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The stratum of Space consist of various conditions and sometimes pecularities that are not so familiar to the typical Earth person. These conditions are mostly the various radiations that exist in Space but are blocked by the Earth’s atmosphere. The radiations in Space are studied in detail and become a major criteria for the design of space vehicles, deployable equipment, and EVA spacesuits. What could be thought peculiar about this “weather” in Space is the addition of finely ground rocks or natural debris ranging in sizes as small as 1mm but whizzing by at phenomenal speeds. These are called micrometeoroids. These are not meteors of the standards sought by CNEOS (Center for Near Earth Object Studies) which track significant asteroids and comets passing Earth. Micrometeoroids can hardly be seen and are considered “dust of the solar system”. The problem is if one these minute particles of rock have slung around a giant gas planet (or two) and head their way towards earthman’s space activities, which now days is somewhere between the Earth and Moon.

Such occurrence can explain mysterious equipment failures during an event such as an EVA. This is thought to explain a recent NASA spacesuit leak incident of June 2024 when an astronaut opened the hatch door of the International Space Station.

Although very small at 1mm, the mass of such particle is only one side of the story as seen from the kinetic energy equation:

The other side of the story is the squared term of this equation which allows velocity to contribute multiple factors to the total kinetic energy.

The small mass of these particles allows them to escape the pull of gravity of larger masses, left in a type of free-floating orbital motion, only to become accelerated by chance of another passing object, and perhaps by another object. If these particles happen to sling around a major planet, they will have built up enough acceleration to carry significant kinetic energy.

If a space vehicle is orbiting the Earth in one direction and a micrometeoroid enters Earth orbit travelling in the opposite direction, the event of a collison will consist of the addition of both velocities. If any portion of EVA equipment is left unprotected, even the smallest exposed crevice, it can be susceptible to this type of micrometeoroid event.

A micrometeoroid accelerated in the solar system enters Earth's orbit with velocity head-on to an orbiting spacecraft.

This accounts for small dust particles of about 10μm - 2mm, but what about meteors the size of a golf ball or baseball ? Aren’t these considered more dangerous, and how many of these exist ?

It must be kept in mind that the existence of our Earth was on a “time delay” since the event of the Big Bang, or beginning of the Universe. The Earth did not start forming and come into existence until 9.2 billion years after the Big Bang. This gives plenty of time for all the small rock debris to conglomerate into larger rocks, and these larger rocks conglomerate into even larger rocks, until eventually forming planets and exoplanets; or otherwise taken in by suns and stars to be disintegrated - until there are no more small rocks left behind. Small rock debris is easily gravitated into larger rocks to become planets, or disintegrated by stars, because they have a smaller momentum and can’t carry themselves through the Universe. Larger rocks, on the other hand, have a greater momentumand tend to continue on their original path, eventually orbiting other bodies instead of contacting them. This behavior is evident from Newton’s First Law of Motion and the presence of gravity. All the motions of today’s celestial objects can be accounted for by these two principles. There is a constant presence of gravity yet all motion has been preserved since the beginning of time. Although two major celestial bodies may be gravitated to each other they also want to remain on their original path of motion. This explains the existence of binary stars. Stars are major celestial bodies that may be approaching each other due to gravity but also want to remain on their original path. So instead of colliding or passing each other completely - a little of both occur - they attract each other but also want to pass each other. This results in a type of binary motion where they end up orbiting each other about a barrycentre. ¹

The Earth’s existence in the calendar of the Universe explains why we mostly have large asteroids and fine dust particles to deal with, and very little in between. Major asteroids mostly tend to go on their way and remain in established orbits due to their high mass and greater momentum², and the existence of fine dust are still free in Space because it has been so unattracted to anything else due to its very low mass.

When studied, the odds of impact with a micrometeoroid during Extra-Vehicular Activity show to be slim, and so the issue appears to subside. But although one can breathe a sigh of relief at the rare occurrence of encountering a micrometeroid, the favorable odds do not make the micrometeoroid disappear altogether. It is still out there.

The task is to collect ongoing data providing month-to-month (and week-to-week) predictions throughout a given year. In other words, the odds of micrometeor encounters during one time of the year will not be the same as another, or even from year-to-year. A major influencer are the meteor showers known to Astronomy³ (e.g., Perseid meteor shower) but these shouldn’t be relied on as the only criteria. There may be other patterns of meteor activity which can be spotted and detected having an entirely different origin.

.. the favorable odds do not make the micrometeoroid disappear altogether. It is still out there.

.. the calendar of the Universe explains why we mostly have large asteroids and fine dust particles to deal with, and very little in between.

1. When two objects of approximately equal masses orbit each other with neither being stationary nor dominant, they share a common barrycentre.

2. Linear momentum, or commonly stated momentum, is expressed as mv, the mass times its velocity.

3. Meteor showers radiate from various directions and there are about two dozen named showers given a rating of medium to bright. Names of some of these showers are Geminids, Perseids, Leonids, Orionids, and Lyrids. Overall, as of January 2024, there are 110 meteor showers known to Astronomy.