99942 Apophis (2004 MN4)
Tracked by NASA JPL Near-Earth Object Web Service (NeoWs), 99942 Apophis (2004 MN4) is a Sq body measuring between 340m and 340m in diameter. On 2029-04-13, it completes a cislunar approach at 0.10 Lunar Distances (38,011 km) with a relative heliocentric velocity of 7.42 km/s.
99942 Apophis (2004 MN4) (JPL ID 99942) is a Sq Near-Earth Asteroid spanning 340.0m–340.0m (mean 340m). On 2029-04-13, it transits Earth's cislunar surveillance sector at 0.099 Lunar Distances (38,011 km) with a relative velocity of 7.42 km/s and a theoretical kinetic energy reserve of 385.89 megatons TNT. Classified as a Potentially Hazardous Asteroid (PHA) due to its Minimum Orbit Intersection Distance (MOID <= 0.05 AU) and absolute magnitude (H <= 22.0), it remains under high-priority radar and optical astrometric tracking.
Exact Landmark Scale Comparison (340m)
Kinetic Impact Physics & Orbital Parameters
99942 Apophis (2004 MN4) (H = 19.1, Vmag ≈ 3.8) is below consumer optical detection thresholds (requires ≥1000mm survey aperture); explore certified meteorite specimens[↗] or indoor optical projection instead.
Campo del Cielo Meteorite Specimen (Certified Iron-Nickel)
Authentic coarse octahedrite Group IAB iron-nickel meteorite fragment (92.9% Fe, 6.7% Ni) recovered from the Chaco crater field with certificate of authenticity.
Satin-black 5W warm-white LED optical glass lens planetarium projecting 60,000 stars and simulated meteor shower trajectories indoors.
3D Ephemeris Trajectory Waypoints
Planetary Defense Frequently Asked Questions (Schema.org FAQ)
How big is 99942 Apophis (2004 MN4) compared to city landmarks?
99942 Apophis (2004 MN4) has an estimated diameter between 340m and 340m. At its upper-bound size of 340m, it stands 77% as tall as the 443m Empire State Building in New York City and 103% of the 330m Eiffel Tower.
What does the stored 2029-04-13 close-approach estimate show?
This catalog snapshot lists a nominal miss distance of 0.10 Lunar Distances (38,011 km) for 99942 Apophis (2004 MN4). This is not an impact prediction; check the latest NASA JPL record for updated orbital estimates. The 3D impact simulation is hypothetical.
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Authentic coarse octahedrite Group IAB iron-nickel meteorite fragment (92.9% Fe, 6.7% Ni) recovered from the Chaco crater field.
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