129839 1999 RH21 (Asteroid)
From South El Monte , 129839 1999 RH21 is visible in the morning sky, becoming accessible around 20:54, when it reaches an altitude of 21° above your north-eastern horizon. It will then reach its highest point in the sky at 02:33, 89° above your southern horizon. It will be lost to dawn twilight around 05:11, 57° above your western horizon.
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                    Name
                    129839 1999 RH21                 
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                    Object type
                    Asteroid                 
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| Computed for: | 04 November 2025 | 
| Right ascension: | 05h37m [1] | 
| Declination: | +33°59' [1] | 
| Constellation: | Auriga | 
| Magnitude: | 19.96 (V) [1] | 
| Distance: | 1.58 AU 13.11 lightmin [1]  | 
| Angular motion (speed): | 22.49 arcmin/day[1] | 
| Angular motion (pos ang): | 267.6° | 
| Semi-major axis: | 2.63 AU | 
| Eccentricity: | 0.202580 | 
| Inclination: | 7.93° | 
| Longitude ascending node: | 6.67° | 
| Argument of perihelion: | 347.54° | 
| Epoch of elements: | 25 January 2025 | 
| Mean Anomaly at epoch: | 347.46° | 
| Absolute mag (H): | 16.18 [1] | 
| Slope parameter (G): | 0.15 [1] | 
| Perihelion: | 2.09 AU | 
| Aphelion: | 3.16 AU | 
| Orbital period: | 4.25 years | 
All times shown in South El Monte local time.