Voyager 1: One Light-Day From Earth
At 10:16 UTC on Wednesday 18 November 2026, Voyager 1 becomes the first spacecraft ever to be a full light-day from Earth: 25,902,068,371 km away, so far that its radio signals take 24 hours to reach us.
until 10:16 UTC on Wed 18 Nov 2026
What happens on 18 November 2026
A light-day is the distance light travels in 24 hours: 25,902,068,371 km, about 173 times the distance between Earth and the Sun. Voyager 1 reaches that distance from Earth at 10:16 UTC on Wednesday 18 November 2026, the first object people have ever sent so far.
Nothing changes on board. Voyager 1 keeps coasting outwards at about 60,905 km/h, as it has since it swung past Saturn in 1980. What changes is the conversation: from then on, every command sent from Earth takes more than a day to arrive, and every reply takes more than a day to come back.
NASA's mission team gives the same moment: 2:16 a.m. Pacific time (5:16 a.m. Eastern, 10:16 a.m. in London).
One light-day in perspective
Light from the Moon reaches us in just over a second. From Voyager 1 it takes almost a full day. Each bar shows how long light takes to cross the gap from Earth; every step along the scale is ten times further than the last.
Distances are measured from Earth right now, except the heliopause: Voyager 1 crossed that boundary of the Sun's bubble in August 2012, about 121.6 times the Earth-Sun distance from the Sun.
Why some reports say 17 or 19 November
Three moments fall within two days of each other, and each is a fair way to describe the milestone:
A command sent from Earth takes a full 24 hours to reach Voyager 1, because the spacecraft keeps moving away while the signal travels.
Voyager 1 is exactly one light-day from Earth. This is the moment NASA gives, and the one this countdown uses.
A signal leaving Voyager 1 takes a full 24 hours to reach Earth.
Will it drop back below one light-day?
No. As Earth circles the Sun it swings towards Voyager 1 and away again, so the distance grows fast in some months and shrinks a little in others. After 18 November it grows until about 21 January 2027, shrinks slightly until about 25 April 2027, then grows for good. Even at that lowest point Voyager 1 is about 27 million km beyond one light-day.
Measured from the Sun rather than from Earth, Voyager 1 reaches one light-day around 3 February 2027.
What comes next
One light-day from the Sun.
Voyager 2 reaches one light-day from Earth, long after it is expected to fall silent.
Voyager 1 reaches two light-days from Earth.
It reaches the inner edge of the Oort Cloud, the vast, distant shell of icy bodies around the Sun. Crossing it could take some 30,000 years.
It is one light-year from Earth.
It passes within 1.6 light-years of the star Gliese 445.
Is Voyager 1 still working?
Yes. Voyager 1 still sends science data from two instruments, its magnetometer and its plasma wave instrument, at 160 bits per second. To save power, the cosmic ray instrument was switched off on 25 February 2025 and the low-energy particle instrument on 17 April 2026. Its plutonium power supply loses about 4 watts a year, and NASA expects at least one instrument to keep working into the 2030s.
The most distant human-made objects
Five spacecraft are on their way out of the Solar System. Only the two Voyagers and New Horizons still talk to Earth.
| # | Spacecraft | From the Sun | Light-time from Earth | Status |
|---|---|---|---|---|
| 1 | Voyager 1 | 25.76 billion km 172.2 AU | 23 h 57 min | Working |
| 2 | Voyager 2 | 21.59 billion km 144.3 AU | 20 h 02 min | Working |
| 3 | Pioneer 10 | 21.26 billion km 142.1 AU | 19 h 36 min | Silent since 2003 |
| 4 | Pioneer 11 | 17.67 billion km 118.1 AU | 16 h 25 min | Silent since 1995 |
| 5 | New Horizons | 9.86 billion km 65.9 AU | 9 h 10 min | Working |
Questions people ask
At 10:16 UTC on Wednesday 18 November 2026 (2:16 a.m. in California, 5:16 a.m. in New York, 10:16 a.m. in London). It will be the first spacecraft ever to be that far from Earth.
One light-day is the distance light travels in 24 hours: 25,902,068,371 km, or 16.09 billion miles. That is about 173 times the distance between Earth and the Sun.
Right now 23 h 57 min each way, so a command and its reply take about two days. The delay grows by about 9.7 seconds every day.
Only in about 18,000 years. A light-year is 365 times further than a light-day, and Voyager 1 travels about 3.6 times the Earth-Sun distance each year.
They describe slightly different moments. From about 18:15 UTC on 17 November a command sent from Earth takes 24 hours to reach Voyager 1; at 10:16 UTC on Wednesday 18 November 2026 its distance from Earth reaches one light-day; and from about 02:15 UTC on 19 November its signals take 24 hours to reach Earth.
About 60,905 km/h (37,844 mph) relative to the Sun. Seen from Earth the distance grows faster in some months than others, because Earth itself circles the Sun.
Around 2035. Voyager 2 is 20 h 02 min of light-travel time from Earth today, and it is expected to have fallen silent long before it gets there.
No. Voyager 2 is the next most distant, 20 h 02 min of light-travel time away, followed by Pioneer 10 and Pioneer 11, which fell silent decades ago, and New Horizons.
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