Top 10 Misconceptions about our Solar System
Do you think you know what’s what about our Solar System? I'm Humblebee
and you’re watching Astrum. We’re going to count down the top ten misconceptions
about our Solar System. Let’s see if you believed any of these before watching this!
10. The Sun is a burning ball of fire. The Sun is glowing, not burning like a fire.
The Sun glows because its temperature is about 5,500 degrees Celsius. This heat is not produced
by burning (a chemical reaction), but rather by fusion (a nuclear reaction). This nuclear
fusion takes place deep in the Sun’s core at a temperature of about 15 million degrees.
As the heat travels out through the Sun’s layers, it becomes much cooler, but still
very much hot enough to glow in visible light. Now, while 5,500 degrees seems cool compared
to 15 million degrees, that’s still hot enough to melt most metals. Just to give a
comparison, a wood fire burns at about 500 degrees.
9. Pluto is the most-distant and last object in the solar system.
Pluto resides within a region of icy objects called the Kuiper Belt. The Kuiper Belt extends
from Neptune’s orbit outward. Beyond Pluto's orbit is another vast region of icy objects
called the Oort Cloud, which, like the Kuiper Belt, is a home to icy comets. There’s even
three dwarf planets that we know about that are further, and some even bigger than Pluto.
There’s Haumea, Makemake and Eris. Eris is currently about 3 times as far
away from the Sun as Pluto. 8. Saturn is the only planet with rings.
While many of us were taught in school that Saturn had amazing rings, made up of small
rocks, ice and other particles, there are actually several other planets that also have
rings around them. In fact, all of the larger planets in the solar system have been found
to have rings. This is true of Jupiter—whose rings cannot be seen from our planet—as
well as Neptune. Even Uranus has nine bright rings around it, as well as a few fainter
ones—but all of these are difficult to see, due to the distance.
7. Comets come from regions outside the solar system.
Comets are part of the solar system. Scientists believe they come from one of two locations
within the solar system: the Kuiper Belt and the Oort Cloud. The comets that we see often
– every 100 years – come from the Kuiper Belt, and comets that we see rarely – every
few thousand years – come from the Oort Cloud.
6. Asteroids in the Asteroid Belt are very close to each other.
Thanks to Star Wars and other Hollywood space movies, we have the impression that asteroids
are always bashing into each other and spaceships would have a hard time navigating an asteroid
field. Asteroids though are not close to each other. The asteroid material is so thinly
distributed that numerous unmanned spacecraft have traversed it without incident. On average,
they are roughly 1 million miles from each other, and the total mass of the asteroid
belt is only just 4% of the mass of the Moon. 5. Mercury is tidally locked to the Sun like
the Moon is to Earth. For many years it was thought that Mercury
was synchronously tidally locked with the Sun, rotating once for each orbit and always
keeping the same face directed towards the Sun, in the same way that the same side of
the Moon always faces Earth. Radar observations in 1965 proved that the planet has a 3:2 spin–orbit
resonance, rotating three times for every two revolutions around the Sun. The original
reason astronomers thought it was tidally locked was that, whenever Mercury was best
placed for observation, it was always nearly at the same point in its 3:2 resonance, hence
showing the same face. This is because, coincidentally, Mercury's orbit takes almost half the time
Earth takes to orbit the Sun. Due to Mercury's 3:2 spin–orbit resonance, a solar day (from
sunrise to sunrise) lasts about 176 Earth days. A sidereal day (the period of rotation)
lasts about 58.7 Earth days. 4. Mercury is the hottest planet in the Solar
System. While it is sensible to think that Mercury
is the hottest planet due to it being the closest planet to the Sun, it’s just simply
not true. It turns out that Venus is actually a hotter planet than Mercury, even though
it is further away. The reason for this is that Mercury doesn’t have an atmosphere
(because it’s so close to the Sun) which means that there is nothing to hold the heat
in. Venus, on the other hand, has a notoriously thick atmosphere that traps the heat created
by the sun. The max temperature you’ll find on Mercury is 426 degrees c, while the average
temperature on Venus is 462 °C. 3. The Sun only accounts for a small part
of what’s in the Solar System. I’m sure you guessed the Sun is big. But
the sun actually makes up over ninety-nine percent of all of the mass in our entire solar
system. Jupiter and some of the other large planets make up most of the rest, and Earth
barely even registers in the equation. We can be glad the Sun is as large as it is though,
as it makes everything in the solar system work – giving us light, heat and energy
– while holding everything together in their orbits using its massive gravity.
2. Comets always have tails. Comets do not always have tails. They develop
a fuzzy, shell-like cloud called a coma, and one, two, or three tails when near the Sun.
A comet tail and coma are illuminated and may become visible from Earth when a comet
passes through the inner Solar System, the dust reflecting sunlight directly and the
gases glowing from ionisation. Interestingly, while the solid nucleus of comets is generally
less than 50 km across, the coma may be larger than the Sun, and ion tails have been known
to extend 3.8 astronomical units (355 million mi). Also, the tail will always point away
from the Sun. Comets have no coma or tail when far away from the Sun.
1. The Solar System formed during the Big Bang, along with the rest of the Universe.
The Solar System is a lot younger than the universe. According to scientific research,
the current estimate of the age of the universe is 14 billion years, while it is believed
that the Solar System is only 4 and a half billion years. The Solar System is
said to have formed from the gravitational collapse of a giant molecular cloud, most
of which became our Sun, the rest forming everything else found in the Solar System.
What other misconceptions have you heard about our Solar System? Post in the comments below.
Be sure to check out my channel here and if you liked this video to share and to subscribe
to Astrum. Thanks for watching!