Near-Earth Object
474158 (1999 FA
NASA ID: 20474158
474158 (1999 FA will pass Earth on 4 March 2027 at a distance of 16.52 lunar distances (LD) - about 6,350,110 km - travelling at 23,860 km/h. Its estimated diameter is between 192 and 429 metres, roughly the size of The Shard in London (310 m tall). NASA classifies it as a potentially hazardous asteroid (PHA) - a designation based on size and orbital proximity, not on any predicted impact.
Close Approach Date
4 March 2027
In 121 days
Miss Distance
16.52 LD
6,350,110 km
17 times the Moon's distance from Earth
Velocity
23,860 km/h
0.9 times the orbital speed of the International Space Station
Est. Diameter
192–429 m
Absolute Magnitude
H = 20.71
The brightness measure astronomers use to estimate size
Hazard Classification
Potentially Hazardous
A watch-list label based on size and orbit, not a predicted impact
The real orbit in 3D
The actual path of 474158 (1999 FA around the Sun, computed from JPL orbital elements. Drag to rotate, scroll to zoom, and use the time controls to run the orbit forwards or back.
Every recorded pass
Each dot is one close approach of 474158 (1999 FA to Earth between 1909 and 2095, from JPL's records. Lower means closer: a dot under the dashed line passed nearer than the Moon. The orange dot is the approach on this page.
Size Comparison
Reading the Numbers
- A lunar distance (LD) is the average gap between Earth and the Moon, about 384,400 km. It is the standard yardstick for close approaches. Read more →
- Diameter estimates come from brightness. A dark surface reflects less light than a bright one, so the true size can sit anywhere in the quoted range. Read more →
- Potentially hazardous is a watch-list label based on size and orbital proximity. It does not mean an impact is expected. Read more →
