In November , 21 years after launch, nonessential instruments were permanently turned off, leaving seven instruments still operating. For example, on Jan. During its six-month journey, the shock wave had plowed through the solar wind, sweeping up and accelerating charged particles.
The spacecraft provided important information on high-energy shock-energized ions. On Aug. By Nov. At this velocity, it would take about 19, years to traverse a single light-year. On July 8, , Voyager 2 successfully fired up its trajectory correction maneuver thrusters and will be using them to control the pointing of the spacecraft for the foreseeable future. Voyager 2 last used those thrusters during its encounter with Neptune in The spacecraft's aging attitude control thrusters have been experiencing degradation that required them to fire an increasing and untenable number of pulses to keep the spacecraft's antenna pointed at Earth.
Nov 05, Interactive 3D model of Voyager 2. View the full interactive experience at Eyes on the Solar System. Mars Cube One. Mid-Infrared Instrument. Galaxy Evolution Explorer. Kepler Exoplanet Mission. Wide Field and Planetary Camera 2. Viking 1. While the spacecraft is still operating — including sending health updates and science data that can be received by a series of smaller dishes also located in Australia — it has been unable to receive commands, ensuring that it will just keep doing whatever it was last doing until those new commands are received.
With its close flyby of Neptune and Triton, Voyager 2's trajectory was severely altered, plunging it On October 29, , enough of the upgrades had been executed that mission operators for Voyager 2 decided to perform a critical test: to send a series of commands to Voyager 2 for the first time since the upgrades began.
Although it takes about 36 light-hours for a signal to travel round-trip from Earth to Voyager 2, NASA announced on November 2 that the test was successful. Voyager 2 returned a signal that confirmed the call was received, followed by a successful execution of the commands. Triton, at left, as imaged by Voyager 2, and Pluto, at right, as imaged by New Horizons. Both worlds If Triton were returned to the Kuiper belt, it would be the largest, most massive body out there.
Voyager 2's encounter with Triton is the reason for its uniquely southerly trajectory. The upgrades to this member of the Deep Space Network are on track for completion in early , where they will not only be critical for the continued success of the Voyager 2 mission, but will prepare NASA for a series of upcoming missions. This particular dish was constructed in , where it had an original size of 64 meters feet.
It was expanded to 70 meters feet 15 years later, but none of the subsequent repairs or upgrades compare to the work being done today. Position and trajectory of Voyager 1 and the positions of the planets on 14 February , the day Both Voyager 1 and 2 are extremely out-of-the-plane of our Solar System now, with Voyager 1 to the north and Voyager 2 to the south.
Radio transmitters are needed in both hemispheres to contact them. As Voyager 2 and the other escaping spacecraft continue to recede from the Sun, their power levels will continue to drop and it will become progressively more difficult to issue commands to them as well as to receive data.
As long as these spacecraft remain operational in some capacity, simply continuing to upgrade our facilities here on Earth will enable us to gather data for years, and likely even decades, to come. Voyager 1 and 2 are already the most distant operational spacecraft ever launched from Earth, and continue to set new records.
This is a BETA experience. You may opt-out by clicking here. More From Forbes. Nov 10, , pm EST.
0コメント