Voyager 1 spacecraft phones home with transmitter that hasn't been used since 1981

[Admin]

Following recent communication issues, NASA's Voyager 1 spacecraft resorted to a backup radio transmitter that has been inactive since 1981.

Voyager 1 spacecraft phones home with transmitter that hasn't been used since 1981 : Read more

 

[Joexo]

Can someone explain me how is it possible that we can send a message from here and Voyager will receive it even if 25 billion km from us?

There are no interferences in space? I would think that if nothing else at least there should be the chance that planets make some kind of "shadow"?

I suppose the Voyager is on a different plane than the planet so there's just vacuum?

 

[George²]

1. Can someone explain me how is it possible that we can send a message from here and Voyager will receive it even if 25 billion km from us?

2. There are no interferences in space? I would think that if nothing else at least there should be the chance that planets make some kind of "shadow"?

3. I suppose the Voyager is on a different plane than the planet so there's just vacuum?

1. Answer Much more energy per received and transmitted bit of information. Data is digital not analogue.
2. Perhaps you imagine the planets very large, like some diagram of the solar system that shows the planets on a scale that in no way corresponds to the real thing. But even the star Sun is tiny compared to billions and tens of billions of miles, and the planets are vastly smaller. Yes, the planets are an obstacle, but when distance now is so big it's so minor* and besides they move and they don't cover their entire orbits in the plane (ecliptic) constantly.

3.Yes, the trajectory of the Voyagers was slightly above and below eclipse when travelling in solar system between planets with reason to avoid collision with dust and asteroids. After end of planetary part of Voyager 1 mission it's trajectory was set to big angle above ecliptic. Video.

*Of course, when Voyager was still traveling between the planets and was close to and behind them relative to Earth, the influence of the large planets and their magnetospheres was significant.

 

[RBruce]

Does planetary gravity affect signal transmission direction and speed?

 

[Meteoric Marmot]

Does planetary gravity affect signal transmission direction and speed?

All gravity wells warp spacetime, but planets are so small (relatively speaking) that I assume that their effect is minor to negligible.

The "speed of transmission" is an inexact term. The signal itself travels at the speed of light (because it is electromagnetic radiation just as light is) and it is not affected by gravity, only by changes in the medium it is traversing.

The speed of data transmission is a different animal and depends on a variety of factors -- predominantly on the technology used. I can't think of anything that gravity could affect, but I could be wrong.

 

[BrianR]

What happened to voyager 2? Is that still functioning?

 

[billslugg]

EM waves respond to gravity. The Sun's gravity will bend the light of a star behind it.
Gravity warps spacetime. Everything follows spacetime, whether massive or not.

 

[RBruce]

All gravity wells warp spacetime, but planets are so small (relatively speaking) that I assume that their effect is minor to negligible.

The "speed of transmission" is an inexact term. The signal itself travels at the speed of light (because it is electromagnetic radiation just as light is) and it is not affected by gravity, only by changes in the medium it is traversing.

The speed of data transmission is a different animal and depends on a variety of factors -- predominantly on the technology used. I can't think of anything that gravity could affect, but I could be wrong.

Let me restate. Assume signal travels at the speed of light. Does gravity affect the distance travelled which would lengthen the time from the point-of-view of someone on Earth. Rough calculations shows a signals takes 22hours to be received. A lot can alter the signal's course. Is there a time synchronization code between Voyager and receiver to calculate distance? Is there a second distance measurement to compare the receiving times?

 

[bolide]

EM waves respond to gravity. The Sun's gravity will bend the light of a star behind it.
Gravity warps spacetime. Everything follows spacetime, whether massive or not.

Not an issue in the present case. There's no gravitational force between us & the satellite that would have a meaningful effect on signals sent or received.

 

[billslugg]

The gravitational field of the Sun will affect EM waves slightly. The effect on the outgoing signal is exactly balanced by the effect on the incoming signal.

 

[Torbjorn Larsson]

It 's both heroic and nail biting worthy, but every little holdup interferes with and cuts down on the remaining science.

Voyager 1's extended mission is expected to continue to return scientific data until at least 2025, with a maximum lifespan of until 2030.

https://en.wikipedia.org/wiki/Voyager_1

What happened to voyager 2? Is that still functioning?

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.[4]

The probe entered the interstellar medium on November 5, 2018, at a distance of 119.7 AU (11.1 billion mi; 17.9 billion km) from the Sun[5] and moving at a velocity of 15.341 km/s (34,320 mph)[4] 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.[6][7][8][9] Voyager 2 has begun to provide the first direct measurements of the density and temperature of the interstellar plasma.

https://en.wikipedia.org/wiki/Voyager_2

EM waves respond to gravity. The Sun's gravity will bend the light of a star behind it.
Gravity warps spacetime. Everything follows spacetime, whether massive or not.

The non-reciprocal gravitational time dilation differences in climbing out of Sun's gravity well at large distances doesn't seem to interfere with the signal decoding timing, and for radial signals the space curvature lensing will be insignificant.

Radio astronomy can currently look back to the early universe, whether for strong radio bursts or for weak gas cloud emissions. (Admittedly in the latter case with the cheat of precisely strong gravitational lensing amplification of 30 times with the help of a foreground object. We need at least 100 - 1000 times better radio telescopes!).

This 'fast radio burst' (FRB) is the most distant ever detected. Its source was pinned down by the European Southern Observatory’s (ESO) Very Large Telescope (VLT) in a galaxy so far away that its light took eight billion years to reach us. The FRB is also one of the most energetic ever observed; in a tiny fraction of a second it released the equivalent of our Sun’s total emission over 30 years.

https://www.eso.org/public/news/eso2317/

Using GMRT data, Arnab Chakraborty, postdoctoral researcher at the Department of Physics and Trottier Space Institute of McGill University, and Nirupam Roy, Associate Professor, Department of Physics, IISc have detected a radio signal from atomic hydrogen in a distant galaxy at redshift z=1.29.

"Due to the immense distance to the galaxy, the 21 cm emission line had redshifted to 48 cm by the time the signal traveled from the source to the telescope," says Chakraborty. The signal detected by the team was emitted from this galaxy when the universe was only 4.9 billion years old; in other words, the look-back time for this source is 8.8 billion years.

This detection was made possible by a phenomenon called gravitational lensing, in which the light emitted by the source is bent due to the presence of another massive body, such as an early type elliptical galaxy, between the target galaxy and the observer, effectively resulting in the "magnification" of the signal. "In this specific case, the magnification of the signal was about a factor of 30, allowing us to see through the high redshift universe," explains Roy.

https://phys.org/news/2023-01-record-breaking-radio-atomic-hydrogen-extremely.html

 

[dfwelch]

1. Answer Much more energy per received and transmitted bit of information. Data is digital not analogue.
2. Perhaps you imagine the planets very large, like some diagram of the solar system that shows the planets on a scale that in no way corresponds to the real thing. But even the star Sun is tiny compared to billions and tens of billions of miles, and the planets are vastly smaller. Yes, the planets are an obstacle, but when distance now is so big it's so minor* and besides they move and they don't cover their entire orbits in the plane (ecliptic) constantly.

3.Yes, the trajectory of the Voyagers was slightly above and below eclipse when travelling in solar system between planets with reason to avoid collision with dust and asteroids. After end of planetary part of Voyager 1 mission it's trajectory was set to big angle above ecliptic. Video.

*Of course, when Voyager was still traveling between the planets and was close to and behind them relative to Earth, the influence of the large planets and their magnetospheres was significant.

As an example of #2, few people realize the following statistic. You can fit the other 7 planets between the earth and the moon, and still have nearly 5,000 miles to spare. Objects in our solar system are extremely small compared to space