99942 Apophis (2004 MN4)
Tracked by NASA JPL Near-Earth Object Web Service (NeoWs), 99942 Apophis (2004 MN4) is a Sq-type (Silicate / Nickel-Iron) body measuring between 310m and 375m in diameter. On 2029-04-13, it completes a cislunar approach at 0.10 Lunar Distances (38,012 km) with a relative heliocentric velocity of 30.73 km/s.
Exact Landmark Scale Comparison (375m)
Kinetic Impact Physics & Orbital Parameters
99942 Apophis (2004 MN4) (H = 19.7, Vmag ≈ 4.5) 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 310m and 375m. At its upper-bound size of 375m, it stands 85% as tall as the 443m Empire State Building in New York City and 114% of the 330m Eiffel Tower.
Will 99942 Apophis (2004 MN4) impact Earth during its 2029-04-13 approach?
No. NASA JPL Center for Near-Earth Object Studies (CNEOS) orbital solutions confirm 99942 Apophis (2004 MN4) will pass safely at a minimum distance of 0.10 Lunar Distances (38,012 km). You can still simulate a hypothetical street-level impact in our 3D CesiumJS simulator.
High-transmission BaK-4 Porro prism 15x70 optics with tripod adapter for bright near-Earth flybys, comets, and bolide shower radiants.
Autonomous apochromatic triplet smart telescope with integrated plate-solving, live stacking, and dual-band filter for magnitude 10–16 NEOs.
Ultra-portable Sony IMX678 starlight tele-camera with AI equatorial tracking and automated asteroid field stacking.
Authentic coarse octahedrite Group IAB iron-nickel meteorite fragment (92.9% Fe, 6.7% Ni) recovered from the Chaco crater field.
Low-read-noise Sony STARVIS 2 CMOS planetary and all-sky meteor bolide detection camera with 2.0μm pixels.