240 BC
Chinese astronomers record it. The oldest sure sighting.
Halley's Comet
12,698 days
until it comes back.
1986
- From the Sun
- 0.59 AU
- Speed
- 54.6 km/s
One lap, 1986 to 2061. Scroll is time.
Square-root distance scale. Planet positions illustrative.
1066
Stitched into the Bayeux Tapestry. Isti mirant stella: these men wonder at the star.
1301
Giotto sees it, then paints it as the Star of Bethlehem.
1758
Back on time, as Edmond Halley predicted. He had died sixteen years earlier.
1910
Earth passes through the tail. Mark Twain, born in the 1835 visit, dies the day after perihelion.
1986
The probe Giotto flies 596 km from the nucleus.
2061
Next.
May 1910
Earth passes through the tail.
Its spectrum shows cyanogen gas. Shops sell comet pills.
600,000 km
to the nucleus
14 March 1986. Giotto, closing at 68 km/s.
15 × 8 km
The nucleus. A dusty ice lump, darker than coal.
It sheds dust every lap.
Earth crosses that dust twice a year.
- Eta AquariidsMay
- OrionidsOctober
In 2061 you'll be