2023 FW13

2023 FW₁₃ is an asteroid that was spotted on March 28, 2023, from the Pan-STARRS telescope at Hawaii, United States. It circles the sun in sync with Earth in such a way that it appears to orbit Earth, but well outside Earth's Hill sphere, making it a quasi-satellite.^[3]

2023 FW₁₃

Discovery [1]
Discovered by	Pan-STARRS
Discovery site	Haleakala Observatory
Discovery date	28 March 2023
Designations
MPC designation	2023 FW13
Minor planet category	NEO Apollo [2][1] Earth quasi-satellite [3][4]
Orbital characteristics [2]
Epoch 26 February 2023 (JD 2460000.5)
Uncertainty parameter 0
Observation arc	10.86 yr (3,967 d)
Aphelion	1.1781 AU
Perihelion	0.8225 AU
Semi-major axis	1.0003 AU
Eccentricity	0.1777
Orbital period (sidereal)	1.0005 yr (365.42 days)
Mean anomaly	73.09°
Mean motion	0° 59m 6.601s / day
Inclination	2.7441°
Longitude of ascending node	70.557°
Argument of perihelion	354.40°
Earth MOID	.0454762 AU (6,803,140 km; 17.6979 LD)
Physical characteristics
Absolute magnitude (H)	26.01[2] 26.10[1]

The orbit of 2023 FW₁₃ has a one-to-one resonance with Earth and is very eccentric, reaching out halfway to Mars and halfway to Venus.^[4] It's estimated that it has circled Earth since 100 B.C. and will continue until 3700 A.D. If those estimates are correct, it would significantly overtake 469219 Kamoʻoalewa as the most stable quasi-satellite of Earth.^[4]