...and certainly not the last ! Some asteroids deserve special attention, and this one is among the top of the list, not because of its characteristics (merely 350 meters across), but because of its orbit, that brings it close to Earth, too often, and maybe too close...
On the evening of March, 5th, Apophis cruised off our planet, at a respectable distance of over 16,000,000 km (some 10 million miles), that made a good opportunity to watch it, safely !
The apparent magnitude of 15.5 was bright enough to allow us to see it visually through our telescopes and, why not, to capture its relatively fast motion among the star field (apparent motion was estimated at 3.5 arcsec. per minute) in the constellation of Hydra.
We took a series of pictures at intervals of 2 minutes only, and still they clearly show a tiny dot shifting from one to another : that's Apophis ! Here we display some of them, with the asteroid identifyed by the red mark: (North is up for all the views)
Click on the pictures to enlarge and watch them in a presentation mode as to see the motion effect
The picture below shows the path of the asteroid on that night (roughly from 22h00 to 03h00, local time), with the previous position circled:
And here is another series of pictures, spanning approximately an entire hour:
Apophis will make an extremely close "flyby" on April 2029, approaching at only 36,000 km from Earth centre (that is, some 30,000 km from the surface!), then again another close pass in 2038... In first instance, there was a small probability of collision for 2038, now definitely ruled out by the most accurate calculations. However, these same calculations arise a risk of collision for 2068, although we may not worry yet : the orbit of Apophis will be affected by the gravitational field of Earth during its 2029 flyby, hence the definitive trajectory cannot be established until then...
Photos: Cristian Valenzuela / Observatorio del Pangue - March, 2021.
