Voyager 1 Beyond Solar Wind

healeyb noted that Voyager 1 has now reached a distance from the sun where it is no longer able to detect solar wind. Launched in 1977 to get up close and personal with our solar system's gas giants, scientists estimate that in another 4 years it will cross the heliosphere.

Comments

I feel a kinship with voyager

[arcite]

Since it is almost the same age as me, I feel a kinship with the little guy. It's amazing that it's still sending back readings after all theses years and millions of miles travelled in the deep dark infinite space. Onward to interstellar space! Godspeed!

NASA Craftsmanship

[Goboxer]

With how well NASA's gear works long after their mission is complete perhaps they should start selling toys and cars to fill in all those budget holes that they have.

Re:Data transfers

[john83]

From here,

The total cost of the Voyager mission from May 1972 through the Neptune encounter (including launch vehicles, radioactive power source (RTGs), and DSN tracking support) is 865 million dollars.

and

A total of five trillion bits of scientific data had been returned to Earth by both Voyager spacecraft at the completion of the Neptune encounter.

That's $0.001384 per bit. There are 1120 bits in an SMS message. That's about $1.55 per SMS. Not exactly cheap, but then Vodafone don't have coverage beyond Pluto.

Why cant we have more science like this?

[Lumpy]

Voyager probes are frigging HUGE. why cant we launch the same thing twice, but have them assemble in orbit and give it a chemical kick in the ass to get the slingshotting down and then when it get's it's last slingshot around juipeter kick in the Ion engines to do a long hard burn for a few years to get the thing really hauling ass.

I'll bet with current tech we can get past Voyager 1 within 10 years AND have better instruments, a stronger transmitter, far more sensitive receiver, etc.... Seriously. NASA could do this right now and we might see a flyby of another star within a 200 year window.

Re:Why cant we have more science like this?

[Lumpy]

" Voyager has taken since 1977 to get where it is and is currently hitting 14km/s. At those speeds, dusts rips you apart let alone anything else (it's 50400 km/h or 31317 mph). It takes YEARS to accelerate to that speed even with a constant acceleration from a nuclear powered engine that has had to work, unattended, since before I was born."

Voyager has NO Thrust engines only attitude control. It's last acceleration was during a slingshot past the gas giants. It has had ZERO acceleration since 1979.

Also Voyager 1 and 2 have no problem with this rip me apart dust you seem to think is all over the place out there.

as for your claims of impossibility... So then Voyager 1,2, Viking, the Moon landings all were faked then? Because I'm asking for no more than doing what we did in the 70's but with current technology. It is very possible.

Proxima Centauri is 4.2 light years out. an ion engine being able to thrust for 20 years with a set of Gridded Electrostatic ion thrusters achieve 100 kNs/k and some have had 210 kNs/k but not tested in continuous operation for 3 years like the older ones. Designing a craft to have 20 years worth of fuel and Nuclear power is not hard at all we did it in the 70's. and that kind of acceleration would get the craft to a fraction of light speed. Even a 1KW transmitter can send back telemetry to earth at a 1 light year distance if you reduce the data rate and still have fuel to keep the antenna pointed home.

Granted giving it commands will be difficult, but we can make it smart so it can operate on it's own or with limited command needs.

All of it is doable because we already did the hard parts of it several times already.

Solar wind decline, not beyond solar wind

[chebucto]

I am not an astrophysicist, so I don't understand the subtelties of this, but it should be noted that NASA press release says the probe has measured a solar wind decline, not that the probe is beyond the solar wind. Specifically, it says the solar wind has 'no outward motion'. The probe's environment is still dominated by the solar wind because it is still in the heliosphere, or, as NASA says, 'Crossing into interstellar space would mean a sudden drop in the density of hot particles and an increase in the density of cold particles.'

http://www.nasa.gov/mission_pages/voyager/voyager20101213.html

Now hurtling toward interstellar space some 17.4 billion kilometers (10.8 billion miles) from the sun, Voyager 1 has crossed into an area where the velocity of the hot ionized gas, or plasma, emanating directly outward from the sun has slowed to zero. Scientists suspect the solar wind has been turned sideways by the pressure from the interstellar wind in the region between stars.

...

Scientists believe Voyager 1 has not crossed the heliosheath into interstellar space. Crossing into interstellar space would mean a sudden drop in the density of hot particles and an increase in the density of cold particles. Scientists are putting the data into their models of the heliosphere's structure and should be able to better estimate when Voyager 1 will reach interstellar space. Researchers currently estimate Voyager 1 will cross that frontier in about four years.

Re:17.5 billion kilometers

[crunchygranola]

True, Voyager 1 has only travelled a short way between stars within our galaxy -- but here is a cool fact (I think).The Milky Way Galaxy is moving relative to the rest of the Universe (as defined by the Cosmic Microwave Background frame of reference) at 279 ± 68 km/sec, just under 0.1% the speed of light. This is the speed with which we are moving through the Universe. Thus if you live to be 80 years old (a typical lifespan today) you will die in a region of the Universe 0.074 light years from where you were born, and the first pyramids were built in Egypt in a region of the Universe more distant than Alpha Centauri.

CPU - lowly RCA 1802

[Sooner Boomer]

Wow, just wow! Not even a 6502. The Voyagers used a trio of 1802s clocked at 6.4MHz. Just goes to show what you can do with a specific bit of hardware and tight code.

Re:An amazing achievement

[Chris Burke]

If we had the collective courage [read - no enviro-wackos] to use RTGs [wikipedia.org] on our Mars probes, we wouldn't have lost Spirit to freezing temperatures brought on by low power from the solar cells.

LOL, that's why you think Spirit and Opportunity didn't use them? Enviro-wackos?

The real reason is simply optimizing for the mission profile. The MERs were relatively small devices with very tight mass budgets, and an RTG of sufficient power would have been too heavy compared to the solar panel/battery combo they went with instead. It was an engineering trade-off. They did, by the way, use RHUs to heat components but this was not sufficient to stave off freezing by itself.

The Mars Science Laboratory is going to use an RTG. It is a much larger rover, with power demands beyond what solar panels could provide, and with a more generous amount of mass to dedicate to the power system.

We used 'em on quite a few spacecraft [wikipedia.org] - why they aren't used more often for solar power-limited missions escapes me.

Yeah, which I would think would have suggested that maybe enviro-wacko objection to the concept of RTGs had nothing to do with it. This is a lobby with surprisingly less power than you might think. :)