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| ▲ | busymom0 3 days ago | parent | next [-] |
| Can you provide some details on how we on earth are able to pick up such a signal amongst all the noise? |
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| ▲ | wkat4242 3 days ago | parent | prev | next [-] |
| 0.3 degrees is pretty narrow :) I would not consider that "in the general direction". |
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| ▲ | dylan604 3 days ago | parent | next [-] | | .3° at 25B km is still a pretty large distance. Some random calculator online says that would be 1.3090e+8 kilometers or 130,900,000km. The earth-moon distance is roughly 240,000km. 1AU ~= 149,597,900 So .3° is just under 1AU, and essentially to cosmological scales .3° = 1AU. And it's only getting bigger as it continues to get further away. So essentially, just point at the sun and it'll hit earth | | |
| ▲ | pipe01 2 days ago | parent [-] | | Of course, the sun will amplify the radio waves! | | |
| ▲ | dylan604 2 days ago | parent [-] | | What the huh? That's not even funny if I tilt my head sideways and squint at it. | | |
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| ▲ | 317070 2 days ago | parent | prev [-] | | The apparent size of the moon is 0.5 degrees. So 0.3 degrees is not _that_ narrow. You can point your finger at the moon. |
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| ▲ | stogot 3 days ago | parent | prev [-] |
| How does it locate earth to .3 accuracy while they’re both moving ? |
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| ▲ | 317070 2 days ago | parent [-] | | Voyager is so far away that from its perspective, earth isn't moving. There is also no force acting on voyager. So practically speaking, compared to the distance between them and the 0.3° beam width, both are hanging pretty still. It does have an AACS system, which is tracking the sun and a bright star (Canopus) to orient itself earlier in the mission. A quick search indicates it is still doing about 1 puff per hour to keep pointing the right way. The biggest problem seems to be that the lines for those puffs are clogging. |
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