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68-500: TerreStar was launched at 17:52 GMT on July 1, 2009, during a two-hour launch window that opened at 16:13. The launch occurred towards the end of the window due to bad weather in the first hour, followed by two aborted countdowns for launch attempts scheduled at 17:12 and 17:34. The launch was conducted by Arianespace , and used an Ariane 5ECA carrier rocket, flying from ELA-3 at the Guiana Space Centre . After launch,

136-480: A 50 km (31 mi)-deep ocean. Two new, small satellites, Adrastea and Metis , were found orbiting just outside the ring. A third new satellite, Thebe , was discovered between the orbits of Amalthea and Io. The closest approach to Saturn occurred at 03:24:05 UT on August 26, 1981. When Voyager 2 passed behind Saturn, viewed from Earth, it utilized its radio link to investigate Saturn's upper atmosphere, gathering data on both temperature and pressure. In

204-433: A Jupiter trajectory boost with an 825-kilogram (1,819 lb) payload, the spacecraft included a propulsion module made of a 1,123-kilogram (2,476 lb) solid-rocket motor and eight hydrazine monopropellant rocket engines, four providing pitch and yaw attitude control, and four for roll control. The propulsion module was jettisoned shortly after the successful Jupiter burn. Sixteen hydrazine Aerojet MR-103 thrusters on

272-530: A degree that allowed the scan platform to resume its function. Voyager 2 , which would have been diverted to perform the Titan flyby if Voyager 1 had been unable to, did not pass near Titan due to the malfunction, and subsequently, proceeded with its mission to explore the Uranian system. The closest approach to Uranus occurred on January 24, 1986, when Voyager 2 came within 81,500 km (50,600 mi) of

340-433: A distance of 1.7 light-years. If undisturbed for 296,000 years , Voyager 2 should pass by the star Sirius (8.6 light-years from Earth) at a distance of 4.3 light-years. Both Voyager space probes carry a gold-plated audio-visual disc , a compilation meant to showcase the diversity of life and culture on Earth in the event that either spacecraft is ever found by any extraterrestrial discoverer . The record, made under

408-586: A distance of 119.7 AU (11.1 billion mi; 17.9 billion km) from the Sun and moving at a velocity of 15.341 km/s (34,320 mph) relative to the Sun. Voyager 2 has left the Sun's heliosphere and is traveling through the interstellar medium , though still inside the Solar System , joining Voyager 1 , which had reached the interstellar medium in 2012. Voyager 2 has begun to provide

476-541: A frequency of 0.9-40 MHz. The UEDs were detected from 600,000 km of Uranus over 24 hours, most of which were not visible. However, microphysical modeling suggests that Uranian lightning occurs in convective storms occurring in deep troposphere water clouds. If this is the case, lightning will not be visible due to the thick cloud layers above the troposphere. Uranian lightning has a power of around 10 W, emits 1×10^7 J – 2×10^7 J of energy, and lasts an average of 120 ms. Detailed images from Voyager 2 ' s flyby of

544-654: A frequency range of 50 Hz – 12 kHz at magnetic latitudes 7˚-33˚. These plasma wave detections were possibly triggered by lightning over 20 minutes in the ammonia clouds of the magnetosphere. During Voyager 2 ' s closest approach to Neptune, the PWS instrument provided Neptune’s first plasma wave detections at a sample rate of 28,800 samples per second. The measured plasma densities range from 10 – 10 cm . Voyager 2 discovered previously unknown Neptunian rings , and confirmed six new moons: Despina , Galatea , Larissa , Proteus , Naiad and Thalassa . While in

612-455: A little short of Saturn's orbit of 9.5 AU (880 million mi; 1.42 billion km). Whereas, Voyager 2 ' s initial orbit had an aphelion of 6.2 AU (580 million mi; 930 million km), well short of Saturn's orbit. In April 1978, no commands were transmitted to Voyager 2 for a period of time, causing the spacecraft to switch from its primary radio receiver to its backup receiver. Sometime afterwards,

680-576: A major ground station antenna upgrade that took a year to complete. In October 2020, astronomers reported a significant unexpected increase in density in the space beyond the Solar System as detected by the Voyager 1 and Voyager 2 ; this implies that "the density gradient is a large-scale feature of the VLISM (very local interstellar medium ) in the general direction of the heliospheric nose ". On July 18, 2023, Voyager 2 overtook Pioneer 10 as

748-532: A movement had been formed by the NGO A Human Right to purchase TerreStar-1 and to use it to provide free basic Internet access to developing countries. The team was looking for US$ 150,000 in donations to put the first phase of their plan into action. However, after successfully bidding $ 1.375 billion for the acquisition of the TerreStar-1 satellite in a bankruptcy-court auction Dish Network on August 22, 2011 asked

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816-446: A planetary alignment occurring once in 175 years to visit Jupiter , Saturn , Uranus , and Neptune . When such an opportunity is missed, another target may be selected. For instance, ESA 's Rosetta mission was originally intended for comet 46P/Wirtanen , but a launcher problem delayed it and a new target had to be selected (comet 67P/Churyumov-Gerasimenko ). Launch periods are often calculated from porkchop plots , which show

884-432: A single probe to visit Jupiter , Saturn , Uranus , and Neptune by taking advantage of the then-new technique of gravity assists . NASA began work on a Grand Tour , which evolved into a massive project involving two groups of two probes each, with one group visiting Jupiter, Saturn, and Pluto and the other Jupiter, Uranus, and Neptune. The spacecraft would be designed with redundant systems to ensure survival throughout

952-537: Is equipped with three multihundred-watt radioisotope thermoelectric generators (MHW RTGs). Each RTG includes 24 pressed plutonium oxide spheres. At launch, each RTG provided enough heat to generate approximately 157 W of electrical power. Collectively, the RTGs supplied the spacecraft with 470 watts at launch (halving every 87.7 years). They were predicted to allow operations to continue until at least 2020, and continued to provide power to five scientific instruments through

1020-408: Is the time period on a given day during which a particular rocket must be launched in order to reach its intended target. If the rocket is not launched within a given window, it has to wait for the window on the next day of the period. Launch periods and launch windows are very dependent on both the rocket's capability and the orbit to which it is going. A launch period refers to the days that

1088-414: Is using to find out what the Solar System is like beyond the heliosphere . As of September 2023 Voyager 2 is transmitting scientific data at about 160 bits per second . Information about continuing telemetry exchanges with Voyager 2 is available from Voyager Weekly Reports. In 1992, Voyager 2 observed the nova V1974 Cygni in the far-ultraviolet, first of its kind. The further increase in

1156-697: The Deep Space Network on Earth. Communications are conducted over the S-band (about 13 cm wavelength) and X-band (about 3.6 cm wavelength) providing data rates as high as 115.2 kilobits per second at the distance of Jupiter, and then ever-decreasing as distance increases, because of the inverse-square law . When the spacecraft is unable to communicate with Earth , the Digital Tape Recorder (DTR) can record about 64 megabytes of data for transmission at another time. Voyager 2

1224-577: The Federal Communications Commission to let the company use the wireless spectrum of TerreStar to offer its own wireless broadband service. Despite its successful launch and groundbreaking achievements, TerreStar Corporation faced challenges and filed for Chapter 11 bankruptcy. In response, a movement led by the NGO A Human Right emerged, seeking to acquire TerreStar-1 and use it to provide free basic Internet access to developing countries. Their ambitious plan aimed to bridge

1292-593: The International Space Station were restricted by beta angle cutout. Beta angle ( β {\displaystyle \beta } ) is defined as the angle between the orbit plane and the vector from the Sun. Due to the relationship between an orbiting object's beta angle (in this case, the ISS) and the percent of its orbit that is spent in sunlight, solar power generation and thermal control are affected by that beta angle. Shuttle launches to

1360-420: The International Space Station , the launch window may be a single moment in time, known as an instantaneous launch window. Trajectories are programmed into a launch vehicle prior to launch. The launch vehicle will have a target, and the guidance system will alter the steering commands to attempt to get to the final end state. At least one variable (apogee, perigee, inclination, etc.) must be left free to alter

1428-578: The Jovian system in 1979, the Saturnian system in 1981, Uranian system in 1986, and the Neptunian system in 1989. The spacecraft is now in its extended mission of studying the interstellar medium . It is at a distance of 138.05  AU (20.7  billion   km ; 12.8 billion  mi ) from Earth as of October 2024 . The probe entered the interstellar medium on November 5, 2018, at

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1496-470: The delta-v needed to achieve the mission plotted against the launch time. The launch window is defined by the first launch point and ending launch point. It may be continuous (i.e. able to launch every second in the launch window) or may be a collection of discrete instantaneous points between the open and close. Launch windows and days are usually calculated in UTC and then converted to the local time of where

1564-476: The Attitude and Articulation Control Subsystem (AACS) along with redundant units of most instruments and 8 backup thrusters. The spacecraft also included 11 scientific instruments to study celestial objects as it traveled through space. Built with the intent for eventual interstellar travel, Voyager 2 included a large, 3.7 m (12 ft) parabolic, high-gain antenna ( see diagram ) to transceive data via

1632-458: The ISS were normally attempted only when the ISS was in an orbit with a beta angle of less than 60 degrees. Voyager 2 Voyager 2 is a space probe launched by NASA on August 20, 1977, as a part of the Voyager program . It was launched on a trajectory towards the gas giants Jupiter and Saturn and enabled further encounters with the ice giants Uranus and Neptune . It remains

1700-465: The Solar System's heliosphere is being pushed in. On April 22, 2010, Voyager 2 encountered scientific data format problems. On May 17, 2010, JPL engineers revealed that a flipped bit in an on-board computer had caused the problem, and scheduled a bit reset for May 19. On May 23, 2010, Voyager 2 resumed sending science data from deep space after engineers fixed the flipped bit. In 2013, it

1768-478: The Uranian moon Miranda showed huge canyons made from geological faults . One hypothesis suggests that Miranda might consist of a reaggregation of material following an earlier event when Miranda was shattered into pieces by a violent impact. Voyager 2 discovered two previously unknown Uranian rings. Measurements showed that the Uranian rings are different from those at Jupiter and Saturn. The Uranian ring system might be relatively young, and it did not form at

1836-517: The atmosphere of the moon was substantial and complex. Hence the trajectory was designed for optimum Titan flyby. Constructed by the Jet Propulsion Laboratory (JPL), Voyager 2 included 16 hydrazine thrusters, three-axis stabilization , gyroscopes and celestial referencing instruments (Sun sensor/ Canopus Star Tracker) to maintain pointing of the high-gain antenna toward Earth. Collectively these instruments are part of

1904-420: The brightness at those wavelengths helped in the more detailed study of the nova. In July 1994, an attempt was made to observe the impacts from fragments of the comet Comet Shoemaker–Levy 9 with Jupiter. The craft's position meant it had a direct line of sight to the impacts and observations were made in the ultraviolet and radio spectrum. Voyager 2 failed to detect anything, with calculations showing that

1972-479: The computer software in order to modify the functioning of the remaining thrusters to slow down the clogging of the small diameter hydrazine injector jets. Before uploading the software update on the Voyager 1 computer, NASA will first try the procedure with Voyager 2 , which is closer to Earth. The probe is expected to keep transmitting weak radio messages until at least the mid-2020s, more than 48 years after it

2040-425: The correct attitude of the spacecraft and to point its high-gain antenna in the direction of Earth are out of use due to clogging problems in their hydrazine injector. The spacecraft no longer has backups available for its thruster system and "everything onboard is running on single-string" as acknowledged by Suzanne Dodd, Voyager project manager at JPL , in an interview with Ars Technica . NASA has decided to patch

2108-440: The digital divide and connect underserved communities worldwide. However, Dish Network outbid others in the bankruptcy-court auction, acquiring TerreStar-1 for $ 1.375 billion. With this acquisition, Dish Network sought to utilize the satellite's wireless spectrum to offer its own wireless broadband service. Launch window In the context of spaceflight , launch period is the collection of days and launch window

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2176-962: The direction of a team including Carl Sagan and Timothy Ferris , includes photos of the Earth and its lifeforms, a range of scientific information, spoken greetings from people such as the Secretary-General of the United Nations and the President of the United States and a medley, "Sounds of Earth", that includes the sounds of whales, a baby crying, waves breaking on a shore, and a collection of music spanning different cultures and eras including works by Wolfgang Amadeus Mozart , Blind Willie Johnson , Chuck Berry and Valya Balkanska . Other Eastern and Western classics are included, as well as performances of indigenous music from around

2244-400: The early part of 2023. In April 2023 JPL began using a reservoir of backup power intended for an onboard safety mechanism. As a result, all five instruments had been expected to continue operation through 2026. In October 2024 NASA announced that the plasma science instrument had been turned off, preserving power for the remaining four instruments. Because of the energy required to achieve

2312-446: The entire day. For operational reasons, the window almost always is limited to no more than a few hours. The launch window can stretch over two calendar days (ex: start at 11:46 p.m. and end at 12:14 a.m.). Launch windows are sometimes but rarely exactly the same times each day. Launch windows and launch periods are often used interchangeably in the public sphere, even within the same organization. However, these definitions are

2380-603: The entire tour. By 1972 the mission was scaled back and replaced with two Mariner program -derived spacecraft, the Mariner Jupiter-Saturn probes. To keep apparent lifetime program costs low, the mission would include only flybys of Jupiter and Saturn, but keep the Grand Tour option open. As the program progressed, the name was changed to Voyager. The primary mission of Voyager 1 was to explore Jupiter, Saturn, and Saturn's largest moon, Titan . Voyager 2

2448-477: The features might be deep cracks, caused by crustal rifting or tectonic processes. Closer high-resolution photos from Voyager 2 , however, were puzzling: the features lacked topographic relief, and one scientist said they "might have been painted on with a felt marker". Europa is internally active due to tidal heating at a level about one-tenth that of Io. Europa is thought to have a thin crust (less than 30 km (19 mi) thick) of water ice, possibly floating on

2516-448: The fireballs were just below the craft's limit of detection. On November 29, 2006, a telemetered command to Voyager 2 was incorrectly decoded by its on-board computer—in a random error—as a command to turn on the electrical heaters of the spacecraft's magnetometer. These heaters remained turned on until December 4, 2006, and during that time, there was a resulting high temperature above 130 °C (266 °F), significantly higher than

2584-494: The first direct measurements of the density and temperature of the interstellar plasma . Voyager 2 remains in contact with Earth through the NASA Deep Space Network . Communications are the responsibility of Australia's DSS 43 communication antenna , located near Canberra . In the early space age, it was realized that a periodic alignment of the outer planets would occur in the late 1970s and enable

2652-538: The flyby. Following a course correction in 1987, Voyager 2 ' s closest approach to Neptune occurred on August 25, 1989. Through repeated computerized test simulations of trajectories through the Neptunian system conducted in advance, flight controllers determined the best way to route Voyager 2 through the Neptune–Triton system. Since the plane of the orbit of Triton is tilted significantly with respect to

2720-405: The highest regions of the atmosphere, where the pressure was measured at 70 mbar (1.0 psi), Voyager 2 recorded a temperature of 82  K (−191.2  °C ; −312.1  °F ). Deeper within the atmosphere, where the pressure was recorded to be 1,200 mbar (17 psi), the temperature rose to 143 K (−130 °C; −202 °F). The spacecraft also observed that the north pole

2788-404: The launch window occurs at the time of day when the launch site location is aligned with the plane of the required orbit. To launch at another time would require an orbital plane change maneuver which would require a large amount of propellant. For launches above low Earth orbit (LEO), the actual launch time can be somewhat flexible if a parking orbit is used, because the inclination and time

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2856-589: The magnetic field. Finally, in December 2018, Stone announced that Voyager 2 reached interstellar space on November 5, 2018. Maintenance to the Deep Space Network cut outbound contact with the probe for eight months in 2020. Contact was reestablished on November 2, when a series of instructions was transmitted, subsequently executed, and relayed back with a successful communication message. On February 12, 2021, full communications were restored after

2924-401: The magnetometers were designed to endure, and a sensor rotated away from the correct orientation. On August 30, 2007, Voyager 2 passed the termination shock and then entered into the heliosheath , approximately 1 billion mi (1.6 billion km) closer to the Sun than Voyager 1 did. This is due to the interstellar magnetic field of deep space. The southern hemisphere of

2992-493: The mission module provide attitude control. Four are used to execute trajectory correction maneuvers; the others in two redundant six-thruster branches, to stabilize the spacecraft on its three axes. Only one branch of attitude control thrusters is needed at any time. Thrusters are supplied by a single 70-centimeter (28 in) diameter spherical titanium tank. It contained 100 kilograms (220 lb) of hydrazine at launch, providing enough fuel until 2034. The Voyager 2 probe

3060-479: The moon Io , and revealed how the moon's surface had changed in the four months since the previous visit. Together, the Voyagers observed the eruption of nine volcanoes on Io, and there is evidence that other eruptions occurred between the two Voyager fly-bys. Jupiter's moon Europa displayed a large number of intersecting linear features in the low-resolution photos from Voyager 1 . At first, scientists believed

3128-494: The neighborhood of Neptune, Voyager 2 discovered the " Great Dark Spot ", which has since disappeared, according to observations by the Hubble Space Telescope . The Great Dark Spot was later hypothesized to be a region of clear gas, forming a window in the planet's high-altitude methane cloud deck. Once its planetary mission was over, Voyager 2 was described as working on an interstellar mission, which NASA

3196-535: The ones used by NASA (and other space agencies) launch directors and trajectory analysts. To go to another planet using the simple low-energy Hohmann transfer orbit , if eccentricity of orbits is not a factor, launch periods are periodic according to the synodic period ; for example, in the case of Mars, the period is 780 days (2.1 years). In more complex cases, including the use of gravitational slingshots , launch periods are irregular. Sometimes rare opportunities arise, such as when Voyager 2 took advantage of

3264-465: The only spacecraft to have visited either of the ice giant planets, and was the third of five spacecraft to achieve Solar escape velocity , which allowed it to leave the Solar System . Launched 16 days before its twin Voyager 1 , the primary mission of the spacecraft was to study the outer planets and its extended mission is to study interstellar space beyond the Sun's heliosphere . Voyager 2 successfully fulfilled its primary mission of visiting

3332-600: The plane of the ecliptic; through course corrections, Voyager 2 was directed into a path about 4,950 km (3,080 mi) above the north pole of Neptune. Five hours after Voyager 2 made its closest approach to Neptune, it performed a close fly-by of Triton , Neptune's largest moon, passing within about 40,000 km (25,000 mi). In 1989, the Voyager 2 Planetary Radio Astronomy (PRA) experiment observed around 60 lightning flashes, or Neptunian electrostatic discharges emitting energies over 7×10 J. A plasma wave system (PWS) detected 16 electromagnetic wave events with

3400-422: The planet's cloud tops. Jupiter's Great Red Spot was revealed as a complex storm moving in a counterclockwise direction. Other smaller storms and eddies were found throughout the banded clouds. Voyager 2 returned images of Jupiter, as well as its moons Amalthea , Io , Callisto , Ganymede , and Europa . During a 10-hour "volcano watch", it confirmed Voyager 1 ' s observations of active volcanism on

3468-484: The planet's cloudtops. Voyager 2 also discovered 11 previously unknown moons: Cordelia , Ophelia , Bianca , Cressida , Desdemona , Juliet , Portia , Rosalind , Belinda , Puck and Perdita . The mission also studied the planet's unique atmosphere, caused by its axial tilt of 97.8°; and examined the Uranian ring system . The length of a day on Uranus as measured by Voyager 2 is 17 hours, 14 minutes. Uranus

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3536-548: The primary receiver failed altogether. The backup receiver was functional, but a failed capacitor in the receiver meant that it could only receive transmissions that were sent at a precise frequency, and this frequency would be affected by the Earth's rotation (due to the Doppler effect ) and the onboard receiver's temperature, among other things. Voyager 2 ' s closest approach to Jupiter occurred at 22:29 UT on July 9, 1979. It came within 570,000 km (350,000 mi) of

3604-522: The rocket and spacecraft operators are located (frequently multiple time zones for USA launches). For trips into largely arbitrary Earth orbits , no specific launch time is required. But if the spacecraft intends to rendezvous with an object already in orbit, the launch must be carefully timed to occur around the times that the target vehicle's orbital plane intersects the launch site. Earth observation satellites are often launched into sun-synchronous orbits which are near-polar . For these orbits,

3672-453: The rocket can launch to reach its intended orbit. A mission could have a period of 365 days in a year, a few weeks each month, a few weeks every 26 months (e.g. Mars launch periods ), or a short period time that won't be repeated. A launch window indicates the time frame on a given day in the launch period that the rocket can launch to reach its intended orbit. This can be as short as a second (referred to as an instantaneous window) or even

3740-407: The same time that Uranus did. The particles that make up the rings might be the remnants of a moon that was broken up by either a high-velocity impact or torn up by tidal effects . In March 2020, NASA astronomers reported the detection of a large atmospheric magnetic bubble, also known as a plasmoid , released into outer space from the planet Uranus , after reevaluating old data recorded during

3808-458: The satellite separated from the carrier rocket into a geosynchronous transfer orbit . It will subsequently raise itself into geostationary orbit by means of its onboard propulsion system. It will be positioned at 111° West longitude , and is expected to operate for 15 years. A second satellite, TerreStar-2 (now EchoStar XXI ), was launched on 2017, positioned at 10E, and owned by Echostar. Following TerreStar's filing for Chapter 11 bankruptcy,

3876-460: The second farthest spacecraft from the Sun. On July 21, 2023, a programming error misaligned Voyager 2 's high gain antenna 2 degrees away from Earth, breaking communications with the spacecraft. By August 1, the spacecraft's carrier signal was detected using multiple antennas of the Deep Space Network . A high-power "shout" on August 4 sent from the Canberra station successfully commanded

3944-505: The spacecraft initially spends in the parking orbit can be varied. See the launch window used by the Mars Global Surveyor spacecraft to the planet Mars at [1] . Achieving the correct orbit requires the right ascension of the ascending node (RAAN). RAAN is set by varying a launch time, waiting for the earth to rotate until it is in the correct position. For missions with very specific orbits, such as rendezvousing with

4012-570: The spacecraft to reorient towards Earth, resuming communications. As a failsafe measure, the probe is also programmed to autonomously reset its orientation to point towards Earth, which would have occurred by October 15. As the power from the RTG slowly reduces, various items of equipment have been turned off on the spacecraft. The first science equipment turned off on Voyager 2 was the PPS in 1991, which saved 1.2 watts. Some thrusters needed to control

4080-506: The values of the others, otherwise the dynamics would be overconstrained . An instantaneous launch window allows the RAAN be the uncontrolled variable. While some spacecraft, such as the Centaur upper stage , can steer and adjust its RAAN after launch, choosing an instantaneous launch window allows the RAAN to be pre-determined for the spacecraft's guidance system. Space Shuttle missions to

4148-436: Was also found to radiate large amounts of ultraviolet light, a phenomenon that is called "dayglow". The average atmospheric temperature is about 60 K (−351.7 °F; −213.2 °C). The illuminated and dark poles, and most of the planet, exhibit nearly the same temperatures at the cloud tops. The Voyager 2 Planetary Radio Astronomy (PRA) experiment observed 140 lightning flashes, or Uranian electrostatic discharges with

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4216-451: Was also to explore Jupiter and Saturn, but on a trajectory that would have the option of continuing on to Uranus and Neptune, or being redirected to Titan as a backup for Voyager 1 . Upon successful completion of Voyager 1 's objectives, Voyager 2 would get a mission extension to send the probe on towards Uranus and Neptune. Titan was selected due to the interest developed after the images taken by Pioneer 11 in 1979, which had indicated

4284-426: Was approximately 10 °C (18 °F) cooler at 100 mbar (1.5 psi) than mid-latitudes, a variance potentially attributable to seasonal shifts ( see also Saturn Oppositions ). After its Saturn fly-by, Voyager 2 ' s scan platform experienced an anomaly causing its azimuth actuator to seize. This malfunction led to some data loss and posed challenges for the spacecraft's continued mission. The anomaly

4352-496: Was launched on August 20, 1977, by NASA from Space Launch Complex 41 at Cape Canaveral, Florida , aboard a Titan IIIE / Centaur launch vehicle . Two weeks later, the twin Voyager 1 probe was launched on September 5, 1977. However, Voyager 1 reached both Jupiter and Saturn sooner, as Voyager 2 had been launched into a longer, more circular trajectory. Voyager 1 ' s initial orbit had an aphelion of 8.9 AU (830 million mi; 1.33 billion km), just

4420-507: Was launched. NASA says that "The Voyagers are destined—perhaps eternally—to wander the Milky Way." Voyager 2 is not headed toward any particular star. The nearest star is 4.2 light-years away, and at 15.341 km/s, the spacecraft travels one light-year in about 19,541 years - during which time the nearby stars will also move substantially. In roughly 42,000 years, Voyager 2 will pass the star Ross 248 (10.30 light-years away from Earth) at

4488-460: Was originally thought that Voyager 2 would enter interstellar space in two to three years, with its plasma spectrometer providing the first direct measurements of the density and temperature of the interstellar plasma. But the Voyager project scientist, Edward C. Stone and his colleagues said they lacked evidence of what would be the key signature of interstellar space: a shift in the direction of

4556-453: Was shown to have a magnetic field that was misaligned with its rotational axis, unlike other planets that had been visited to that point, and a helix-shaped magnetic tail stretching 10 million kilometers (6 million miles) away from the Sun. When Voyager 2 visited Uranus, much of its cloud features were hidden by a layer of haze; however, false-color and contrast-enhanced images show bands of concentric clouds around its south pole. This area

4624-402: Was traced back to a combination of issues, including a design flaw in the actuator shaft bearing and gear lubrication system, corrosion, and debris build-up. While overuse and depleted lubricant were factors, other elements, such as dissimilar metal reactions and a lack of relief ports, compounded the problem. Engineers on the ground were able to issue a series of commands, rectifying the issue to

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