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78

New Horizons will never overtake Voyager 1. Although New Horizons is currently faster than any other man-made object, it won't be by the time it reaches the outer corners of the solar system. From the John Hopkins University/Applied Physics Laboratory New Horizons page: Though New Horizons will also reach 100 AU, it will never pass Voyager 1, because ...


72

Voyager 1 was the first to reach Jupiter and the first to reach Saturn, as it was launched on a "shorter and faster trajectory" (Wikipedia, NASA). So the numbering was chosen to reflect the order of the main part of the mission, not the launches. I have not found any sources explicitly stating that as the reason, but the arrivals at Jupiter and Saturn ...


59

No, not even slightly. Neither Voyager has much fuel left; in fact, they don't have much fuel even for changing their attitude (the way they point), which is orders of magnitude less fuel than for making major course changes, and the course change necessary to return to Earth is so large it would never have been possible in any case: both probes used gravity ...


49

The trajectory was not only "unhindered" - it was enhanced! Knowing mass of the planet you can calculate very precisely how the trajectory of a probe flying by will be affected. You modify the trajectory on arrival in such a way, that the departure trajectory will be exactly as desired. And due to some rather unintuitive physics caveats, you can make it so ...


46

Here's a nice graph of Voyager 2's speed, and the difference made by the gravitational assists: You can see that the probe slowed down between assists. New Horizons would follow a similar graph, but with fewer assists its speed will end up below Voyager 2's, as @gerrit said.


46

why weren't they completely attracted by their gravitational field? How much a trajectory is changed, depends on 3 factors: the mass of the planet, the speed of the spacecraft, the distance between spacecraft and planet Voyager's speed and distance were chosen to make sure Voyager wouldn't enter orbit around the planet. Voyager's speed before approaching ...


43

The mission was to fly by the outer planets. Once it got to Neptune that mission was complete. From Wikipedia: Because this was the last planet of the Solar System that Voyager 2 could visit, the Chief Project Scientist, his staff members, and the flight controllers decided to also perform a close fly-by of Triton, the larger of Neptune's two originally ...


38

Communication system: The radio communication system of Voyager 1 was designed to be used up to and beyond the limits of the Solar System during the extremely long flight of this space probe. The communication system includes a 3.7 meter diameter parabolic dish high-gain antenna to send and receive radio waves via the three Deep Space Network ...


37

From the Voyager FAQ Question: Can the Voyager imaging cameras be turned back on? Answer: It is possible for the cameras to be turned on, but it is not a priority for Voyager's Interstellar Mission. After Voyager 1 took its last image (the "Solar System Family Portrait" in 1990), the cameras were turned off to save power and memory for the ...


36

Interplanetary communication is mainly dependent on signal strength (for transmission) and antenna size (for reception). The Pioneers use a 9-foot antenna and an 8-watt transmitter. The Voyagers use a 12-foot antenna and a 20-watt transmitter, allowing a substantially stronger signal to be received on Earth.


35

They wanted a close flyby of Triton. Triton's orbit is at a large angle to the ecliptic plane, and Triton was below Neptune at the time of Voyager's flyby, so they needed a course change that pointed "down" from Neptune. From the Voyager Neptune travel guide (large PDF), page 118-119 of the PDF (page number 107-108 indicated on the page): However, ...


33

In 2015, the last original Voyager engineer still on the project, retired. NASA specified that his replacement would have to know FORTRAN. The software was updated regularly after launch: The last true software overhaul was in 1990, after the 1989 Neptune encounter and at the beginning of the interstellar mission. "The flight software was basically ...


31

Voyagers are still active, and albeit they don't have the power required to run all the scientific equipment onboard and some of it stopped working by now, they still transmit telemetry data streams towards the Earth that is picked up by NASA JPL's 70-meter antenna at Goldstone, California, part of the Deep Space Network. Quoting from Wikipedia on Voyager ...


29

But if some space debris comes on its way or any of the extra planetary objects comes on its way then how it changes its path? Not only won't Voyager 2 change it's path, it can't change it's path. Suppose you drop your cellphone from the top of a tall building. Your cellphone is going to fall and hit the ground, hard. Your cellphone has no sensors to ...


28

No, it's not feasible. The fundamental problems that prevent this are: The Pioneers do not have enough power to operate the transmitter, due to corrosion of the thermocouples The Voyagers and Pioneers, even at full power, use very low power transmissions The Pioneers would need to be able to receive and obey instructions to aim for a Voyager The craft are ...


27

You are correct that Voyager did not change from above escape velocity to below escape velocity shortly after launch. The plot is misleading in that it is just not very accurate right there at 1 AU. The plot lines are kind of thick and a smidge off. Now that I look at it more closely, the escape velocity line in that plot is wrong in other places as well. ...


27

In addition to a better transmitter, the Voyagers have better power reserves: their RTGs supplied 470 W at launch, while the Pioneer RTGs supplied 160 W at launch. So the Voyager RTGs will take much longer to decay to a point where they can't power the spacecraft. NASA seems to think RTG decay is the primary reason we can't receive Pioneer 10 any more: ...


27

Most likely no. Voyager downlink communication (via its radio link to NASA's Deep Space Network (DSN) is not continuous. You can check the contact schedule at this Voyager site. If everything looks fine during one DSN contact period, and then at the next contact period there's no signal at all, there are myriads of possible causes, ranging from failure of ...


26

Space is almost completely empty. The voyager probes are exceedingly unlikely to collide with anything (as demonstrated here: What is the possibility of Voyager 1/2 colliding with matter (Asteroids or planetoids) present in space?) larger than a mote of dust. If they did collide with anything at 15 km/s, then it slowing them down would be the least of their ...


25

They did not ! This is the trajectory of Voyager 1 at Jupiter. credits wikipedia


25

Why the Pioneers didn't last as long: The Pioneers were a low-budget mission just to test if flying to the outer planets was feasible They used a smaller radio transmitter (8 W vs. 23 W) and antenna (2.7 vs 3.6 m diameter) so their signals are weaker The Pioneers used a smaller, earlier design Radioisotope thermoelectric generator as their power source (...


25

Physical First and foremost, the physical reason is that objects accelerate as they approach massive bodies and decelerate as they recede: Parker Solar Probe achieves its peak orbital speed (almost 200 km/s eventually) at its closest approaches to the Sun - as it falls inwards towards the Sun on each orbit it speeds up then slows down again on the way back ...


24

The initial plan was to visit all of the outer planets: The Planetary Grand Tour was to send several pairs of probes to fly by all the outer planets (and Pluto) along various trajectories, including Jupiter-Saturn-Pluto and Jupiter-Uranus-Neptune. Limited funding ended the Grand Tour program, but elements were incorporated into the Voyager Program, which ...


23

No, absolutely none. Even assuming Pioneer 11's transceiver still works, and there's no reason to believe that, that image you attach of distances between the three probes isn't showing it proportionally correct, since it's merely an approximate slice of euclidean space and is not axially aligned with anything to correctly appreciate distances involved. So ...


23

These were the last photos Voyager 1 took, on February 14, 1990: This became known as the "Pale Blue Dot" photo. And the Solar System Family Portrait: Voyager 1 had traveled 6 billion km at that time. After these images were taken, the camera was shut down as @Pearson says. Voyager took 60 photos. This shows all of them: On some of the photos, you can ...


23

Yes, the Earth can send Voyager 1 a message as easily as we can receive a message. There are a few differences between the uplink and the downlink paths. We cannot upgrade the radio on Voyager 1 to newer equipment (but an upgrade to the Earth station is equally beneficial), The gain of the antennas on the spacecraft and on Earth are constant, and the free ...


23

The tape recorder on Voyager 1 is still in use: Science data are returned to earth in real time at 160 bps. Real time data capture uses 34 meter Deep Space Network (DSN) resources (see below) with the project goal to acquire at least 16 hours per day of real time data per spacecraft. This goal is not always achieved due to the competition for DSN ...


22

New Horizons has examined Pluto on 14 July 2015 and Ultima Thule on 1 January 2019. It may continue to explore a third Kuiper Belt object, but it's not aiming to measure the interstellar medium, let alone nearby stars; it's too slow for that. It didn't go into orbit in the Pluto-Charon system; there's no atmosphere thick enough for aerobraking, and it ...


22

Would the engineer team here on Earth detect it? How? There are two issues here. Suppose Voyager 2 (Voyager 1 is moving faster and is further away, so the effect will be lesser on Voyager 1 than on Voyager 2) made a ridiculously close flyby of an object with a similar size and mass of Neptune. Such a flyby would result in a delta-V of about 8.2 km/sec. ...


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