Things are finally looking up for the Voyager 1 interstellar spacecraft

[Admin]

Voyager 1's mission has been tumultuous lately, but scientists on the probe's flight team have turned optimistic about the situation.

Things are finally looking up for the Voyager 1 interstellar spacecraft : Read more

 

[Redderek]

Actually there are three Voyagers. The third is still at JPL. It is there to be used as a test bed for code check. Quite a nice piece of artwork, electronically. There are no processors since everything was made from discrete logic chips.

 

[Kastan]

Fun fact, there is no "up" in space.

 

[Helio]

Way to go Voyager 1! It is not too long for its 50th anniversary.

 

[billslugg]

Way to go Voyager 1! It is not too long for its 50th anniversary.

I remember when the Voyagers went up in 1977. They said they would enter interstellar space some day. I thought "Not in MY lifetime!!" Man, was my face red!

 

[Helio]

I remember when the Voyagers went up in 1977. They said they would enter interstellar space some day. I thought "Not in MY lifetime!!" Man, was my face red!

But has it? It’s past the heliopause, IIRC, but the Sun’s influence is about 1 lyr., where the Oort ends.

 

[24launch]

But has it? It’s past the heliopause, IIRC, but the Sun’s influence is about 1 lyr., where the Oort ends.

Mission scientists are indeed saying that they believe it is intersteller space based on the speed, direction and type of charged particles it's encountering.

Being an old fart the Voyagers have a special place in my heart. In the late 80's, particularly the summer of '89 my evenings were sitting outside, reading Cosmos and enjoying the clear Arizona skies with my little crappy 8" Coulter dobsonian. It was my first "real" telescope but was so cheap it didn't even have a spotting scope on it, so to aim it you had to lay on the ground from behind and eyeball down the tube like you were aiming a cannon. Then of course LOTS of panning back and forth when back at the eyepiece. But some of the things I saw for the first time for myself, like Saturn, were breathtaking for a THEN young enthusiast.

Aug '89 was also when Voyager 2 flew by Neptune, which was and still is my favorite planet. I remember staying up all night watching the live JPL broadcast on PBS as they were waiting for the downlink of that first black & white image that was still the best we'd ever seen of that far away ice giant. Good times!

 

[billslugg]

But has it? It’s past the heliopause, IIRC, but the Sun’s influence is about 1 lyr., where the Oort ends.

Every atom in the universe influences every other atom. The Sun's influence is predominant up until half way to the nearest star. Once past that point the probe would be in another star system. I always took the heliopause to be where interstellar space started.

 

[Helio]

Every atom in the universe influences every other atom. The Sun's influence is predominant up until half way to the nearest star. Once past that point the probe would be in another star system. I always took the heliopause to be where interstellar space started.

I would guess that wherever the Oort objects are no longer found might be the appropriate "limit" to our solar system. Otherwise, if we claim something inside the Oort cloud to be the limit, then why aren't the outer Oort objects part of the "system". On the other extreme, if we find no Oort objects, say after 1 lyr., then why wouldn't that be the limit to the "system"?

NASA, from one page I saw, suggests this limit is between 10,000 AU and 100,000 AU. Perhaps not knowing just how close other stars were to us in the distant past limits what this limit is, assuming existing objects is the proper way to determine the size of a "system".

 

[ronih]

What I find even more amazing is that they can find and successfully receive the signal from the Voyager probes. I think the transmitters are only like 20 watts and the fact that NASA/JPL can pick out a signal that weak from 12-15 billion miles away through all the background noise is astounding.

 

[Classical Motion]

What's the bit rate now?

 

[Classical Motion]

Voyager 1 is going 35 degrees N and Voyager 2 is 43 degrees S of Sol's velocity. When will we notice a change in velocity and distance of these two craft, due to Sol's velocity?

 

[Pogo]

Both definitions of the Solar System could be valid. A spacecraft on a transfer orbit beyond the Earth-Moon system will experience interplanetary medium once it gets sufficiently beyond the outer Van Allen belt, but, gravitationally, it will have left the system when the gravitation the the Sun exceeds that of Earth-Moon. Voyager I is in the intergalactic medium, but leaves the gravitational system when gravity of the next star in that direction exceeds that of the Sun. That’ll be some years yet. And that’s when you will see the trajectory change.

I saw on a site that V I transmits data at 320 Hz, but that’s only for a few seconds, but then it takes about two days for it to be received, transmit a reply, and be received by the craft, because of c.
Yeah, truly amazing that we can communicate at that distance, but, the plutonium power source will fall below minimum needed before it actually gets out of range.

 

[Torbjorn Larsson]

I'm happy for Voyager! And the rest of us, despite hearing that all the previous data feeds (or the instruments) are still not up to speed.

No less because Daisy Dobrijevic managed to write such a poignant, detailed and personal writeup. A small nitpick would be allowing a possible translation of digital circuit general use of binary logic of "the neatly organized and data-rich 0's and 1's" as a "classic computer language". [There has always been third state realizations such as floating gates added to the transistors on/off states, and with EEPROM gates you can have many more distinguishable memory states. But they are all translated from, and back to, "binary" for general use.]

A promising context is that the happenstance extended Voyager missions has prompted questions that can only be answered by future planned missions further out.

By performing a slingshot maneuver in the vicinity of the sun, just ~2-5 solar radii distant from the sun, solar sails can propel light-weight cubesat class spacecraft to near-relativistic speeds, >0.1% of the speed of light (>300 km/s or >60AU/year characteristic velocities).

We will explore the utility of extreme solar sailing for two breakthrough mission concepts: Fast Transit Interstellar Probe, which aims to send a probe to 500 AU in 10 years, ...

https://www.nasa.gov/general/extreme-solar-sailing-for-breakthrough-space-exploration/

 

[Torbjorn Larsson]

I would guess that wherever the Oort objects are no longer found might be the appropriate "limit" to our solar system. Otherwise, if we claim something inside the Oort cloud to be the limit, then why aren't the outer Oort objects part of the "system". On the other extreme, if we find no Oort objects, say after 1 lyr., then why wouldn't that be the limit to the "system"?

NASA, from one page I saw, suggests this limit is between 10,000 AU and 100,000 AU. Perhaps not knowing just how close other stars were to us in the distant past limits what this limit is, assuming existing objects is the proper way to determine the size of a "system".

There will always be boundary issues akin to "where does the tree branch start, at its root inside the tree stem or as a cut along the stem or as a cut perpendicular at the stem" et cetera. US uses a lenient "space" definition to allow X15 test pilots to have reached it, others use a harsh definition of the Karman line (but satellites can travel below it for more than one orbit). Earth atmosphere stops at space or envelops Moon (hydrogen escape). Et cetera.

Mostly, as comments before me alludes to, we need to keep several useful descriptions in mind despite that they overlap.

Think of the heliopause as the boundary where Voyagers can start to probe the interstellar medium. The debris cloud can along those lines be thought of excited "particles" (roughly analogous to boiling water) - though the heliosphere is mostly magnetism and gas phenomena, not a gravity and debris phenomena. The Oort cloud doesn't quite reach the next system now, but in the Sun birth cluster where it was once established it shared material with other stars. Current estimates are 10 % of the cloud objects are foreign, but spectroscopy of the first identified interstellar objects passing through likely means the numbers have to be revised (some objects are indistinguishable from Sun's material).

Passing stars doesn't affect the system much. Recent models says about 10 % of climate affecting Earth orbit variation is from galactic tides of nearby passing objects. They may pass closer than the Oort cloud smallest radius estimates. Here is a description of some work on the question:

Bailer-Jones identifies the key candidates in this paper, assuming an Oort Cloud that extends to about 0.5 parsecs (1.6 light years), but he notes that a star passing even as close as several parsecs could produce significant cometary disruptions if the star were massive and slow enough. The author worked with 50,000 stars from the Hipparcos astrometric catalog in hopes of fine-tuning earlier studies of passing stars, but he notes that the search can’t be considered complete because radial velocities are not available for all stars and many are fainter than the Hipparcos work could detect. Further analysis will be needed using upcoming Gaia data.

But studying stars within a few tens of light years from the Solar System, Bailer-Jones finds forty that at some point were or will be within 6.4 light years of the Sun — the timeframe here extends from 20 million years in the past to 20 million years in the future. Fourteen stars, in fact, come within 3 light years of the Sun, with the closest encounter being with HIP 85605, which is currently about 16 light years away in the constellation of Hercules. The paper cites “…a 90% probability of [the star] coming between 0.04 and 0.20 pc” somewhere between 240,000 and 470,000 years from now, but Bailer Jones notes that this encounter has to be treated with caution because the astrometry may be incorrect. Future Gaia data should resolve this.

If HIP 85605 were to close to 0.04 parsecs of the Sun, it would be .13 light years out, or roughly 8200 AU, a close pass indeed. But one thing to keep in mind: Oort Cloud perturbation is not an unusual phenomenon, and the situation we are dealing with today is partially the result of encounters with stars that have occurred in the past.

https://www.centauri-dreams.org/2015/01/02/stars-passing-close-to-the-sun/

 

[DrRaviSharma]

Hello thread related Colleagues
Extremely exciting comments! Appreciating the opportunity to absorb from knowledge of commentators.
A few more:

• Oort clouds are not that well shaped nor necessarily heliocentric except in long ellipse sense
• Statistics on cometlike objects apparently source being Oort Clouds (or even Kuiper belts), as to how many turned out to be actually not from them but captured due to perturbations, ion/ charge influenced and gravitational effects on objects from Oort clouds of other moving stars
• Are asteroid belt objects and comets not fuzzy or similarly comet like (>large AUs say 1000) objects entering or leaving solar influence at very large distances not less determinate?

As I plan to publish in a short article, next set of Voyagers ought to be multiple nuclear fission (and ASAP Fusion) robotic missions assembled away from cis-lunar space with as discussed by you assisted by solar gravitation sling-shots to provide 2 generations downstream the necessary answers to Qs like we are asking and some answers that we are getting from NASA and others foresightedness and pioneers!
Sparse-ness of interstellar grains and massive matter in interstellar space is indicated by one statistically fortunate trajectory of pioneer or voyager without collision!

Regards.
Ravi
(Dr. Ravi Sharma, Ph.D. USA)
NASA Apollo Achievement Award
ISRO Distinguished Service Awards
Former MTS NASA HQ MSEB Apollo
Former Scientific Secretary ISRO HQ
Ontolog Board of Trustees
Particle and Space Physics
Senior Enterprise Architect
SAE Fuel Cell Tech Committee voting member for 20 years.
http://www.linkedin.com/in/drravisharma

 

[Helio]

There will always be boundary issues akin to "where does the tree branch start, at its root inside the tree stem or as a cut along the stem or as a cut perpendicular at the stem" et cetera. US uses a lenient "space" definition to allow X15 test pilots to have reached it, others use a harsh definition of the Karman line (but satellites can travel below it for more than one orbit). Earth atmosphere stops at space or envelops Moon (hydrogen escape). Et cetera.

Yes, IIRC, the Karman line is 100 km and the space program uses 80 km. The Karman line is 25% higher.

Voyager 1 is currently 162.8 AU from Earth, and it is in or through the heliopause. But the distance beyond the "system" may be as much as 100,000 AU. So the difference is too extreme to not justify better labeling.

Passing stars doesn't affect the system much. Recent models says about 10 % of climate affecting Earth orbit variation is from galactic tides of nearby passing objects. They may pass closer than the Oort cloud smallest radius estimates. Here is a description of some work on the question:

https://www.centauri-dreams.org/2015/01/02/stars-passing-close-to-the-sun/

Thanks. That's interesting. I backtracked Scholz and calculated it passed just under 1 lyr. from the Sun 70k years ago. So it has happened even in the not too distant past. It may be a great thing if such passages have little effect on them.

 

[newtons_laws]

And Voyager I is now back doing Science. sending back data from its onboard instruments about plasma waves, magnetic fields and particles: https://abcnews.go.com/Technology/w...tant-spacecraft-earth-science-after-111130720