Ever since its 2004 discovery, asteroid 99942 Apophis has threatened planet Earth.
At 1100 ft (340 meters) throughout, an influence would launch the energy equivalent of 1.2 Gigatons of TNT.
That’s ~100 occasions as energetic the Meteor Crater-creating influence.
Initially, observations indicated a 2% chance of a 2029 collision with Earth.
That alarmingly excessive likelihood arose from inadequate information.
In orbital mechanics, small positional uncertainties compound over time.
Gravitational encounters — together with with main planets — additional alter trajectories.
So do outgassing and interactions with unresolved objects.
Many high-resolution observations over lengthy timescales can allow correct predictions.
Now, in 2021, Apophis’s future trajectory is thought by way of 2029: inside ±2 km.
All potential impacts this century are confidently dominated out.
Still, many probably hazardous objects, plus unidentified threats, stay.
A doable 4479 collision could possibly be 28 occasions worse than the historic Chicxulub impactor.
Observational identification with well-characterized trajectories are required to enact mitigation plans.
The Vera Rubin Observatory may assist, however should overcome satellite tv for pc megaconstellation air pollution.
Otherwise, our destiny might be to endure unexpected damages, after which rebuild.
Detection and prevention provides the one catastrophe-free resolution.
Mostly Mute Monday tells an astronomical story in photos, visuals, and not more than 200 phrases. Talk much less; smile extra.