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Incoming Asteroid
The bottom ones are also potentially bad news for any other planets in our solar system that have been counting on Earth having a stable orbit.
Title text: The bottom ones are also potentially bad news for any other planets in our solar system that have been counting on Earth having a stable orbit.

Explanation

Ambox notice.png This explanation is incomplete:
Created by an incoming bearer of bad news - List should probably be in a table, which should probably be done by someone with experience in creating tables. Do NOT delete this tag too soon.

This comic may be inspired by the recent discovery of asteroid 2024 YR4, which, on the date of the comic (February, 10, 2025), was estimated to have about 1-in-48 chance of striking Earth on December 22, 2032. Its size is estimated to be 40-90 meters. Currently, it is rated a 3 on the Torino scale, a metric designed to evaluate the danger of a potential strike from a near-Earth object.

This comic provides a log scale correlating the size of any incoming asteroid to whether its arrival is good or bad news. While asteroids on the smaller end of the scale are good news for sky watchers, as the upcoming objects get bigger, the potential for catastrophe grows. Many astronomy enthusiasts would be happy to see bigger meteors, as bigger generally means more exciting pictures. Of course, once the meteors grow past a certain size even the most enthusiast astronomer might grow concerned about their imminent extinction.[citation needed]

The title text adds an additional point about asteroids on the lower end of the scale, which have enough mass to change Earth's orbit. If it changed enough it might intersect the orbit of other planets (probably Venus or Mars, since those are the closest). This might lead to Earth colliding with that planet. Also, even without a collision, the changed orbit might perturb their orbits due to the Earth's gravitational force and cause negative consequences by either invoking or revoking orbital resonances between the various inner planets.

List of sizes and consequences

Sizes are approximate.

1 cm: Good news! Meteors are pretty! Nothing more than a streak in the sky.
30 cm: Great news! You might see a fireball! Might descend far enough for the flames of its entry to be visible with the naked eye (bolide).
3 m: Okay news, unless you have expensive windows or are very unlucky. Can descend far enough for the shockwave of its passing to shatter windows. The comic mockingly claims this is only a problem if your windows are expensive or happen to get directly hit by it. Of course, the shattering windows are also concerns for safety[citation needed], as the Chelyabinsk meteorite, which sits near the upper bound of this category at approximately 18 m in diameter, damaged more than 7,000 buildings and injured around 1,500 people with its shockwave.
60 m: Bad news, especially if you live near the city it's aimed at. The Tunguska meteor, which flattened and burnt over 2,000 km2 of Siberian forest in 1908, was 50-60 m across. It would have been rated an 8 on the Torino scale as a certain collision with localized destruction.
600 m: Bad news, especially if you live on the continent it's aimed at. Can easily cause localized extinction, and can be expected to have effects on the rest of the world as well.
9 km: Bad news for your species. The Chicxulub asteroid that wiped out non-avian dinosaurs was about 10 km in diameter.
50 km: Bad news for your phylum. Our phylum is primarily all the vertebrate animals.
300 km: Bad news for your biosphere. A global extinction event is pretty much guaranteed.
2,000 km: Good news for any life that might someday evolve on Earth's new moon. Earth's moon is believed to have been formed when Earth, in its infancy, was hit by an object of roughly this size. The comic assumes that another moon would form from another such impact, hypothesizes that life might evolve on that moon, and pretends that it's good news.
25,000 km: Bad news for whatever planet is about to get hit by Earth. At this size, the "asteroid" is over twice as large as Earth itself (whose diameter is about 12,700 km) and would likely be classified as a planet. (Unofficially, at least. Officially, there would be quibbling about whether it had "cleared its neighborhood." Briefly. [citation needed]) At that point, the comic points out, it would be more accurate to describe the Earth crashing into the "asteroid"/planet, not the other way around.

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Header:]
An asteroid is headed straight for Earth! That's...
[A log scale of lengths is shown, labelled "Asteroid size", with markings of 1 cm, 10 cm, 1 meter, 10 meters, 100 meters, 1 km, 10 km, 100 km, 1,000 km, and 10,000 km. The remaining lines of text are at various points down the scale.]
...Good news! Meteors are pretty!
...Great news! You might see a fireball!
...Ok news, unless you have expensive windows or are very unlucky.
...Bad news, especially if you live near the city it's aimed at.
...Bad news, especially if you live on the continent it's aimed at.
...Bad news for your species.
...Bad news for your phylum.
...Bad news for your biosphere.
...Good news for any life that might someday evolve on Earth's new moon.
...Bad news for whatever planet is about to get hit by Earth.


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