Temporarily Captured Orbiters (a.k.a. Mini-moons)

My interest in searching for serendipitous images of meteoroids branched unexpectedly when it became obvious that some meteoroids impact our atmosphere at very low speeds.  The minimum speed that a solar system object will hit our atmosphere is approximately 11.2 km/s.  This corresponds to the speed an object would have if you held it stationary with respect to the Earth at a very large distance (say the distance to the Moon or more), and let it "drop" to the Earth.

Angela's Remembrance Service

The full text, song lyrics and remembrances of Angela's Service.

Mercury Retrograde Motion

Amidst all the angst over fearsome Friday of June 13, 2014 (full moon on a Friday the 13th), an RASC colleague mentioned on our email list that there was additional concern being expressed around this all happening while Mercury was in retrograde motion.  Well, its harmless, it happens all the time, but it still was fodder for yet another animation.  As the Earth orbits the Sun, the Sun and the planet appear to drift across the stars from West to East, or right to left in the animation.

Mercury Retrograde Motion

Near Earth Asteroid 2015 TB145 Fly-By

In the evening of October 31, this Near Earth Asteroid (NEA) speeds past the Earth at about 1.2 lunar distances. What is particularly interesting about this asteroid is it highly inclined orbit, bringing it from well below the plane of the Solar System, up over the Moon and Earth to begin its brief visit to the inner Solar System. Looking an both size (approx 400 m diameter) and how close it comes to Earth, this is a once in a decade event.

Near Earth Asteroid 2015 TB145 Fly-By

August 2017 Eclipse over North America

One struggle with animating eclipses is trying to come up with the line of sight that best demonstrates the various motions and shadow shapes involved. The things I try to capture are the teardrop area of partial eclipse, the shortening then elongating ellipse of totality, the movement of the Moon’s shadows in the combined motions of the Earth orbiting the Sun and the Moon orbiting the Earth, and the Earth’s rotation, unfortunately in the same direction as the motion of the shadows.

August 2017 Eclipse over North America

April 2024 Eclipse over Ontario & Quebec

After doing an animation of the August 2017 eclipse over North America, I was asked to do a similar simulation of the April 2024 eclipse. The area of totality of this eclipse skirts just south of London Ontario, and Toronto, and just kisses the fine city of Montreal. As with the prior simulation, this viewer of this scene is travelling along with the Earth with the line of sight pointing at London. The viewers position with respect to the Earth is fixed, so the Earth rotates below the viewer.

April 2024 Eclipse over Ontario & Quebec

The Minor Planets

There are well over 600,000 catalogued minor planets in our solar system, most being the asteroids of the asteroid belt between the orbits of Mars and Jupiter.  Here is a view of the majority of minor planets, showing the asteroid belt, the many asteroids inside Mar’s orbit which  are of interest due to their proximity to Earth, and the two clusters of Jupiter Trojans which orbit the Sun near the magical Jupiter Lagrange points 60° on either side of Jupiter.

The Minor Planets

Lunar Interaction with EN130114 TCO Meteoroid

On January 13, 2014, cameras in the Czech Republic observed such an object as a fireball.  After some modelling of the  atmospheric behaviour of the object by Pavel Spurný and Jiří Borovička, I calculated the possible trajectories of the object; what was found was very interesting....  The point in this animation are possible "probability clones" for the object.  There are so many of these clones because we have to account for measurement uncertainties.  These clones cover that uncertainty.

Lunar Interaction with EN130114 TCO Meteoroid

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