The Solar System is not like You think it is [Video]

The Earth is round, Mercury is the hottest planet, and the Sun is yellow. It would seem that these are all simple, undeniable facts known even to those with no real knowledge about astronomy.

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  1. Chandravanshi Sunday Facts

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2. BlackBoard Sunday Facts

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However, it’s time to think again. We at Bright Side have put together a selection of the most common mistaken assumptions about the Solar System together with the true facts that expose them as false.

It Turns Out That the Solar System Is Not at All Like We Think It Is

This is true, yet paradoxically not true at the same time.

The shape of our planet is constantly changing due to the unending movement of the continental plates. Of course, the rate at which they move is very small — on average about 5 cm a year. But this still has an effect on the planet’s “appearance,” which is, in fact, far from perfectly round.

It Turns Out That the Solar System Is Not at All Like We Think It Is

The Solar System is not like You think it is [Video]

However, it should be pointed out that the sensational image below that supposedly shows the real shape of the Earth is actually a model of the planet’s gravity.

It was created from satellite data and doesn’t show the true shape of our home. Instead, it merely demonstrates the differences in the strength of the Earth’s gravity at different points around it.

It Turns Out That the Solar System Is Not at All Like We Think It Is

It Turns Out That the Solar System Is Not at All Like We Think It Is

The view that the Sun’s rays shine on only one side of the Moon, leaving the other side in permanent darkness, is quite widespread.

This belief results from the fact that our satellite only ever has one side facing the Earth, while the other is impossible to observe from the ground.

But, in fact, the Sun shines and warms both the visible and invisible parts of the Moon.

The truth is that the period the Moon takes to revolve on its axis coincides with the amount of time it takes to orbit the Earth, and this is why we only see one side of it.

It Turns Out That the Solar System Is Not at All Like We Think It Is

It Turns Out That the Solar System Is Not at All Like We Think It Is

Everything seems logical here. Mercury is closest to the Sun, therefore its surface temperature must be higher than all the other planets.

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However, it turns out that the hottest planet in the Solar System is actually Venus, despite the fact it’s 50 million kilometers further away from the Sun than its neighbor.

The average daytime temperature on Mercury is around 350°C, whereas it can reach 480°C on Venus.

The reason for this is Venus’s atmosphere.

Mercury has practically no atmosphere to speak of, whereas Venus has a very thick one made up almost entirely of carbon dioxide.

This creates a very strong greenhouse effect, trapping all the Sun’s heat and making Venus incredibly hot.

It Turns Out That the Solar System Is Not at All Like We Think It Is

It Turns Out That the Solar System Is Not at All Like We Think It Is

Everyone knows that the temperature at the Sun’s surface is unimaginably high: more than 5,700°C. So it’s logical to assume that it’s simply like a giant bonfire. However, this isn’t an accurate comparison. What we think of as fire is in fact energy in the form of heat and light, produced by the thermonuclear reactions occurring in the star’s core.

A thermonuclear reaction involves changing some elements into others, and it’s accompanied by the ejection of heat and light energy. This energy passes through all the layers of the Sun to reach the surface (the photosphere), which to us seems like it’s burning.

The Solar System is not like You think it is [Video]

It Turns Out That the Solar System Is Not at All Like We Think It Is

It Turns Out That the Solar System Is Not at All Like We Think It Is

Everyone who knows a little about astronomy will confidently tell you that the Sun belongs to the category of stars known as yellow dwarves. In turn, it’s logical to assume it is yellow in color.

But, like all other yellow dwarf stars, the Sun is completely white.

So why do human eyes see it as yellow? It’s all down to Earth’s atmosphere. As is well known, light which has a long wavelength, in the yellow and red part of the spectrum, passes through the atmosphere best of all. Light in shorter wavelengths, in the green to violet part of the spectrum (which is what the Sun mainly emits), gets dissipated to a greater degree by the atmosphere.

The effect of this is to make the Sun appear yellow. If you were to leave the atmosphere, the Sun would take on its “true” color

It Turns Out That the Solar System Is Not at All Like We Think It Is

It Turns Out That the Solar System Is Not at All Like We Think It Is

This mistaken view is, of course, the result of various Hollywood movies depicting what would supposedly happen if a person found themselves outside a spaceship.

In reality, our skin is flexible enough to keep all of our internal organs in place. The walls of the blood vessels would also prevent the blood from boiling thanks to their elasticity.

Moreover, in the absence of external pressure in the space environment, the temperature at which blood boils rises to 46°C, which is significantly higher than the temperature of the human body.

http://www.youtube.com/channel/UCv4ZaKnv8JpOt3ljbaZ9s_Q?sub_confirmation=1

https://www.youtube.com/channel/UCF3XAA7OkxeIFMFX3GS7hyg?sub_confirmation=1

Instead, it is the water contained in the cells of our skin that begins to boil in a vacuum. The result is that the human body would expand in size in such an environment, but it definitely wouldn’t explode.

The main reason why a person would die, however, is the lack of oxygen. Just 15 seconds after entering a vacuum without a space suit, the individual would lose consciousness, and they would be dead in two minutes.

It Turns Out That the Solar System Is Not at All Like We Think It Is

The Solar System is not like You think it is [Video]

It Turns Out That the Solar System Is Not at All Like We Think It Is

Here’s one more myth that initially seems logical. If winter is colder than summer, that must mean Earth is further from its source of heat, right?

However, the reality is actually the opposite: during the colder part of the year, our planet is actually five million kilometers closer to the Sun than in summer.

How can this be?

It all comes down to the fact that in addition to orbitting the sun, the Earth also completes rotations around its own axis, which is why we have the change from night to day.

The axis of the planet, which passes through the North and South Poles, is not exactly perpendicular to its orbit and the Sun’s rays which fall on it. In turn, for half of the year a large proportion of the Sun’s warmth falls on the southern hemisphere, while in the other half it falls on the northern one, which produces a change of seasons.

As is well known, summer in the southern hemisphere is warmer than it is in the north.

This is the result of the fact that the Earth comes closest to the Sun in January — that is, when the southern part of the world is experiencing summer.

How special is the solar system?

The history of astronomy has mostly been a one-way journey from a worldview in which our solar system is orderly (and divine) to a view in which we are not special.

Our solar system’s planets, once thought to dance in god-ordained perfect circles in a “music of the spheres,” deviate from circular orbits.

Johannes Kepler, who demonstrated the non-circular orbits of the planets, tried to restore a sense of heavenliness by latching onto a new pattern for their orbits based on Plato’s mathematical solids — but that notion was discredited many years later with the discovery of Uranus.

So when, on a sunny afternoon in California last year, I discovered a set of patterns that seem to rule planetary systems other than our own, I was skeptical.

Were these patterns real, or were they an illusion? And if real, what did they mean about our solar system’s place in the cosmos?

In addition to our solar system, we now know of over 400 multi-planet systems, thanks largely to the Kepler Mission.

Kepler is a NASA spacecraft (named after the 17th century German astronomer) that was launched in 2009 for the sole purpose of discovering exoplanets — worlds orbiting other stars.

It finds those exoplanets by continuously measuring the brightnesses of about 100,000 stars and waiting for the starlight from any of them dim ever so slightly due to the shadow of a planet in transit.

The transit of each planet is unique, allowing the discovery of multiple planets orbiting the same star.

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The pattern I found on that sunny afternoon: planets in the same system tend to be the same size.

For example, if one planet is 1.5 times the radius of Earth, the other planets in the system are very likely to be 1.5 times the radius of Earth, plus or minus a little bit.

This is not at all what my colleagues and I expected. In our solar system, planets range from the size of Mercury (less than half the radius of Earth) to Jupiter (more than ten times the radius of Earth).

The whole population of exoplanets discovered by Kepler ranges from one quarter the size of Earth to about twenty times the size of Earth.

Yet, despite this wide range of possible sizes, planets tend to be about the same sizes as their neighbors. One of my collaborators decided they looked like “peas in a pod,” and that moniker became our shorthand for the pattern.

The Solar System is not like You think it is [Video]

To test whether the peas-in-a-pod pattern was real, I concocted (on my laptop) imaginary planetary systems in which the sizes of planets orbiting a given star were random.

Could some sort of bias in Kepler’s method of finding planets — which favors the detection of large planets close to their stars — contrive to make the planets in each of my imaginary systems appear to fit the pattern?

A representation of the planet sizes and spacings in each of the multi-planet systems with four or more planets from the California Kepler Survey, and our solar system (SOL).

Each row represents a planetary system, with the star at the left (denoted by the Kepler Object-of-Interest name for the system), and planet orbital distance increasing to the right in astronomical units (AU). Credit: Lauren Weiss

The answer was no: in more 1000 trials with randomly assigned planet sizes put through a virtual Kepler’s detection scheme, a pattern of similarly-sized planets in the same systems never emerged.

This computational experiment did not reproduce what we observe in the Kepler planetary systems. Thus, the regular sizes of planets is a real astrophysical pattern.

In addition to having similar sizes, planets in these peas-in-a-pod-like systems also have regular orbital spacing.

We found that the orbital distance between the first pair of planets is a good predictor of the orbital distance of the third planet, and the fourth, and so on. (Regular spacing also exists in our solar system out to Uranus and is called the Titius-Bode Law, but Neptune and Pluto do not follow the pattern).

Furthermore, there is a link between the sizes of the planets and their spacing: the systems with the smallest planet sizes also have the closest orbital spacings.

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What do these patterns mean?

Planet formation is surely governed by the laws of physics, but we do not have a clear narrative of how these laws manifest in the messy environment of planetary birth.

Theories of planet formation were mostly written before the discovery of the first exoplanet; their purpose was to explain the emergence of our own solar system from a disk of gas and dust.

A widely accepted (but unconfirmed) theory about planet formation involves the rise of so-called “oligarchs,” young precursors of planets that each influence a swath of fixed width within the disk around the star.

(Pluto is no longer considered a planet because Pluto was never big enough to be an oligarch.)

Oligarchic theory predicts roughly equal-mass oligarchs spaced at regular intervals, with the size of the oligarch dependent on the width of its influence.

However, because our solar system is not a system of equal-mass planets at regular spacing, the rise of oligarchs is considered a mere chapter in our solar system’s history, an early pattern that was later overwritten by violent impacts that formed our very dissimilar terrestrial planets.

Yet hundreds of exoplanets exhibit a pattern that, in a qualitative sense, resembles our long-lost oligarchs. Perhaps the peas-in-a-pod are aged oligarchs.

If so, how did they evade the violence that later shaped our solar system?

We might find the answer, if we continue measuring the fundamental properties of the peas-in-a-pod planets.

Or we might find additional planets in these systems that break from the pattern, just as the discovery of Uranus deviated from Kepler’s proposed pattern for the orbits in our solar system.

Regardless, I think Kepler would be pleased to see that, thanks to a telescope bearing his name, we have discovered a pattern that pervades not just one, but hundreds of planetary systems.

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