Der Mond unserer Erde - Internet-Vademecum

7.1.5 Der Mond

1 Der Mond unserer Erde
2 de Der Mond hat einen ähnlichen Kern wie die Erde
2 en Moon revealed to have an Earth-like core
3 en What would happen to Earth's Climate and Weather if we had no Moon?
4 de Gezeitenkräfte durch den Mond
5 Videos

⇧ 1 Der Mond unserer Erde
en The moon of our earth
fr La lune de notre terre

Schlotterbeck: Mondphasen
Schlotterbeck: Mondrechner

Night Sky Observer en Moon Page

Spiegel Online de Die faszinierende Landschaft des Mondes
Rekord im Weltall: Vor einem Jahr startete der Lunar Reconnaissance Orbiter (LRO), um den Mond zu erkunden. Tatsächlich fand er dort den kältesten Punkt des Sonnensystems, der je gemessen wurde - und einen verschollenen Mondbesucher. mehr...

⇧ 2 Der Mond hat einen ähnlichen Kern wie die Erde
en Moon revealed to have an Earth-like core

Moon revealed to have an Earth-like core
Mond Kern
868 x 866 Pixel

Klimaskeptiker Info
2011-01-08 de Der Mond hat einen ähnlichen Kern wie die Erde

NZZ Online
2011-01-12 de Der Mond besitzt einen Metallkern

Watts Up With That?
2011-01-08 en Moon revealed to have an Earth-like core

Quelle / Source:

NASA
2011-01-06 en NASA Research Team Reveals Moon Has Earth-Like Core

⇧ 3 en What would happen to Earth's Climate and Weather if we had no Moon?

2018-10-05 en What If We Suddenly Lost The Moon

Watts UP With That? (Antony Watts)
2019-02-15 en What would happen to Earth's Climate and Weather if we had no Moon?

A provocative hypothetical question:

What if the Moon was not there?

This giant rock lights up the night and can even change colors.

So what would we do without it?
Would we all need night vision goggles?
How would it affect the ocean tides? Our seasons?
Or our sleep cycles? Or would the consequences be far more drastic?

As the closest celestial body to our planet, the moon exerts a gravitational pull that governs much of what happens here on Earth Take the sea, for example.

If you like surfing, you can thank the moon when the moon's gravitational pull tugs on our spinning Earth, the oceans respond, giving us high tides in some parts of the world, and low tides elsewhere.

The Earth would speed up it's rotation,

giving us days of six to eight hours long

Rotating at that speed, we would experience

winds up to 480 kms per hour (300 mph).

Birds and insects would have no chance of survival.

Earth''s axial plane would vary by some 10 degrees, causing dramatic shifts in seasons, and

rendering our climate uninhabitable.

Most crops would die with the drastic temperature changes.

We'd experience the worst ice ages known to man, as huge glaciers from the north and south poles would encroach upon the Earth, covering everything except perhaps a small band along the equator.

Inside Science
2015-12-02 en What Would Happen If There Were No Moon?

The moon - it can appear full, shining like a beacon in the night or just a sliver of a nightlight. Still, it's always there.

But what if we didn't have a moon?

Here's the top five things we would miss without it.

Nights would be much, much darker.

The next brightest object in the night sky is Venus - but it still wouldn't be enough to light up the sky - a full moon is nearly two thousand times brighter than Venus is at its brightest.
Without the moon, a day on earth would only last six to twelve hours.

There could be more than a thousand days in one year!

That's because the earth's rotation slows down over time thanks to the gravitational force - or pull of the moon - and without it, days would go by in a blink.
A moonless earth would also change the size of ocean tides - making them about one-third as high as they are now.
Forget about seeing any lunar eclipses - or any solar eclipses - without the moon, there would be nothing to block the sun.
Without a moon the tilt of our earth's axis would vary over time.

This could create some very wild weather.

Right now, thanks to our moon, our axis stays tilted at twenty-three point five degrees.

But without the moon the earth might tilt too far over or hardly tilt at all

leading to no seasons or even extreme seasons.

Without the moon helping to keep the earth on a steady tilt, scientists have even imagined that life on earth may not have evolved the way we know it.

So the next time you look up at the night sky, realize that the moon is making life here on earth shine bright.

EarthSky in EARTH
2017-12-03 en What would Earth be like with no moon?

Earth without its moon would be a very different world indeed.

No eclipses.
Smaller tides.
But the biggest change would be in the length of Earth's day.

Most moons in our solar system are tiny relative to the planets they orbit.

These planets wouldn't miss a moon or two if one got knocked out of orbit.

But Earth's moon is relatively large.

So Earth without its large nearby moon would be a very different world indeed.

Imagine ... no solar or lunar eclipses.

No calendars based on a system of months.

The word month, after all, stems from a word that means moon.

That's because many calendars are based on the changing phases of the moon.

With no moon, there'd be no nearby world for astronauts to visit.

We might never have begun to venture out into the solar system.

The moon and sun together cause the tides.

If we'd never had a moon, we'd still have tides, but they wouldn't be as strong.

What's more, the moon has a place in human culture.

Imagine no romantic moonlight walks - no concept of moon madness, or lunacy.

But the biggest change - for us humans and for other earthly life - would be in the length of Earth's day.

Without a moon, Earth would spin faster.

Our day would be shorter. Why?

It's because, billions of years ago when Earth was young, our planet spun around on its axis much faster.

Our world's cycle of day and night was less than 10 hours long.

The ebb and flow of the tides are what put the brakes on Earth's spin.

So - if you're imagining Earth with no moon - you have to imagine our day on Earth much shorter than our present-day 24 hours.

science.howstuffworks.com / KATE KERSHNER
en What If We Had No Moon?

Astrobiology Magazine / Bernard Foing
2007-10-29 en IF WE HAD NO MOON

The Earth has a large moon, making it unique in the inner solar system.

Mercury and Venus have no moons, and Mars has only two small asteroid-sized objects orbiting it.

In this essay, the father of the SMART-1 lunar mission, Bernard Foing of the European Space Agency, looks at the effect the Moon has had on the Earth, and explores how different our world would be if we had no planetary companion.

Would life have evolved differently, or even appeared on Earth without the Moon?

The moon formation

If the time of Earth's existence was condensed into a 24-hour clock, the moon formation event occurred just 10 minutes after the Earth was born.

The Earth formed 4.56 billion years ago, and the Moon formed about 30 million years later.

At that time, the Earth was a magma ocean.

An impactor about the size of Mars struck the Earth at an oblique angle, and removed some of the magmatic mantle.

This mantle was put in orbit around the Earth, together with some of the debris from the impactor itself, and this material eventually formed the Moon.

When the Moon first formed, it was very close to the Earth.

It was possibly only 20 to 30 thousands of kilometers away, and it would have looked extremely large in the sky, at least 20 to 10 times bigger.

But there were no living creatures on the Earth at that time to witness this beautiful scene.

The effect of the Moon's tidal forcing on the Earth

The tidal effect of a body increases as a cube of the distance, so the effect of the Moon's tidal forcing on the Earth was extremely high at this time, to the point that the early magma ocean was affected.

This provided some additional energy to the heating from radioactive elements present, but after the radiogenic heating decayed, the Moon still was a source of heating that may have had some geological effect, keeping the Earth's magma hot and perhaps forcing additional convection in the Earth's mantle.

After the Earth started to cool,

the first crust started to float on top of the magma.

During this period the Earth was subjected to increased meteor bombardment.

The bombardment had been very intense at the beginning of the solar system and then had started to decline, but about 500 million years after the birth of the Earth, or about 2 hours and 40 minutes into our clock of 24 hours, there was a burst of impactors.

This lasted for about hundred million years, and we call this "the late heavy bombardment."

Many of the large basins on the Moon are evidence of this late heavy bombardment period.

In this way, the Moon is a history book for the inner solar system and the Earth.

We have studied these basins with the SMART-1 mission.

The Earth was hit more often than the Moon,

however, because Earth is larger and has more gravity.

This increased gravity also caused the impactors to be accelerated to higher velocities towards the Earth.

That must have been a catastrophic time to be here.

So many bombardments would have sterilized the planet.

If life had appeared before this period, it would have been extinguished unless it found a way to retreat into niches where it could be protected from these global catastrophes.

When some of these impactors hit the Earth,

the explosion caused rocks and dirt from Earth to shoot up and away from our planet.

Some of that projected material flew all over the solar system, and some of it landed on the Moon.

There could be a few hundred kilograms of Earth material per square kilometer of the Moon's surface, buried under a few meters of lunar soil.

It would be interesting to retrieve those rocks and bring back samples of the early Earth.

Almost nothing from this time period has survived on the Earth because of tectonic recycling of the crust plates or because of atmospheric weathering.

We would try to detect some organics within those rocks, and that could tell us about the history of organic chemistry on Earth.

Some of these rocks could even have preserved fossils of life.

Such rocks could help us look further back into the fossil record, which now stops at 3.5 billion years ago.

This way, we could possibly learn about the emergence of life on Earth.

By exploring the Moon, we also can get clues on how the Earth has evolved.

We can study processes on the Moon that have also shaped the Earth, like volcanism and tectonics.

Because the Moon is smaller than the Earth, the Moon's radiogenic heating dissipated much faster.

After about one billion years, the interior of the Moon didn't evolve much, and surface changes mostly were due to impacts.

There was a brief period of magmatic activity from the subsurface - a few plumes of magma made their way up to the surface and filled newly formed impact basins with basalt, creating what we call the Maria.

This happened up to about 2 billion years ago.

Because the Moon offers different conditions than the Earth, we can better understand how physical processes work generally by studying a larger range of parameters than just the Earth's.

The Moon affects the liquid envelope of the Earth, and the oceanic tides in particular.

The Moon affects the ocean tides more in some areas than others.

For instance, in the channel between the British Isles and the European continent, the tidal range can be 10 meters, compared to what you see in the Pacific, where it is below a meter.

The crust of the Earth is also affected.

The Moon's tidal forcing causes significant heating and dissipation of energy to take place.

Part of this energy is heating the Earth, and part of it is dissipated by forcing the Moon to recede from the Earth over time.

There are people who propose that the tidal effect of the Moon may have helped trigger the convection on the Earth that led to the multi-plate tectonics.

The other planets don't have the same tectonic cycle.

For most of them, the crust is like a lid that doesn't move much horizontally, and the magma and heat are blocked by this lid on the surface.

The Earth instead has rolling convective motion that drags the crust, and then the crust plunges back down into the mantle and gets recycled.

There are some very subtle effects of the Moon in the climate and the oceans.

One pattern that has been found recently is related to the Pacific Ocean's El Niño phenomenon.

You have a cold undersea current coming from the Antarctic sea, and that creates the Humboldt stream which keeps the sea around the South American coast near Peru and Chile quite cold.

Because of this, there are fewer clouds and less precipitation there.

Sometimes this current drifts away from the coast, and then you have much more cloud formation and a period of very bad weather over South America.

Satellites have monitored this stream over the Pacific Ocean and they have found some streams which were not known before.

They can connect some of these streams with how the Moon's tidal effect influences the mixing of the deep ocean.

There was a French-American mission called TOPEX/Poseidon that accurately measured the altitude of the sea and detected a little stream a few centimeters high.

That doesn't seem like a lot, but over the whole area of the Pacific Ocean it represents a huge amount of water transferred from one place to another.

If you would take away the Moon suddenly, it would change the global altitude of the ocean.

Right now there is a distortion which is elongated around the equator, so if we didn't have this effect, suddenly a lot of water would be redistributed toward the polar regions.

The Moon has been a stabilizing factor for the axis of rotation of the Earth.

If you look at Mars, for instance, that planet has wobbled quite dramatically on its axis over time due to the gravitational influence of all the other planets in the solar system.

Because of this obliquity change, the ice that is now at the poles on Mars would sometimes drift to the equator.

But the Earth's moon has helped stabilize our planet so that its axis of rotation stays in the same direction.

For this reason, we had much less climatic change than if the Earth had been alone.

And this has changed the way life evolved on Earth,

allowing for the emergence of more complex multi-cellular organisms compared to a planet where drastic climatic change would allow only small, robust organisms to survive.

The Moon has influenced biology in other ways as well.

For species living near the coast, the tide is an important factor.

When you look at the shorelines, you can recognize different layers of organisms that have adapted to the salt water conditions based on the ebb and flow of the tide.

The eyesight of many mammals is sensitive to moonlight.

The level of adaptation of night vision would be very different without the Moon.

Many of these species have evolved in such a way that their night vision could work in even partial lunar illumination, because that's when they are most active.

But they can be more subjected to predators, too, so there is a balance between your ability to see and your ability not to be seen.

The Moon has completely changed evolution in that aspect.

Human vision is so sensitive that we are almost able to work by the light of the Milky Way.

The full Moon has more light than we need to see at night.

For most of our history, we were hunting and fishing or doing agriculture, and we organized our lives by using the Moon.

It determined the time for hunting, or the time where we could harvest.

That's why most of our calendars are based on the Moon.

Earth-Moon Relationships

In a recent workshop called "Earth-Moon Relationships," psychologists discussed the relation between the lunar phases and several aspects of life.

There was a very interesting correlation, not with the birth of children, but with the time of conception.

Perhaps that is due to some social or sentimental value of the Moon.

We tend to forget the impact the Moon has on our lives because we use electric lights, but for most of our history we had to adapt our behavior to the lunar phases.

Finally, the Moon had a key role in the emergence of science, and in our understanding of our place in the universe.

We saw the repetition of the phenomena of lunar phases, and we observed solar and lunar eclipses.

These were big challenges to our understanding of nature, and a few astronomers were put to death because they weren't able to predict the eclipses.

This challenged us to develop accurate predictions for the motion of the sun and the motion of the Moon.

Studying the Moon helped us determine distances in the solar system and the size of celestial objects.

By studying lunar phases, for example, people were able to determine how far the Moon is from the Earth, the size of the Earth, and our distance from the sun.

More recently, the Moon was the terrain where the space race took place between two political systems, allowing for great technical and scientific achievements.

The Moon has inspired humankind to learn how to travel to space, and to bring life beyond Earth's cradle.

⇧ 4 en Gezeitenkräfte durch den Mond

LEIFIphysik
de Wirkungen der Gezeitenkraft auf die Erde

Unter dem Einfluss der Gezeitenkräfte durch den Mond und auch durch die Sonne kommt es auf der Erde zu einer periodischen Massenbewegung.

Dies hat verschiedene Wirkungen.

Gezeitenwirkung der Meere

Die Gezeitenwirke wird an den Meeresküsten als Ebbe und Flut am deutlichsten.

Sie beträgt ca. 35cm,

schaukelt sich aber an den Küsten bis zu 7m hoch,

in sich verengenden Buchten sogar noch höher.

⇧ 4 Videos

a Wann und wie ist unser Mond entstanden?
b Ebbe & Flut: Was haben die Gezeiten mit dem Mond zu tun?
c Spektrum: Vollständiges Vortragsprogramm
d The Super Moon of May 2012
e Warum zieht der Vollmond die Wolken an?
f Phase of the moon affects amount of rainfall
g So sieht der Mond auf der dunklen Seite aus

↑ a Wann und wie ist unser Mond entstanden?

Spektrum / Video 61
2011-07-11 de Wann und wie ist unser Mond entstanden?

Astronomen wie Prof. Dr. Joachim Krautter von der Landessternwarte Königstuhl sehen im Trabanten der Erde aus gleich mehreren Gründen etwas ganz Besonderes im Sonnensystem.

Vor allem aber fragen sich die Forscher, wie er entstanden ist.

Gemeinsam mit der Erde aus dem protoplanetaren Nebel?

Oder ließ er sich einst gravitativ von ihr einfangen?

Wurde er aus der anfangs schnell rotierenden, flüssigen Erde abgespalten, mit dem Pazifik als noch heute sichtbarer Narbe?

Oder war es doch ein Giant Impact, die Kollision mit einem marsgroßen Protoplaneten, aus welcher der Mond hervorging?

↑ b Ebbe & Flut: Was haben die Gezeiten mit dem Mond zu tun?

Spektrum / Video 47
2011-06-20 de Ebbe & Flut: Was haben die Gezeiten mit dem Mond zu tun?

Zweimal am Tag können wir beobachten, wie das Wasser der Meere sechs Stunden lang ansteigt, um sich gleich darauf sechs Stunden lang wieder zurückzuziehen.

Lange haben sich die größten Astronomen den Kopf über die Gezeiten zerbrochen, recht machten sie den Mond dafür verantwortlich.

Prof. Dr. Christoph Leinert vom Max-Planck-Institut für Astronomie erklärt, welche Rolle der Mond wirklich bei diesem Prozess spielt, warum sich Ebbe und Flut jeden Tag um etwa 45 Minuten verschieben und welche Auswirkungen die Gezeiten auf die Erde haben.

↑ c Spektrum: Vollständiges Vortragsprogramm

Spektrum
de Vollständiges Vortragsprogramm

↑ d The Super Moon of May 2012

Science NASA
en The Super Moon of May 2012

↑ e Warum zieht der Vollmond die Wolken an?

Mond Regen
807 x 705 Pixel

Mond Sonne
721 x 328 Pixel

Erstes Hamburger Klima- und Energiegespräch
2013-06-14 de Warum zieht der Vollmond die Wolken an? Vortrag von Prof. Walter Fett in Hamburg

↑ f Phase of the moon affects amount of rainfall

mond_regen.png
327 x 360 Pixel

Satellite data over the tropics, between 10 degrees S and 10 degrees N, shows a slight dip in rainfall when the moon is directly overhead or underfoot.

The top panel shows the air pressure, the middle shows the rate of change in air pressure, and the bottom shows the rainfall difference from the average.

The change is 0.78 micrometers, or less than one ten thousandth of an inch, per hour.

Die kalte Sonne (Fritz Vahrenholt & Sebastian Lüning)
2016-02-19 de Klimafakten.de und die Deutsche Welle: Eine unheimliche Liaison

Watts Up With That? (Antony Watts)
2016-02-01 en Study claims: Phase of the moon affects amount of rainfall

When the moon is high in the sky, it creates bulges in the planet's atmosphere that creates imperceptible changes in the amount of rain that falls below.

New University of Washington research to be published in Geophysical Research Lettersshows that the lunar forces affect the amount of rain - though very slightly.