ပိုင်အိုနီးယား-၁၀ အာကာသယာဉ်

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ဤနေရာသို့သွားရန် - အ​ညွှန်း​, ရှာ​ဖွေ​ရန်​
Pioneer 10
Pioneer 10-11 spacecraft.jpg
Pioneer 10
Operator ARC / NASA
Major contractors TRW
Mission type Flyby
Flyby of Jupiter
Launch date 1972-03-02 01:49:00 UTC
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Launch vehicle Atlas/Centaur/TE364-4
Launch site Space Launch Complex 36A
Cape Canaveral Air Force Station
Mission duration March 2, 1972 – January 23, 2003
(30 years, 10 months, 22 days)
(lost communication)
Mission highlight Jupiter flyby
Template:Pad(completed 1974-01-01)
Interstellar mission
Template:Pad(completed 1997-03-31)
COSPAR ID 1972-012A
Homepage Pioneer Project website(archived)
NASA Archive page
Mass includeonly>၂၅၈ kg (includeonly>၅၇၀ lb)
Power 155.0 W (4 SNAP-19 RTGs)

ပိုင်အိုနီးယား ၁၀အာကာသယာဉ်သည် ၂၅၈ ကီလိုဂရမ်အလေးချိန်ရှိသည့် အာကာသစူးစမ်းလေ့လာရေးစက်ရုပ်ယာဉ်ဖြစ်သည်။ ဂျူပီတာဂြိုဟ်သို့ပထမဆုံးခရီးနှင်ခဲ့ပြီး နေအဖွဲ့အစည်းမှ လွတ်မြောက်အလျင်ဖြင့်ထွက်ခွာနိုင်ခဲ့သောပထမဆုံးယာဉ်ဖြစ်သည်။ စီမံကိန်းကို အမေရိကန်အမျိုးသားလေကြောင်းနှင့်အာကာသစီမံမှုအဖွဲ့(နာဆာ)၏ အမ်းစ်သုတေသနဌာနက ကိုင်တွယ်ခဲ့ပြီး TRW Inc က ယာဉ်ကိုပုံစံထုတ်ခဲ့သည်။ ပိုင်အိုနီးယား ၁၀ ကို အချင်း၂.၇၄ မီတာရှိသည့်စလောင်း၊ ယင်းတွင်ဆက်စပ်တပ်ဆင်ထားသည့် ဆဌဂံပုံကိုယ်ထည်၊ ဖမ်းယူမှုမြင့်မားသည်အင်တင်နာချောင်းကြီးတစ်ချောင်းတို့ဖြင့်ဖွဲ့စည်းထားသည်။ လိုအပ်သည့်စွမ်းအင်ကို ရေဒီယိုအိုင်ဆိုတုပ် အပူလျှပ်စစ်ဓာတ်အားထုတ်စက်လေးခုပေါင်းမှ စတင်ပစ်လွှတ်ချိန်တွင် ၁၅၅ ဝပ်ရရှိသည်။

ပိုင်အိုနီးယား ၁၀ ကို ၁၉၇၂ခုနှစ် မတ်လ၂ရက်နေ့တွင် ဖလော်ရီဒါရှိ ကိပ်ကာနီဗယ်အာကာသလွှတ်တင်ရေးစခန်းမှလွှတ်တင်ခဲ့သည်။ ဇွန် ၁၅ ရက်နေ့တွင် ဂြိုဟ်သိမ်ဂြိုဟ်မွှားများပတ်လမ်းကိုဖြတ်သွားသော ပထမဆုံးအာကာသယာဉ်ဖြစ်လာသည်။ ၁၉၇၃၊ နိုဝင်ဘာ ၆ ရက်မှစတင်၍ ကီလိုမီတာ၂၅သန်းအကွာအဝေးမှ ဂျူပီတာဂြိုဟ်၏ဓာတ်ပုံများကို စတင်ပေးပို့ခဲ့သည်။ စုစုပေါင်းဓာတ်ပုံ ၅၀၀ ကျော်ပေးပို့ခဲ့သည်။ ၁၉၇၃၊ ဒီဇင်ဘာတွင် ဂြိုဟ်နှင့်အနီးဆုံး ၁၃၂, ၂၅၂ ကီလိုမီတာအကွာသို့ရောက်ရှိခဲ့သည်။ ခရီးစဉ်တွင် ယာဉ်ပေါ်တွင်တပ်ဆင်ပေးလိုက်သောကိရိယာများသည် ဂြိုဟ်သိမ်ဂြိုဟ်မွှားပတ်လမ်းခါးပတ်ကွင်း၊ ဂျူပီတာဂြိုဟ်ပတ်ဝန်းကျင်၊ နေမုန်တိုင်းများ၊ အာကာသရောင်ခြည်များကိုလေ့လာနိုင်ခဲ့သည်။ ယခုအခါနေစကြာဝဠာအတွင်းအစွန်ဆုံးရှိ ဟေလီယိုစပီးယားအလွှာ(နေစကြာဝဠာနယ်နိမိတ်အစွန်)သို့ရောက်ရှိနေပြီဖြစ်သည်။ ၂၀၀၃၊ ဇန္နဝါရီ ၂၃တွင် ကမ္ဘာမှ ကီလိုမီတာ၁၂ဘီလျံ(၈၀အာကာသယူနစ်)အရောက်တွင် ယာဉ်ပေါ်တွင်ဓာတ်အားနည်းပါးလာမှုကြောင့် ဆက်သွယ်မှုပြတ်တောက်ခဲ့သည်။

Mission background[ပြင်​ဆင်​ရန်​]

History[ပြင်​ဆင်​ရန်​]

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ပိုင်အိုးယား ၁၀ ယာဉ်အားနောက်ဆုံးအဆင့်တပ်ဆင်နေပုံ
Pioneer 10 on a kick motor just prior to being encapsulated for launch

In the 1960s, American aerospace engineer Gary Flandro of the NASA Jet Propulsion Laboratory conceived of a mission, known as the Planetary Grand Tour, that would exploit a rare alignment of the outer planets of the Solar System. This mission would ultimately be accomplished in the late 1970s by the two Voyager probes, but in order to prepare for it, NASA decided in 1964 to experiment with launching a pair of probes to the outer Solar System.Template:Sfn An advocacy group named the Outer Space Panel and chaired by American space scientist James A. Van Allen, worked out the scientific rationale for exploring the outer planets.Template:SfnTemplate:Sfn Goddard put together a proposal for a pair of "Galactic Jupiter Probes" that would pass through the asteroid belt and visit Jupiter. These were to be launched in 1972 and 1973 during favorable windows that occurred only a few weeks every 13 months. Launch during other time intervals would have been more costly in terms of propellant requirements.Template:Sfn

Approved by NASA in February 1969,Template:Sfn the twin spacecraft were designated Pioneer F and Pioneer G before launch; later they were named Pioneer 10 and Pioneer 11. They formed part of the Pioneer program,Template:Sfn a series of United States unmanned space missions launched between 1958 and 1978. This model was the first in the series to be designed for exploring the outer solar system. Based on multiple proposals issued throughout the 1960s, the early mission objectives were to explore the interplanetary medium past the orbit of Mars, study the asteroid belt and assess the possible hazard to spacecraft traveling through the belt, and explore Jupiter and its environment.[၁] Later development-stage objectives included the probe closely approaching Jupiter to provide data on the effect the environmental radiation surrounding Jupiter would have on the spacecraft instruments.

More than 150 scientific experiments were proposed for the missions.Template:Sfn The experiments to be carried on the spacecraft were selected in a series of planning sessions during the 1960s, then were finalized by early 1970. These would be to perform imaging and polarimetry of Jupiter and several of its satellites, make infrared and ultraviolet observations of Jupiter, detect asteroids and meteoroids, determine the composition of charged particles, and to measure magnetic fields, plasma, cosmic rays and the Zodiacal Light.[၁] Observation of the spacecraft communications as it passed behind Jupiter would allow measurements of the planetary atmosphere, while tracking data would improve estimates of the mass of Jupiter and its moons.[၁]

NASA Ames Research Center, rather than Goddard, was selected to manage the project as part of the Pioneer program.Template:Sfn Ames, under the management of Charles F. Hall, was chosen because of their previous experience with spin-stabilized spacecraft. The requirements called for a small, lightweight spacecraft that was magnetically clean and could perform an interplanetary mission. It was to use spacecraft modules that had already been proven in the Pioneer 6 through 9 missions.[၁]

In February 1970, Ames awarded a combined $380 million contract to TRW for building both the Pioneer 10 and Pioneer 11 vehicles, bypassing the bidding process to save time. B. J. O'Brien and Herb Lassen led the TRW team that assembled the spacecraft.Template:Sfn Design and construction of the spacecraft required an estimated 25 million person-hours.Template:Sfn

To meet the schedule, the first launch would need to take place between February 29 and March 17 so that it could arrive at Jupiter in November 1974. This was later revised to an arrival date of December 1973 in order to avoid conflicts with other missions over the use of the Deep Space Network for communications, and to miss the period when Earth and Jupiter would be at opposite sides of the Sun. The encounter trajectory for Pioneer 10 was selected to maximize the information returned about the radiation environment around Jupiter, even if this caused damage to some systems. It would come within about three times the radius of the planet, which was thought to be the closest it could approach and still survive the radiation. The trajectory chosen would give the spacecraft a good view of the sunlit side.Template:Sfn

ယာဉ်ဒီဇိုင်း[ပြင်​ဆင်​ရန်​]

ပိုင်အိုနီးယား ၁၀ နှင့် ၁၁ အာကာသယာဉ်များပုံ

The Pioneer 10 bus measures Template:Convert/cm deep and with six Template:Convert/cm long panels forming the hexagonal structure. The bus houses propellant to control the orientation of the probe and eight of the eleven scientific instruments. The equipment compartment lies within an aluminum honeycomb structure to provide protection from meteoroids. A layer of insulation, consisting of aluminized mylar and kapton blankets, provides passive thermal control. Heat is generated by the dissipation of 70 to 120 watts (W) from the electrical components inside the compartment. The heat range is maintained within the operating limits of the equipment by means of louvers located below the mounting platform.[၂] The spacecraft had a launch mass of includeonly>၂၆၀ kilograms (includeonly>၅၇၀ lb).[၃]Template:Rp

At launch, the spacecraft carried includeonly>၃၆ kilograms (includeonly>၇၉ lb) of liquid hydrazine monopropellant in a Template:Convert/cm diameter spherical tank.[၂] Orientation of the spacecraft was maintained with six 4.5 N,[၄] hydrazine thrusters mounted in three pairs. Pair one maintained a constant spin-rate of 4.8-rpm, pair two controlled the forward thrust, and pair three controlled the attitude. The attitude pair were used in conical scanning maneuvers to track Earth in its orbit.[၅] Orientation information was also provided by a star sensor able to reference Canopus, and two sun sensors.Template:Sfn

Power and communications[ပြင်​ဆင်​ရန်​]

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Two of the SNAP-19 RTGs mounted on an extension boom
Testing spin rotation centered along the main communication dish axis

Pioneer 10 used four SNAP-19 radioisotope thermoelectric generators (RTG). They were positioned on 2 three-rod trusses, each includeonly>၃ metres (includeonly>၉.၈ ft) in length and 120 degrees apart. This was expected to be a safe distance from the sensitive scientific experiments carried on board. Combined, the RTGs provided 155 W at launch, and decayed to 140 W in transit to Jupiter. The spacecraft required 100 W to power all systems.[၃]Template:Rp The generators were powered by the radioisotope fuel plutonium-238, which was housed in a multi-layer capsule protected by a graphite heat shield.[၆]

The pre-launch requirement for the SNAP-19 was to provide power for two years in space; this was greatly exceeded during the mission.[၇] The plutonium-238 has a half-life of 87.74 years, so that after 29 years the radiation being generated by the RTGs was at 80% of its intensity at launch. However, steady deterioration of the thermocouple junctions led to a more rapid decay in electrical power generation, and by 2005 the total power output was 65 W. As a result, later in the mission only selected instruments could be operated at any one time.[၂]

The space probe includes a redundant system of transceivers, one attached to the narrow-beam, high-gain antenna, the other to an omni-antenna and medium-gain antenna. The parabolic dish for the high-gain antenna is includeonly>၂.၇၄ metres (includeonly>{{rnd/cExpression error: Unexpected < operator.decExpression error: Unexpected < operator.|Expression error: Unexpected < operator.|(Expression error: Unexpected < operator.)}} ft) in diameter and made from an aluminum honeycomb sandwich material. The spacecraft is spun about an axis that is parallel to the axis of this antenna so that it can remain oriented toward the Earth.[၂] Each transceiver is 8 W and transmits data across the S-band using 2110 MHz for the uplink from Earth and 2292 MHz for the downlink to Earth with the Deep Space Network tracking the signal. Data to be transmitted was passed through a convolutional encoder so that most communication errors could be corrected by the receiving equipment on Earth.[၃]Template:Rp The data transmission rate at launch was 256 bit/s, with the rate degrading by about −1.27 millibit/s for each day during the mission.[၂]

Much of the computation for the mission was performed on Earth and transmitted to the probe, where it was able to retain in memory, up to five commands of the 222 possible entries by ground controllers. The spacecraft included two command decoders and a command distribution unit, a very limited form of processor, to direct operations on the spacecraft. This system required that mission operators prepare commands long in advance of transmitting them to the probe. A data storage unit was included to record up to 6,144 bytes of information gathered by the instruments. The digital telemetry unit was used to prepare the collected data in one of the thirteen possible formats before transmitting it back to Earth.[၃]Template:Rp

သိပ္ပံပစ္စည်းများ[ပြင်​ဆင်​ရန်​]

Helium Vector Magnetometer (HVM)
Pioneer 10-11 - P50 - fx.jpg

This instrument measures the fine structure of the interplanetary magnetic field, maps the Jovian magnetic field, and provides magnetic field measurements to evaluate solar wind interaction with Jupiter. The magnetometer consists of a helium-filled cell mounted on a 6.6–m boom to partly isolate the instrument from the spacecraft's magnetic field.[၈]


Quadrispherical Plasma Analyzer
Pioneer 10-11 - P51b - fx.jpg

Peers through a hole in the large dish-shaped antenna to detect particles of the solar wind originating from the Sun.[၉]


Charged Particle Instrument (CPI)
Pioneer 10-11 - P52a - fx.jpg

Detects cosmic rays in the Solar System.[၁၀]


Cosmic Ray Telescope (CRT)
Pioneer 10-11 - P52b - fx.jpg

Collects data on the composition of the cosmic ray particles and their energy ranges.[၁၁]


Geiger Tube Telescope (GTT)
Template:Center

Surveys the intensities, energy spectra, and angular distributions of electrons and protons along the spacecraft's path through the radiation belts of Jupiter.[၁၂]


Trapped Radiation Detector (TRD)
Pioneer 10-11 - P54 - fx.jpg

Includes an unfocused Cerenkov counter that detects the light emitted in a particular direction as particles pass through it recording electrons of energy, 0.5 to 12 MeV, an electron scatter detector for electrons of energy, 100 to 400 keV, and a minimum ionizing detector consisting of a solid-state diode that measures minimum ionizing particles (<3 MeV) and protons in the range of 50 to 350 MeV.[၁၃]


Meteoroid Detectors
Pioneer 10-11 - P56 - fx.jpg

Twelve panels of pressurized cell detectors mounted on the back of the main dish antenna record penetrating impacts of small meteoroids.[၁၄]


Asteroid/Meteoroid Detector (AMD)
Pioneer 10-11 - P55b - fx.jpg

Meteoroid-asteroid detector looks into space with four non-imaging telescopes to track particles ranging from close-by bits of dust to distant large asteroids.[၁၅]


Ultraviolet Photometer
Pioneer 10-11 - P57a - fx.jpg

Ultraviolet light is sensed to determine the quantities of hydrogen and helium in space and on Jupiter.[၁၆]


Imaging Photopolarimeter (IPP)
Pioneer 10-11 - P60 - fx.jpg

The imaging experiment relies upon the spin of the spacecraft to sweep a small telescope across the planet in narrow strips only 0.03 degrees wide, looking at the planet in red and blue light. These strips were then processed to build up a visual image of the planet.[၁၇]


Infrared Radiometer
P58 - fx.jpg

Provides information on cloud temperature and the output of heat from Jupiter.[၁၈]

  • Principal investigator: Andrew Ingersoll / California Institute of TechnologyTemplate:Sfn

Pioneer plaque[ပြင်​ဆင်​ရန်​]


Pioneer Plaque

At the behest of Carl Sagan,Template:Sfn Pioneer 10 and Pioneer 11 carry a Template:Convert/by gold-anodized aluminum plaque in case either spacecraft is ever found by intelligent life-forms from another planetary system. The plaques feature the nude figures of a human male and female along with several symbols that are designed to provide information about the origin of the spacecraft.[၁၉] The plaque is attached to the antenna support struts to provide some shielding from interstellar dust.

Mission profile[ပြင်​ဆင်​ရန်​]

Launch and trajectory[ပြင်​ဆင်​ရန်​]

The launch of Pioneer 10
Pioneer 10 interplanetary trajectory

The Pioneer 10 probe was launched on March 3, 1972 at 01:49:00 UTC (March 2 local time) by the National Aeronautics and Space Administration from Space Launch Complex 36A at Cape Canaveral, Florida aboard an Atlas/Centaur launch vehicle. The third stage consisted of a solid fuel TE364-4 developed specifically for the Pioneer missions. This stage provided about 15,000 pounds of thrust and spun up the spacecraft.[၂၀] The spacecraft had an initial spin rate of 30 revolutions per minute. Twenty minutes following the launch, the vehicle's three booms were extended, which slowed the rotation rate to 4.8 per minute. This rate was maintained throughout the voyage. The launch vehicle accelerated the probe for net interval of 17 minutes, reaching a velocity of 51,682 kilometers/hour (32,114 miles/hour).Template:Sfn

After the high-gain antenna was contacted, several of the instruments were activated for testing while Pioneer 10 was moving through the Earth's radiation belts. Ninety minutes after launch, the spacecraft reached interplanetary space.Template:Sfn Pioneer 10 passed by the Moon in 11 hoursTemplate:Sfn and become the fastest man-made object at that time.Template:Sfn Two days after launch, the scientific instruments were turned on, beginning with the cosmic ray telescope. After ten days, all of the instruments were active.Template:Sfn

During the first seven months of the journey, the spacecraft made three course corrections. The on-board instruments underwent checkouts, with the photometers examining Jupiter and the Zodiacal light, and experiment packages being used to measure cosmic rays, magnetic fields and the solar wind. The only anomaly during this interval was the failure of the star sensor, which instead required the spacecraft to maintain its orientation using the two sun sensors.Template:Sfn

While passing through interplanetary medium, Pioneer 10 became the first mission to detect interplanetary atoms of helium. It also observed high-energy ions of aluminum and sodium in the solar wind. On July 15, 1972, Pioneer 10 was the first spacecraft to enter the asteroid belt, located between the orbits of Mars and Jupiter. The project planners expected a safe passage through the belt, and the closest the trajectory would take Pioneer 10 to any of the known asteroids was 8.8 × 106 km (5.5 × 106 mi). One of the nearest approaches was to the asteroid 307 Nike on December 2, 1972.Template:Sfn

The on-board experiments demonstrated a deficiency of particles below a micrometer (μm) in the belt, as compared to the vicinity of the Earth. The density of dust particles between 10–100 μm did not vary significantly during the trip from the Earth to the outer edge of the belt. Only for particles with a diameter of 100 μm to 1.0 mm did the density show an increase, by a factor of three-fold in the region of the belt. No fragments larger than a millimeter were observed in the belt, indicating these are likely rare; certainly much less common than anticipated. As the spacecraft did not collide with any particles of substantial size, it passed safely through the belt, emerging on the other side about February 15, 1973.[၂၁]Template:Sfn

Encounter with Jupiter[ပြင်​ဆင်​ရန်​]

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Pioneer 10 trajectory through the Jovian system
Pioneer 10 image of Jupiter showing the Great Red Spot near the right limb
The moon Ganymede as imaged by Pioneer 10

On November 6, 1973, the Pioneer 10 spacecraft was at a distance of 25 million km from Jupiter. Testing of the imaging system began, and the data was successfully received back at the Deep Space Network. A series of 16,000 commands were then uploaded to the spacecraft to control the fly-by operations during next 60 days. The orbit of the outer moon Sinope was crossed on November 8. The bow shock of Jupiter's magnetosphere was reached on November 16, as indicated by a drop in the velocity of the solar wind from 451 km/s to 225 km/s. The magnetopause was passed through a day later. The spacecraft instruments confirmed that the magnetic field of Jupiter was inverted compared to that of Earth. By the 29th, the orbits of all of the outermost moons had been passed and the spacecraft was operating flawlessly.Template:Sfn

Red and blue pictures of Jupiter were being generated by the imaging photopolarimeter as the rotation of the spacecraft carried the instrument's field of view past the planet. These red and blue colors were combined to produce a synthetic green image, allowing a three-color combination to produce the rendered image. On November 26, a total of twelve such images were received back on Earth. By December 2, the image quality exceeded the best images made from Earth. These were being displayed in real-time back on Earth, and the Pioneer Program would later receive an Emmy award for this presentation to the media. The motion of the spacecraft produced geometric distortions that later had to be corrected by computer processing.Template:Sfn During the encounter, a total of more than 500 images were transmitted.Template:Sfn

The trajectory of the spacecraft took it along the magnetic equator of Jupiter, where the ion radiation was concentrated.Template:Sfn Peak flux for this electron radiation is 10,000 times stronger than the maximum radiation around the Earth.Template:Sfn Starting on December 3, the radiation around Jupiter caused false commands to be generated. Most of these were corrected by contingency commands, but the Io image and a few close ups of Jupiter were lost. Similar false commands would be generated on the way out from the planet. Template:Sfn Nonetheless, Pioneer 10 did succeed in obtaining images of the moons Ganymede and Europa. The image of Ganymede showed low albedo features in the center and near the south pole, while the north pole appeared brighter. Europa was too far away to obtain a detailed image, although some albedo features were apparent.Template:Sfn

The trajectory of Pioneer 10 was chosen to take it behind Io, allowing the refractive effect of the moon's atmosphere on the radio transmissions to be measured. This demonstrated that the ionosphere of the moon was about 700 km above the surface on the day side, and the density ranged from 60,000 electrons per cubic centimeter on the day side, down to 9,000 on the night face. An unexpected discovery was that Io was orbiting within a cloud of hydrogen that extended for about 805,000 km, with a width and height of 402,000 km. A smaller, 110,000 km cloud was believed to have been detected about Europa.Template:Sfn

At the closest approach, the velocity of the spacecraft reached 132,000 km/h.Template:Sfn The spacecraft came within 132,252 km of the outer atmosphere of Jupiter. Close-in images of the Great Red Spot and the terminator were obtained. Communication with the spacecraft then ceased as it passed behind the planet.Template:Sfn The occultation data allowed the temperature structure of the outer atmosphere to be measured, showing a temperature inversion between the altitudes with 10 and 100 mbar pressures. Temperatures at the 10 mbar level ranged from -133° to -113°C, while temperatures at the 100 mbar level were -183° to -163°C.Template:Sfn The spacecraft generated an infrared map of the planet, which confirmed the idea that the planet radiated more heat than it received from the Sun.Template:Sfn

Crescent images of the planet were then returned as Pioneer 10 moved away from the planet.Template:Sfn As the spacecraft headed outward, it again passed the bow shock of Jupiter's magnetosphere. As this front is constantly shifting in space because of dynamic interaction with the solar wind, the vehicle crossed the bow shock a total of 17 times before it escaped completely.Template:Sfn

Deep space[ပြင်​ဆင်​ရန်​]

An artist's depiction of Pioneer 10 in the outer solar system

Pioneer 10 crossed the orbit of Saturn in 1976 and the orbit of Uranus in 1979.Template:Sfn On June 13, 1983, Pioneer 10 crossed the orbit of Neptune, becoming the first man-made object to leave the proximity of the major planets of our solar system. The mission came to an official end on March 31, 1997, when it had reached a distance of 67 AU from the Sun, though the spacecraft was still able to transmit coherent data after this date.[၂]

Analysis of the radio tracking data from the Pioneer 10 and 11 spacecraft at distances between 20–70 AU from the Sun has consistently indicated the presence of a small but anomalous Doppler frequency drift. The drift can be interpreted as due to a constant acceleration of (8.74 ± 1.33) × 10−10 m/s2 directed towards the Sun. Although it is suspected that there is a systematic origin to the effect, none was found. As a result, there is sustained interest in the nature of this so-called "Pioneer anomaly".[၂၂] Extended analysis of mission data by Slava Turyshev and colleagues has determined the source of the anomaly to be asymmetric thermal radiation.[၂၃] In July 2012, the Pioneer anomaly was explained as a thermal recoil force (heat escaping) acting on the face of the Pioneers away from the Sun.[၂၄]

After March 31, 1997, Pioneer 10's weak signal continued to be tracked by the Deep Space Network to aid the training of flight controllers in the process of acquiring deep space radio signals. There was an Advanced Concepts study applying chaos theory to extract coherent data from the fading signal.[၂၅]

The last successful reception of telemetry was received from Pioneer 10 on April 27, 2002; subsequent signals were barely strong enough to detect, and provided no usable data. The final, very weak signal from Pioneer 10 was received on January 23, 2003 when it was 12 billion kilometers (80 AU) from Earth.[၂၆] Further attempts to contact the spacecraft were unsuccessful. The final attempt was made on the evening of March 4, 2006, the last time the antenna would be correctly aligned with Earth. No response was received from Pioneer 10.[၂၇] NASA decided that the RTG units had probably fallen below the power threshold needed to operate the transmitter. Hence, no further attempts at contact were made.Template:Sfn

Timeline[ပြင်​ဆင်​ရန်​]

Timeline of travel
Date Event
Template:Center Spacecraft launched
Template:Center Crossed orbit of Mars.
Template:Center Entered the asteroid belt.
Template:Center Start Jupiter observation phase.
Time Event
Template:Center Encounter with Jovian system
Template:Center Callisto flyby at 1,392,300 km
Template:Center Ganymede flyby at 446,250 km
Template:Center Europa flyby at 321,000 km
Template:Center Io flyby at 357,000 km
Template:Center
Template:Center Jupiter closest approach at 200,000 km
Template:Center Jupiter equator plane crossing
Template:Center Io occultation entry
Template:Center Io occultation exit
Template:Center Jupiter occultation entry
Template:Center Jupiter shadow entry
Template:Center Jupiter occultation exit
Template:Center Jupiter shadow exit
Template:Center Phase stop.
Template:Center Begin Pioneer Interstellar Mission.
More
Template:Center The US Post Office issued a commemorative stamp featuring the Pioneer 10 space probe (See image).
Template:Center Crossed orbit of Pluto, still defined as a planet at the time (Pluto's irregular orbit meant it was closer to the Sun than Neptune).[၂၈]
Template:Center Crossed orbit of Neptune, the furthest planet away from the Sun at the time, to become the first man-made object to depart the solar system.[၂၉]
Template:Center End of mission. Contact is maintained with spacecraft to record telemetry.[၃၀]
Template:Center Voyager 1 overtakes Pioneer 10 as the most distant man-made object from the Sun, at 69.419 AU. Voyager 1 is moving away from the Sun over 1 AU per year faster than Pioneer 10.[၃၀]
Template:Center Successful reception of telemetry. 39 minutes of clean data received from a distance of 79.83 AU[၃၁]
Template:Center Last successful reception of telemetry. 33 minutes of clean data received from a distance of 80.22 AU[၃၁]
Template:Center Final signal received from the spacecraft. Reception was very weak and subsequent signals were barely strong enough to detect.[၃၁]
Template:Center Unsuccessful attempt to contact spacecraft[၃၁]
Template:Center Pioneer 10 was projected to be 89.7 AU, traveling at a velocity of 12.51 kilometers/second (28,000 miles/hour), which is approximately 0.000041 the speed of light.
Template:Center Projections indicate that Pioneer 10 reached 100 AU. At this point, the spacecraft is approximately 271,000 AU from the nearest star, Proxima Centauri.[၃၂]
[၃]Template:Rp[၃၃][၃၄]

Current status[ပြင်​ဆင်​ရန်​]

Position of Pioneer 10 on the 8th of February 2012

On September 9, 2012, Pioneer 10 was Template:Convert/AU from the Earth and Template:Convert/AU from the Sun; and traveling at Template:Convert/km/s (relative to the Sun) and traveling outward at about 2.539 AU per year.[၃၅] Sunlight takes 14.79 hours to get to Pioneer 10. The brightness of the Sun from the spacecraft is magnitude -16.6.[၃၅] Pioneer 10 is heading in the direction of the constellation Taurus.[၃၅]

If left undisturbed, Pioneer 10 and its sister craft Pioneer 11 will join the Voyager spacecraft in leaving the solar system to wander the interstellar medium. The trajectory into the interstellar medium is expected to take it in the general direction of the star Aldebaran, currently located at a distance of about 68 light years. If Aldebaran had zero relative velocity, it would require more than 2 million years for the spacecraft to reach the star.[၂][၃၆]

A backup unit, Pioneer H, is currently on display in the "Milestones of Flight" exhibit at the National Air and Space Museum in Washington, D.C.[၃၇] Many elements of the mission proved to be critical in the planning of the Voyager program.Template:Sfn

See also[ပြင်​ဆင်​ရန်​]

References[ပြင်​ဆင်​ရန်​]

  1. ၁.၀ ၁.၁ ၁.၂ ၁.၃ Mark, Hans (August 1974). The Pioneer Jupiter Mission. SP-349/396 Pioneer Odyssey. NASA. Retrieved on 2011-07-06
  2. ၂.၀ ၂.၁ ၂.၂ ၂.၃ ၂.၄ ၂.၅ ၂.၆ Anderson, John D.; et al (April 2002). "Study of the anomalous acceleration of Pioneer 10 and 11". Physical Review D 65 (8). doi:10.1103/PhysRevD.65.082004. Bibcode2002PhRvD..65h2004A. 
  3. ၃.၀ ၃.၁ ၃.၂ ၃.၃ ၃.၄ Fimmel, R. O.; W. Swindell, and E. Burgess (1974). SP-349/396 PIONEER ODYSSEY. NASA-Ames Research Center. ISBN SP-349. Retrieved on 2011-01-09. 
  4. Template:Cite encyclopedia
  5. Weebau Spaceflight Encyclopedia (9 November 2010). Retrieved on 12 January 2012
  6. Template:Cite conference
  7. Template:Cite conference
  8. Smith, Edward J.. Magnetic Fields. NASA / National Space Science Data Center. Retrieved on 2011-02-19
  9. Quadrispherical Plasma Analyzer. NASA / National Space Science Data Center. Retrieved on 2011-02-19
  10. Charged Particle Instrument (CPI). NASA / National Space Science Data Center. Retrieved on 2011-02-19
  11. Cosmic-Ray Spectra. NASA / National Space Science Data Center. Retrieved on 2011-02-19
  12. Geiger Tube Telescope (GTT). NASA / National Space Science Data Center. Retrieved on 2011-02-19
  13. Jovian Trapped Radiation. NASA / National Space Science Data Center. Retrieved on 2011-02-19
  14. Meteoroid Detectors. NASA / National Space Science Data Center. Retrieved on 2011-02-19
  15. Asteroid/Meteoroid Astronomy. NASA / National Space Science Data Center. Retrieved on 2011-02-19
  16. Ultraviolet Photometry. NASA / National Space Science Data Center. Retrieved on 2011-02-19
  17. Imaging Photopolarimeter (IPP). NASA / National Space Science Data Center. Retrieved on 2011-02-19
  18. Infrared Radiometers. NASA / National Space Science Data Center. Retrieved on 2011-02-19
  19. Carl Sagan, Linda Salzman Sagan and Frank Drake (1972-02-25). "A Message from Earth". Science 175 (4024): 881–884. doi:10.1126/science.175.4024.881. PMID 17781060. Bibcode1972Sci...175..881S.  Paper on the background of the plaque. Pages available online: 1, 2, 3, 4
  20. NASA Glenn Pioneer Launch History. NASA/Glenn Research Center (March 7, 2003). Retrieved on 2011-06-13
  21. Staff (March 1, 1973). "Pioneer 10 beats the asteroid belt". New Scientist 57 (835). New Scientist Publications. 
  22. Britt, Robert Roy (October 18, 2004). The Problem with Gravity: New Mission Would Probe Strange Puzzle. Space.com. Retrieved on 2011-06-07။ “The discrepancy caused by the anomaly amounts to about 248,500 miles (400,000 kilometers), or roughly the distance between Earth and the Moon. That's how much farther the probes should have traveled in their 34 years, if our understanding of gravity is correct.”
  23. Pioneer Anomaly Solved!. The Planetary Society. Retrieved on 2012-04-20
  24. Support for the thermal origin of the Pioneer anomaly, Slava G. Turyshev et al, Physical Review Letters, accepted 11 April 2012, accessed 19 July 2012
  25. Phillips, Tony. "Seven billion miles and counting", High Energy Astrophysics Science Archive Research Center, NASA, May 3, 2001. Retrieved on 2011-06-07. 
  26. "This Month in History", Smithsonian magazine, June 2003.
  27. Lakdawalla, Emily (March 6, 2006). The final attempt to contact Pioneer 10. The Planetary Society. Retrieved on 2011-06-07
  28. Wilford, John Noble. "Pioneer 10 Pushes Beyond Goals, Into the Unknown", The New York Times, April 26, 1983. Retrieved on 13 June 2011. 
  29. Pioneer 10. Solar System Exploration. NASA. Retrieved on 13 June 2011
  30. ၃၀.၀ ၃၀.၁ Update on Pioneer 10. University of Iowa (February 17, 1998). Retrieved on 2011-01-09
  31. ၃၁.၀ ၃၁.၁ ၃၁.၂ ၃၁.၃ Update on Pioneer 10. University of Iowa (February 20, 2003). Retrieved on 2011-01-09
  32. Cosmic Distance Scales - The Nearest Star. NASA. Retrieved on 2011-06-07
  33. Pioneer 10 Mission Information. Retrieved on 2011-01-23
  34. Pioneer 10 Full Mission Timeline. Daniel Muller (2010). Retrieved on 2011-01-09
  35. ၃၅.၀ ၃၅.၁ ၃၅.၂ Peat, Chris (September 9, 2012). Spacecraft escaping the Solar System. Heavens-Above. Retrieved on September 9. 2012
  36. Peat, Chris. Spacecraft escaping the Solar System. Heavens Above. Retrieved on 2011-07-05
  37. Milestones of Flight. Smithsonian National Air and Space Museum. Retrieved on 2011-06-07

Bibliography[ပြင်​ဆင်​ရန်​]


External links[ပြင်​ဆင်​ရန်​]

Template:Pioneer program Template:Jupiter spacecraft Template:TRW