Comet NEOWISE
The brightest comet of the 2020s so far for northern observers, discovered by a space telescope hunting asteroids.
Key facts
- Designation
- C/2020 F3 (NEOWISE)
- Type
- Long-period comet
- Orbital period
- several thousand years
- Closest to the Sun
- 0.29 AU (about 44 million km)
- Farthest from the Sun
- a few hundred AU
- Tilt of orbit
- about 129° (retrograde)
- Nucleus
- about 5 km across
- Discovered
- by the NEOWISE space telescope on 27 March 2020
- Returns
- passed closest to the Sun on 3 July 2020 and closest to Earth on 23 July 2020
Orbit
Comet NEOWISE came in from far beyond the planets on an orbit tilted steeply to theirs. It passed the Sun inside Mercury's orbit on 3 July 2020 and then swung north, becoming easy to see from Europe and North America through July. It passed Earth at about 103 million km, a safe distance. Its next return will be several thousand years from now.
Size and nature
The nucleus is about 5 km across. Many comets that pass so close to the Sun break up, but NEOWISE survived. At its best it was about magnitude 1 and showed a curving yellow dust tail and a fainter blue gas tail. Photographs revealed fine bands in the dust tail, made as the rotating nucleus threw out dust in bursts.
History
The NEOWISE space telescope, a former infrared astronomy satellite given a new task of finding asteroids, picked it up in March 2020 by its warmth. Few expected it to become bright, but it did, at a time when many people were at home during the pandemic and looked up. It was the brightest comet seen from the northern hemisphere since Hale–Bopp in 1997.
Meteor showers
The comet's orbit does not come close enough to Earth's for a shower.
Missions
NEOWISE itself is the comet's namesake. The SOHO and Parker Solar Probe spacecraft also photographed it near the Sun, and the International Space Station crew saw it from orbit.
Space missions
- NEOWISE An infrared telescope that measured the sizes of tens of thousands of asteroids.
- SOHO A solar observatory that has become the greatest comet discoverer in history.
Key dates
| Date | What happened |
|---|---|
| 27 March 2020 | The NEOWISE space telescope discovered Comet NEOWISE. |
| 3 July 2020 | Comet NEOWISE passed closest to the Sun. |
| 23 July 2020 | Comet NEOWISE passed closest to Earth, at about 103 million km. |
Did you know?
It is the brightest comet the NEOWISE telescope found.
Its tail showed a striped pattern caused by the spinning nucleus.
It was visible in the evening and morning sky at once from Britain in mid-July 2020, as it circled near the Pole.