The phrase "earth changes" is often used to refer to some kind
of disastrous event that will adversely affect much if not most
life on Earth, including human life. There is thought about
preparing ourselves for it, but the phrase is vague about what
it could be.
Among the kinds of CMEs that can severely threaten much of the
life on Earth are the coronal proton ejections (CPE) or Solar
Proton Events (SPEs) that have have appeared to have
occurred several times in history. One such event today could
wipe out much of humanity and leave the Earth devastated. It
could bring radiation, massive wildfires, and other destructive
It differs in severity from coronal mass ejections like the
Carrington event of 1859, Those are CMEs, but do not in general
threaten life rather than power grids, which could be
devastating enough in this modern age of dependence on
electronic devices of all kinds. There are calls such as the
Shield Act to harden electric grids against them.
The main suspected SPE impacted the earth about 12,900 years
ago. There may have two such events, 12,837 years BP and 12,639
years BP. They could have been a principal cause of the final
termination of the Pleistocene megafauna and even of several
genera of smaller mammals and birds. There is also evidence of
less intense event in 2012 that missed the Earth by only two
weeks. One of the things that it does that could cause mass
extinctions is to raise the level of proton bombardment to fatal
levels. They are also suspected of causing massive, planet
Type G stars like the sun are not observed to produce massive
flares such as the one hypothesized to have harmed life on
Earth. The only stars observed to do that are type "T Tauri"
stars, but those stars are young, only about 100 million years
old. They are generally composed of almost pure hydrogen, with
little helium or traces of heavier elements. They are typically
surrounded by rings of debris, thought to be primordial planets.
The sun is about 4.6 billion years old. It contains helium and
other heavy elements. T Tauri stars flare frequently and
massively. But it seems unlikely that the sun would revert to a
T Tauri phase.
There does not appear to be evidence of previous proton storms
that could have caused mass extinctions. The 12,900 year old
labrean (named after the tar pits that captured so many of the
species that went extinct) extinction appears to have been a
A mistake made by some investigators is to call the solar
protons "cosmic rays", which are also mostly protons, but much
more energetic and moving at nearly the speed of light. Solar
protons are produced steadily, and largely comprise the "solar
wind" that can damage equipment and deliver near-lethal doses of
radiation to astronauts. But flares of solar protons can be
detected while they are still hours away, and astronauts can
take enough cover in compartments shielded by fuel and supplies.
Such shielding is not enough for cosmic rays.
This is why planned colonies on Mars are going to need to build
underground, to shield colonists from radiation.
Grazing rogue planets
There are interstellar objects that might make a grazing contact
with the sun, We recently had one such object, Oumuamua, an
odd-shaped body about ten times longer than it was wide, with
other strange attributes. The general name for interstellar
planets, not bound to a particular star, is rogue planet. Most
of them are expected to be round. They could be as large as
Jupiter. The term usually applies to a rocky object, perhaps
with a hot core, that could wander among the stars, and could
provide a site for an outpost for star travelers, if the core is
hot enough to geothermally support such an outpost. Grazing the
sun could produce a proton flare large enough to become a mass
A rogue planet with enough of an infrared signature could be
detected when it it still 100 billion miles from the sun, if we
were looking for it. If it were moving at the speed of the
fastest known star, 26 million miles an hour, it would close on
the sun in about 4000 hours, or about 6 months. That would be
enough time to find or build shelters for much of the human
population, but not enough to protect most wildlife.