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47-year-old Voyager 1 fired up thrusters it hasn't used in decades

cnn.com

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Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#61

Post by secondcoming »

Rinzler89 wrote: post #31
quesera wrote: post #25

Earlier quoted context omitted.

> A radio signal takes more than 22 hours to reach Voyager 1 Voyager has a 23 watt radio and a 14 foot parabolic dish antenna, pointed directly at Earth which is presently 15 billion miles away. The corresponding earth ground station has a 100 foot dish and transmits at thousands of watts. It's astonishing to me that Voyager knows where Earth is at all. I imagine it uses Sol as a reference? Or maybe the high powered…

>It's astonishing to me that Voyager knows where Earth is at all It's not that astonishing when you realize astral navigation is what sailors hundreds of years ago did to navigate the seas. Just look at the stars with a sextant and with some basic trigonometry you'll know where you are exactly. The Apollo space crew had to do that by hand and eyes using a sextant too when the astral navigation computer failed.

Does voyager have optical sensors that detect planets?

Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#63

Post by perihelions »

ucyo wrote: post #59

Does anyone know what the reference points are for the rotation manoeuvres? The text does not provide any information on how the probe knows that it is off. It needs some kind of reference, no?

A star tracker is one of its reference points (of absolute orientation). There's also a sun sensor with a similar function. I don't know if Voyagers have others.

- "In flight, the device found and locked on to the star Canopus, providing a reference for guidance and navigation."

https://airandspace.si.edu/collection-objects/star-tracker-a... ("Star Tracker and Hood Assembly Support Equipment, Voyager Spacecraft")

https://airandspace.si.edu/collection-objects/sun-sensor-and... ("Sun Sensor and Hood Assembly Support Equipment, Voyager Spacecraft")

edit: In more detail,

https://space.stackexchange.com/questions/43803/how-did-the-...

Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#64

Post by prettyStandard »

dTal wrote: post #53
piokoch wrote: post #24

You can agree with me or not, but Voyager 1/2 is a top technological achievement of the humankind. A piece of hardware so good that it survived working correctly 47 years in a hostile environment, driven by a computer with the power of modern car key. Amazing.

>driven by a computer with the power of modern car key I appreciate the sentiment, but perhaps it is the car key which is impressive here...

As I'm on my 3rd car key for a car I've had about 8 years. Nevermind I disassemble the key and clean the button and battery terminals.

Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#65

Post by jmclnx »

This is great, I love following the Voyagers.

>When Voyager 1 lifted off to space on September 5, 1977, no one expected that the probe would still be operating today.

This is kind of an odd statement :) When launched, I remember brief news broadcasts and articles in the local newspaper stating the engineers added abilities that were not approved hoping for a much longer life time. It never stated if they got in trouble. But lasting this long is quite an achievement.

Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#66

Post by fourgreen »

dcl wrote: post #37
Rinzler89 wrote: post #31

Earlier quoted context omitted.

>It's astonishing to me that Voyager knows where Earth is at all It's not that astonishing when you realize astral navigation is what sailors hundreds of years ago did to navigate the seas. Just look at the stars with a sextant and with some basic trigonometry you'll know where you are exactly. The Apollo space crew had to do that by hand and eyes using a sextant too when the astral navigation computer failed.

Knowing your longitude is very difficult without a clock... Can't do it with just stars iirc.

You can determine your longitude without a clock, but achieving precision with this method is challenging. First, you need to observe the Moon's position relative to fixed stars, which gives you the UTC time. Then, observe the Sun's position relative to the horizon to determine the local time. By comparing the two, you can calculate your longitude.

Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#67

Post by Brian_K_White »

bigiain wrote: post #10
yashg wrote: post #6

A radio signal takes more than 22 hours to reach Voyager 1. And it would take the same to get a response back. Incredible. And imagine the patience needed to send commands and wait for the outcome on the part of the engineering team. You can't afford to send a wrong command and have the luxury of undo. Also, I wonder how many generations of engineers must have worked on the project by now.

I suspect most people who've ever been responsible for colo-ed unix-ish servers have learned to do something like: > ufw reset | at now +5 minutes When doing "dangerous" things like updating firewall rules. I wonder if they have a way to send commands saying something like: Switch to thruster set 1, wriggle the antenna aim away and back to earth, wait 46 hours, if you do not receive "all clear" from earth switch back…

No I just always have a serial console and a power switch which are not affected by anything I can do on that box.

Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#68

Post by monkeyfun »

fourgreen wrote: post #66
dcl wrote: post #37

Earlier quoted context omitted.

Knowing your longitude is very difficult without a clock... Can't do it with just stars iirc.

You can determine your longitude without a clock, but achieving precision with this method is challenging. First, you need to observe the Moon's position relative to fixed stars, which gives you the UTC time. Then, observe the Sun's position relative to the horizon to determine the local time. By comparing the two, you can calculate your longitude.

How are you going to usefully use this information if you wouldn't have an obvious way to know precisely how long it's been between whenever you lost track of the moon and stars and whenever the sun is clearly visible over the horizon?

Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#69

Post by LinuxBender »

piokoch wrote: post #24

You can agree with me or not, but Voyager 1/2 is a top technological achievement of the humankind. A piece of hardware so good that it survived working correctly 47 years in a hostile environment, driven by a computer with the power of modern car key. Amazing.

You can agree with me or not

I agree with you entirely. I can not think of a single piece of tech with the complexity of Voyager that has been battle hardened and resilient to last that long, keep doing what it was designed to do without a major on-site overhaul, upgrade or tech refresh. Certainly not any of our current satellites or anything created since Voyager. I think I know why this will never occur again but that's a much bigger topic.

Re: 47-year-old Voyager 1 fired up thrusters it hasn't used in decades

#70

Post by greenavocado »

Rebelgecko wrote: post #13
albertopv wrote: post #4

Boeing could take notes /s

More like L3/Harris/Aerojet/Rocketdyne... They built Voyagers' thrusters as well as the Boeing Starliner's.

The German scientists that made the Apollo program and associated technology happen are long gone
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