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The Earth from Space

lpetrich

lpetrich

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The Earth from Space: What did Everybody Think that it Looked Like?

SUNlite3_4.pdf -- the article "So high up the Earth looked like a WHAT?" (PDF page 6) by Martin S. Kottmayer (about UFO contactee and abductee notions of the Earth from outer space)
The Myth of Etana (Article) - Ancient History Encyclopedia
How Artists Once Imagined the Earth Would Look from Space (io9)
Question: Perception of Earth before 1950s. : space
Earth from space in pre-1950's art? : space

MSK tells us the myth of Etana, one of the oldest surviving attempts to imagine what the Earth would look like if one traveled away from it.
Etana was a king of the Sumerian city of Kish, and the fable existed in several versions, probably all the surviving ones were originally part of the library of the Assyrian monarch Ashurbanipal (668-635 B.C.) Joseph Campbell tells one version in writings on myth. The king asks the gods to give him the means to have a child. They direct him to an eagle imprisoned in a pit who knows where there is a plant that will enable this desire to be fulfilled. The bird was in the pit as punishment for breaking an oath once. For his freedom, the bird swore to be servant to any mortal sent to him by Shamash, his god. Etana releases the bird from the pit and they fly to acquire the plant. The bird climbs higher and higher to the heavens. Periodically the eagle asks the king to look below to see how far up they have gone. The journey spans hours and the king reports how he sees the landscape receding with land and sea shrinking and shrinking in apparent size.

They reach the heaven’s gates of Anu, Bel, and Ea, but must continue to a still higher heaven. They climb towards the heaven of Ishtar (our Venus) and below them the king now perceives, “The land is a mere clod and the broad salt sea a wicker basket.” Two hours later, Etana could not even see the land or sea and he cries to the eagle to climb no farther. With that command they start to fall back. It takes hours and when they crash, both shatter. The widow mourns and the king’s ghost is thereafter invoked in times of need.
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Though the Earth is clearly flat in that story, it is correct about the Earth looking smaller and smaller as one goes.

Going to Greece around 800 BCE, when Greece acquired writing again, we find the story of Daedalus and Icarus. But Icarus was over a sea the whole time, and he didn't go far enough up to see much of the Earth.

Advancing forward to 1608 CE, we have Johannes Kepler's  Somnium (novel) ("Dream"). It features a trip to the Moon, and it features the Moon's surface being divided up by the Earth's visibility from it, and also the Earth's phases, though not much more detail about the Earth's appearance.

From io9:
Before this, a number of artists tried to imagine what our planet might look like from space. Most of these simply showed a school globe hanging against a starry background like the Universal Pictures logo. But a few artists made an effort to depict our world realistically.
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Land and sea areas are easy, but clouds are another story.
Some speculated that the earth would appear like a hazy ball, with almost nothing of the surface visible, others that the cloud cover would be intermittent and the atmosphere mostly clear. Even the great Chesley Bonestell was unsure, usually depicting the earth’s clouds in sparse, narrow bands.
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Some of them were fairly realistic, like Camille Flammarion (1884), and Lucien Rudaux (late 1930's) and William Palmstrom (1956) used weather reports. But Howard Russell Butler (1920's), Chesley Bonestell (1950's), and others went the thin-streaks route.

The first picture of the Earth from outer space was taken from a V-2 rocket in 1946 (First Photo From Space | Space | Air & Space Magazine). It went up about 65 mi / 105 km, barely into outer space. So it was until the 1960's, when spacecraft could get much farther from the Earth, far enough to capture its full disk in its field of view. The first full-color one was from the DODGE satellite in 1967: DODGE 1967.


Now to how people might react. MSK notes: "Anyone who followed the space program know that astronauts have sometimes expressed almost mystical transcendent sentiments on seeing the Earth from space." He then noted several of them who had done so. Also, looking at the Earth from space has been a common activity for Space-Shuttle and ISS astronauts. Some science-fiction writers have anticipated it:
George Griffith’s Stories of Other Worlds (1900) has early in it a scene where a traveler perceives the Earth as “infinitely more magnificent” than their destination, the ‘wonderful’ Moon. Griffith has the person “gazing for nearly an hour at this marvelous vision of the home-world which she had left so far behind before she could tear herself away.”
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Then this one from Olaf Stapledon’s Star-Maker (1937):
The spectacle before me was strangely moving. Personal anxiety was blotted out by wonder and admiration; for the sheer beauty of our planet surprised me. It was a huge pearl, set in spangled ebony. It was nacrous, it was opal. No, it was far more lovely than any jewel. Its patterned colouring were more subtle, more ethereal. It displayed the delicacy and brilliance, the intricacy and harmony of a live thing. Strange that in my remoteness I seemed to feel, as never before, the vital presence of Earth as of a creature alive but tranced and obscurely yearning to wake.
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MSK then quotes some UFO contactees, starting with Orfeo Angelucci (The Secret of the Saucers, I think):
The lights inside darkened. Then either the entire craft or the seat turned slightly more to left and the strange window widened about three more feet. I saw a huge globe surrounded by a shimmering rainbow. I trembled as I realized I was actually looking upon a planet from somewhere out in space. The planet itself was of a deep, twilight-blue intensity and the iridescent rainbow surrounding it made it appear like a dream-vision. I couldn’t see it all, for a portion at the bottom of the sphere was cut off by the floor line.

Now I heard a voice that I remembered so well. “Orfeo, you are looking upon Earth – your home! From here, over a thousand miles away in space, it appears as the most beautiful planet in the heavens and a haven of peace and tranquility. But you and Earthly brothers know the true conditions there... My heart was so full of emotion that tears were the only possible expression.”
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MSK quotes some other contactees with similar sorts of descriptions, and then notes some others who weren't very lyrical about the Earth from space. He notes George Adamski and Howard Menger, with the latter describing the Earth as “fast diminishing in size” as he traveled to the Moon.

UFO abductions are a different story. MSK again:
Abductions commonly are about humans being subjected to medical procedures and sexual indignities and aliens have no inherent logical reason to take people off-planet to do such things. Scenes of abductees experiencing space travel are in the minority and seeing the earth shrink into the distance seems quite hard to find even with the help of Bullard’s definitive study of all abduction cases up to 1985.
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He then mentioned 8 cases of abductees seeing the Earth from outer space, and of these 3 cases of the Earth getting smaller and smaller as one goes.

MSK did that to criticize a part of Chris Aubeck and Jacques Vallee’s book Wonders in the Sky: Unexplained Aerial Objects from Antiquity to Modern Times and their Impact on Human Culture, History, and Beliefs (Jeremy P. Tarcher / Penguin, 2010) where they attempted to link the Etana story to UFO-abduction stories.

MSK finds better analogies with UFO-contactee stories, and I agree, though I think that one shouldn't push the parallels very far.

But there is an important parallel, I think. Etana, like those SF-story characters, UFO contactees, and real-life space travelers, was a willing traveler, instead of someone dragged aboard and subjected to clumsy medical examinations and the like.
 
The ancient narration of the view of a smaller planet earth while going away in outer space is based simply on the similar observation when the king left his town and turning his face back, he observed the buildings getting smaller while he was getting away.

On the other hand, the king must have used a telescope when reaching Venus he gave a look to planet earth. If you were around Venus, the view of planet earth should be as "another star in heaven", the same way we see Venus, Mars, Mercury, Saturn, Jupiter... and a more clear image of the planets should be reached solely with the use of telescopes.
 
I'd created two earlier threads:
The Earth from Space -- what did people think it looked like? (2015)
The Earth from Space: What did Everybody Think that it Looked Like? (2017)
I discovered that the 2017 one's OP is essentially a duplicate of the 2015 one. So I'll repost some other discussion.

history of - Earth: Green Planet or Blue Planet? - Science Fiction & Fantasy Stack Exchange
I was reading some older (1930s-era) science fiction and noticed that Earth was described as the "Green Planet". In contrast, modern science fiction uniformly describes it as the "Blue Planet". When and why did this change in terms take place?
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Someone answered that the shift took place in the late 1960's, with the publication of pictures of the Earth taken by some of the Apollo astronauts as they traveled to and from the Moon.

Isaac Asimov's short story "Marooned off Vesta" (Amazing Stories, 1939, "Best of Amazing", 1967) has
He gazed about him. For the first time since the crash he saw the stars, instead of the vision of bloated Vesta which their porthole afforded. Eagerly, he searched the skies for the little green speck that was Earth. It had often amused him that Earth should always be the first object sought for by space-travelers when star-gazing. However, his search was in vain. From where he lay Earth was invisible. It, as well as the Sun, must be hidden behind Vesta.
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But in a 1976 paperback version of a 1973 collection, the phrase became "the little blue-white speck that was Earth".

Likewise, a 1925 story was titled "Earth, the Green Star".

However, there were some pre-Apollo science-fiction stories that had blue as the Earth's overall color, and even some that had yellow as that color.
 
Why green in the first place? I think that it was some noticing all the green vegetation cover.

Why was it mistaken? Our planet's oceans cover 71% of its surface. That produces a big tilt toward ocean color. As to land color, the Sahara Desert and the nearby Arabian Desert are both brighter than nearby vegetated areas.

Simulations of Light Curves from Earth-like Exoplanets - Planetary Habitability Laboratory @ UPR Arecibo has simulations of the inner planets' light curves, and the Sahara Desert is bright enough to make the Earth look whitish rather than bluish, as it does from most directions.


Photos of the Earth from Saturn, Mercury, Mars & Deep Space - Space Facts
A Close-up View of Earth from Mercury and Saturn - Planetary Habitability Laboratory @ UPR Arecibo
Space Images | Bright 'Evening Star' Seen from Mars is Earth

Distances:
Mercury: 0.66 AU (Messenger)
Mars: 0.93 AU (MGS), 1.07 AU (Curiosity)
Saturn: 9.6 AU (Cassini)
"Pale Blue Dot": 40 AU (Voyager 1)
 
Thinking of including one of the earlier threads because of its detail.
 
I'll consider how the age of our planet was determined.
One could start out by asking the oldest person in one's group about what our planet was like, and they'd say that it was just like what it is today in overall outlines. Or one could use what people passed down to each other down the generations, but that often becomes imprecise and only dramatic stuff gets remembered -- and remembered in very mangled form. Thus among Pacific Northwest people, the 1700 earthquake and tsunami were remembered as a fight between a super bird and a whale -- and remembered in different versions. The super bird being big enough to grab the whale with its feet like an eagle grabbing a fish with its feet.

People could sometimes transmit whole epics orally, like the Iliad and the Odyssey, but they had lots of stylization, like being remembered in verse and using stylized phrases like "bright-eyed Athena" and "wine-dark sea". Being in verse form would help to jog its rememberer's memory.

Writing helped greatly in assisting people's memory. Plato in his dialog Phaedrus (360 BCE) imagined someone objecting to writing as making people's memories atrophy and letting people seem more learned than they really are. Plato himself was likely describing objections to writing among his contemporaries, objections that were likely not preserved very much.

But even there, the earliest writers experienced a planet essentially identical to what later generations experienced. So anything before that would be some oral hand-me-down.
 
One of the oldest history books ever is the Sumerian King List, composed about 4,000 years ago in SE Iraq.
"After the kingship descended from heaven, the kingship was in Eridug. In Eridug, Alulim became king; he ruled for 28800 years." His successor ruled for 36,000 years.
  • First dynasty: 5 cities, 8 kings, 241,200 years
  • The Great Flood
  • Kish dynasty 1: 23 kings, 24510 years, 3 months, 3 1/2 days
  • Uruk dynasty 1: 12 kings, 2310 years
  • Ur dynasty 1: 4 kings, 171 years
  • Awan dynasty: 3 kings, 356 years
  • Kish dynasty 2: 8 kings, 3195 years
  • Hamazi dynasty: 1 king, 360 years
  • Uruk dynasty 2: 3 kings, 187 years
  • Ur dynasty 2: 3 kings, 582 years
  • Adab dynasty: 1 king, 90 years
  • Mari dynasty: 6 kings, 136 years
  • Kish dynasty 3: 1 king, 100 years
  • Akshak dynasty: 6 kings, 99 years
  • Kish dynasty 4: 7 kings, 491 years
  • Uruk dynasty 3: 1 king, 25 years
  • Akkad dynasty: 11 kings, 181 years
  • Uruk dynasty 4: 5 kings, 30 years
  • Gutian dynasty: 21 kings, 124 years, 40 days
  • Uruk dynasty 5: 1 king, 427 years
  • Ur dynasty 3: 4 kings, 108 years
  • Isin dynasty: 14 kings, 203 years
Some of the numbers jump around quite a bit among different manuscripts. There is also the problem that some of these kings may have ruled concurrently in different cities instead of ruling sequentially. Also notice how the later reign lengths are much more plausible, about a generation, than earlier ones, especially the pre-Flood ones.

The overall chronology is:
  • Pre-Flood: ~240,000 years
  • The Great Flood
  • Post-Flood: ~7,000 years
 
I first learned of this account in Iosif Shklovskii's and Carl Sagan's book Intelligent Life in the Universe, where they indulge in some ancient-alien speculations. They are *very* cautious about it, however. It's FRAGMENTS OF CHALDÆAN HISTORY, BEROSSUS: FROM ALEXANDER POLYHISTOR.

 Alexander Polyhistor (late Roman Republic),  Berossus (Hellenistic era)

It states that the kings who ruled before the Great Flood ruled for a total of 432,000 years.

Note: "gongre" in that page is a typo for "gongae", a gonga is a certain kind of root used as food. Like potatoes, garlic, onions, carrots, radishes, and turnips.


Turning to Egypt, we find several king lists, including one known to the Graeco-Roman world: Aegyptiaca ("Egyptian stuff") by  Manetho. Its original has not survived, but various copies have survived, like what's collected here: LacusCurtius • Manetho's History of Egypt — Book I

It has a total of about 25,000 years of gods, demigods, and ghosts before the first human king, Menes (about 3000 BCE).

I note that it was Manetho who introduced the word "dynasty" (dunasteia) to denote a sequence of rulers who are related in some way.


Greek mythology presents a rather confused picture, and such philosophers as Aristotle believed that the Universe and the Earth are eternal - infinitely old.
 
Unfortunately, Emperor Constantine made a Christian sect the Roman Empire's official state religion, though old-time religions and belief systems, and also rival Xian sects, survived for a few centuries and were gradually persecuted out of existence.

With Xianity came the belief that the Bible has a lot of literal truth in it, even though some theologians argued away the anthropomorphism of the Biblical God as allegorical. This included the belief that the Universe was created at some time, and the theologian Augustine argued that God created time itself when he started creating the Universe (Augustine on the topic of time).

Augustine wrote a book, The City of God, where he rebutted the remaining pagans' contention that Rome fell because its citizens that turned away from the gods that they had long worshipped. But in CHURCH FATHERS: City of God, Book XVIII (St. Augustine) he has "Chapter 40.— About the Most Mendacious Vanity of the Egyptians, in Which They Ascribe to Their Science an Antiquity of a Hundred Thousand Years." He claims in it that the Universe is less than 6000 years old.


He likely used a method that Xian and Jewish theologians had long used: adding up the dates in the genealogies in the Bible. One has to fill in some of the gaps in that book, and that is why various date estimates vary. Archbishop Ussher's date of creation is one of many. The dates fall into two main categories, depending on which version of the Old Testament / Hebrew Bible / Tanakh that one decides to use.
  • Septuagint (Greek translation): 5,500 BCE
  • Masoretic (Hebrew): 4,000 BCE
Augustine may have used the Septuagint dates. Masoretic users include the creators of the current form of the Jewish calendar (3761 BCE), Archbishop Ussher (4004 BCE), Johannes Kepler (3993 BCE), etc.
 
Getting away from interpreting the Bible required a lot of study of the geological record. Old Earth, Ancient Life: Georges-Louis Leclerc, Comte de Buffon,  Georges-Louis Leclerc, Comte de Buffon

In 1779, he worked from experiments on the cooling of an iron ball to conclude that the Earth is some 75,000 years old. He was made to recant that conclusion by the Faculty of Theology of Sorbonne University in Paris, though these theologians found most of the rest of his work OK.

Back then, the numerous fossil seashells were often considered abundant evidence of Noah's Flood, and Voltaire, deist and critic of the Church, tried to explain them away.
Voltaire argued that fossil shells were either left by the evaporation in dry seasons of freshwater lakes and rivers or re-sulted from a superabundance of land snails which multiplied during wet seasons. If the fossil shells could be shown to be of marine types he explained that they had been dropped from the hats of pilgrims on their way from the Holy Land to their homes, or that the shells had been lost from museums or private collec-tions. If the rock around the fossil was so hard that neither of the above explanations would fit he decided that they were not shells at all, but merely shell-like forms, produced by some oc-cult process of nature in the bowels of the earth
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Fossils: what they mean and how to collect them

But geologists found that the Earth has a much more complicated history than could be explained by any single flood, and by the early 19th cy., Noah's Flood was usually considered to be only one of many geological catastrophes over the Earth's history. It wasn't just the Bible that was evidence for a big flood in the memory of humanity. It was also Greek mythology: Deucalion's Flood. But eventually, such a big flood was completely discredited. Some purported evidence of such a recent flood was in hills of loose rock and dirt found in various places -- moraines. But these hills resemble similar hills produced by glaciers, and they became evidence of huge, continent-sized glaciers. Water in the solid phase, not in the liquid phase.

Some other geologists preferred believing that slow processes occurring over long times was enough - uniformitarians. These are usually considered to have won the debate, and they won big enough for geologists to be reluctant to consider the existence of anything catastrophic much larger than anything that was well-documented. But over the 20th cy., geologists became good enough at their craft to be able to turn catastrophes into well-defined hypotheses.

In the early 20th cy., J Harlen Bretz proposed that the Columbia River Scablands were produced by giant floods. His colleagues seemed almost desperate to refute him. Some decades later, some geologists compared these land features to riverbed features and the like, and they concluded that these were indeed produced by giant floods. The source of this water was also identified: Glacial Lake Missoula, which was dammed by glaciers. Every so often, that glacial dam would break, releasing the lake's water in a huge flood. Something like what's known to happen with mountain lakes and glaciers.

Bigger catastrophes have been identified, like extraterrestrial-rock strikes. Impact craters don't survive very well, but some large ones are known, like the Vredefort Dome (2 billion years old). The origin of the Moon is nowadays attributed to a collision with a Mars-sized planet in the early Solar System. That collision ejected rock fragments that became hot enough to vaporize, and the expansion of this gaseous rock propelled the rock into orbit. That made a ring of bits of solidified rock, a ring that fell on itself to make the Moon. That explains why the Moon is (1) mostly rocky and (2) lacking in volatiles.
 
In the late 19th cy., Lord Kelvin tried to estimate the age of the Earth by considering how long it would take for the Earth to reach its present heat-release rate from an initially molten state. He found 20 to 400 million years. That seemed rather little time for the geologists, with their attempted estimates from sedimentation rates and the like.

But in 1896, Henri Becquerel discovered radioactivity. Radioactive materials could release as much as a million times as much energy per unit mass as could be released by chemical reactions. By 1903, George Darwin and John Joly proposed that if the Earth's interior has enough radioactive material in it, then that could keep it hot for much longer than Lord Kelvin had estimated. Radioactivity also provided a solution for the age problem: radiometric dating.

By the early 20th cy., that technique had revealed that some rocks are at least a billion years old, and the present age champions are:
  • Earth rock formations: 4.0 billlon years (Acasta Gneiss, Slave Craton, N Canada)
  • Earth mineral crystals: a zircon crystal from the Jack Hills, W Australia: 4.4 Gya (those hills themselves are about 3 billion years old)
  • Moon: Lunar sample 15415: 4.46 Gya
  • Mars: meteorite ALH84001: 4.091 Gya
  • Meteorites: 4.5 Gya
  • Meteorite grains: Murchison meteorite: ~ 7 Gya
  • Sun: 4.5 Gya (stellar structure and evolution modeling + helioseismology)
 Oldest dated rocks

So our planet is about 4.5 billion years old.
 
As to the shape of the Earth, the earliest belief about it was that it is flat. But one of the first to clearly state that our planet is roughly spherical is Aristotle, and around 350 BCE, he offered several bits of evidence for that contention.
  • Sphericity is the shape that gets the Earth's materials as close as possible to its center. A rather hand-wavy argument, but it gets the overall idea of hydrostatic equilibrium.
  • The Earth casts a shadow on the Moon when it makes a lunar eclipse, and that shadow is circular no matter where the Moon is in the sky. Thus, the Earth has a circular cross section in all directions, and it is thus spherical.
  • Some stars in the southern sky can be seen in southern latitudes but not northern ones.
The roundness of the Earth was generally accepted ever since in the Western world, at least by educated people.

Nowadays, we have direct evidence, in the form of observations of our planet from outer space.
 
Let us now consider the Earth's interior. At first thought, one might try to go there by traveling to there. Let's see how far one can go.

The maximum known depth of a natural cave is about 2.2 kilometers -- Veryovkina Cave in Abkhazia / Georgia

The maximum depth of a mine is about 4 km -- the TauTona and Mponeng gold mines in Gauteng Province, South Africa

The rocks in those mines reach temperatures of 60 C (TauTona) and 66 C (Mponeng), and the mines must be continuously air conditioned to make them habitable by the miners.

The maximum depth of a drilled hole is 12,262 km - the Kola Superdeep Borehole in Murmansk Oblast, Russia

The end of the borehole has a temperature of 180 C, a temperature which made it difficult to proceed any further.

So one must use indirect methods to proceed any further.

-

The first hint was provided by its magnetism.

Lodestones are permanent-magnet rocks that have been used as compasses for centuries. This implies that the Earth interacts with lodestones in some way, and a common hypothesis was that it has a big mountain of lodestone in the far north.

But in the late 16th cy., a certain William Gilbert got to work with an effect discovered a century before: magnetic dip. A compass tends to point more vertically near a pole than near the equator. After experimenting with lodestones and how they attract each other and attract metal objects, he developed a hypothesis as to what causes this behavior: the Earth's interior is like some giant lodestone.

He decided to test that hypothesis by carving a sphere of lodestone, something he called a "terrella" ("little earth"). He then experimented with compass needles placed near it and he discovered that they are oriented to certain spots on it and that they have magnetic dip.

Thus in agreement with that hypothesis, though the Earth's interior is nowadays thought to be a self-exciting electromagnet. Self-exciting as a result of convection currents in its outer core.
 
I should mention some material brought up from the Earth's interior in approximately pristine state.

Ophiolites are slabs of oceanic crust shoved above continents. They are usually less than 5 km thick, but some of them go up to 8 km thick.

Diamonds are ejected from the mantle in kimberlite pipes. Most of them are formed at depths of 150 - 250 km, though some form as deep as 800 km.

-

I now get to the main method for probing the Earth's interior structure. Propagation of earthquake waves. These waves can go far into our planet's interior, all the way to its center. There are three kinds of earthquake waves:
  • P - primary, pressure, push
  • S - secondary, shear, shake
  • Surface
P and S waves go into our planet's interior. P waves always exist, but S waves only exist in solid materials, and when they exist, they are always slower than P waves.

There is an odd effect called the "shadow zone". Both P and S waves are strong out to 104d from the earthquake epicenter. Then they become very weak, then the P waves become strong again after 140d, but not the S waves.

In 1906, geologist Richard Dixon Oldham published a paper where he showed that this means that the Earth has a liquid core with a composition likely different from its mantle. Its liquid state was evident from the lack of S waves traveling through it, and its different composition with the P waves getting slowed down relative to the nearby mantle. By Snell's law at the mantle-core boundary, this refracts them downward, and that downward refraction then makes the shadow zone.

In 1936, geologist Inge Lehmann discovered that earthquake waves show evidence of a solid inner core.

-

The outer core being liquid means that it can have convection currents, and these currents can interact with electric currents to amplify them, thus making the Earth's magnetic field. That, however, requires an electrically conductive liquid core, so one concludes that it is some liquid metal.
 
As to the composition of the Earth's interior, that is usually inferred with the help of meteorites. Some of them are stony, some of them are iron-nickel, and some of them are mixtures: stony-iron ones. Our planet's mantle's composition can be plausibly inferred from the composition of oceanic crust and the like, and it fits stony meteorites fairly well. Since the Earth's outer core is some liquid metal, it would thus be liquid iron-nickel. Its inner core would be solid iron-nickel. This combination gives the right overall density, especially when one accounts for density increase under compression.

So I end this digression.
 
As to seeing our planet from outer space, I will consider records for what distance we can get from its surface. Either directly, or indirectly, with automated spacecraft.

 Vertical jump
  • Excellent: Men: >70 cm, >28 in, Women: >60 cm, >24 in
  • Average: Men: 41-50 cm, 16-19 in, Women: 31-40 cm, 12-15 in
Not very much. The limit here is from biomechanics: the amount of energy available for a burst of muscle activity. I once saw a diagram of how a kangaroo rat and a horse have the same absolute vertical jump heights, even though a horse is much larger than a k-rat. A k-rat can jump vertically as much as 40 - 50 cm / 16 - 20 in.

Now for the biomechanics. The gravitational-potential equation:
E = m*g*h
for energy E, mass m, acceleration of gravity g, and height h.

Doing some algebra gives us h = (E/m) / g

We find that it depends on (E/m), the energy density, and that is a function of how muscles work.


Climbing a tree can do better.  List of superlative trees - listing height records from 90 to 115 m - 300 to 380 ft. The trees are a mixture of conifers and broadleaf trees. Looking at other species, Wiltshire oak tree declared UK's tallest - BBC News - 40.4m /132.5ft, Wax Palms of Cocora Valley – Salento, Colombia - Atlas Obscura - 60 m / 200 ft


We can do better with artificial structures:  History of the world's tallest buildings and  List of tallest buildings and  List of tallest buildings and structures - a building is defined as having an interior designed for a human presence. Here is a history:
  • Göbekli Tepe, Anatolia (Turkey), ~10000 BCE, 5.5 m / 18 ft
  • Tower of Jericho, Palestine, ~8000 BCE, 8.5 m / 28 ft
  • Anu Ziggurat, Uruk (SE Iraq), ~4000 BCE, 13 m / 40 ft
  • Several Egyptian pyramids
  • Great Pyramid of Egypt, ~2560 BCE, 146 m / 481 ft
  • Lighthouse of Alexandria, ~280 BCE, 100 m / 300 ft (estimate)
  • Pantheon, Rome, ~150 CE, 43.45 m / 143 ft
  • Hagia Sophia, Constantinople (Istanbul), 537 CE, 55 m / 180 ft
  • Hwangnyong Temple, Gyeongju, Korea, 650, 68 - 80 m / 223 - 262 ft
  • Brihadisvara Temple Thanjavur, India, 1010, 66 m / 217 ft
  • Speyer Cathedral, Germany, 1106, 71.3 m / 234 ft
  • Koutoubia Mosque, Marrakesh, Morocco, ~1192, 77 m / 253 ft
  • Lincoln Cathedral, England, 1311, 160 m / 525 ft
  • Several other church towers
  • Washington Monument, DC, 1884, 169 m / 555 ft
  • Home Insurance Building, Chicago, 1885, 42 m / 138 ft
  • Eiffel Tower, Paris, 1889, 300 m / 986 ft
  • Some tall buildings
  • Empire State Building, NYC, 1931, 381 m / 1250 ft
  • Ostankino Tower, Moscow, 1967, 540 m / 1762 ft
  • 1 World Trade Center, NYC, 1971, 417 m / 1368 ft
  • CN Tower, Toronto, 1975, 553 m / 1815 ft
  • Some more tall buildings
  • Burj Khalifa, Dubai, 2007, 829.8 m / 2722 ft

The mechanical limits on jump height also apply to building structure. Here is the stress at the base of a building:

(pressure) = (density) * g * h

giving us h = (pressure) / (density) / g

So a building's maximum height will be limited by the strength of its materials.
 
So it's hard to get above 800 meters in a building.

Going up a mountain would still remain on our planet, but one would be far above any nearby land.

What is the highest point on Earth as measured from Earth's center?
  • Mount Everest's peak is the highest altitude above mean sea level at 29,029 feet [8,848 meters].
  • Mount Chimborazo's peak is the furthest point on Earth from Earth's center. The summit is over 6,800 feet [2,072 meters] farther from Earth's center than Mount Everest's summit.
  • Mauna Kea is the tallest mountain from base to peak at more than 33,500 feet [10,210 meters].
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Mt. Everest thus has the greatest gravitational-potential height.
 
Having taken on solid footing, I now consider how far one can get by using our planet's atmosphere as one's footing.

This has been a subject of some myths and legends, like Etana riding an eagle and Daedalus and Icarus making wings for themselves out of wood and wax and feathers. There are also such legendary super birds as the Native North American thunderbird and the Middle Eastern roc. The latter was a sort of super eagle big enough to carry an elephant with its feet. A roc seems big enough to ride, but I don't know of any story of anyone riding a roc.

But the first successful flight was with a balloon. Balloons work by buoyancy, by their interiors being less dense than the surrounding air.

The first kind of balloon made was a hot air balloon - this kind of balloon lowers density by using heated air.

The first known ones are Chinese "sky lanterns", small paper balloons with small fires in them to heat the air. They go back to at least 200 CE. Recent sky lanterns have been constructed from other materials, like plastic bags. Some of them have been reported as UFOs, something which they technically were. It flew 45 min over 21 km.

The first success in hot-air balloons carrying adult human beings was done by brothers Joseph-Michel and Jacques-Etienne Montgolfier in 1783. To prepare for that, they tested their balloons with various animals. On one occasion, with a sheep, to approximate human physiology, a duck, because it can fly, and a rooster, a bird that cannot fly. That test flight was done with a 35-ft / 11-m balloon, it lasted 8 minutes, extended horizontally 2 mi / 3 km, and had an altitude of 1,500 ft / 460 m. It landed safely. Later that year, a similar balloon flew with two human passengers.

In that year was also an early hydrogen balloon, a rubberized-silk one about 13 ft / 4 m across, designed by Jacques Charles and built by the Robert Brothers. Its hydrogen was made by pouring 1/4 tonne of sulfuric acid onto 1/2 tonne of scrap iron. They soon followed up with a hydrogen balloon with a human crew, JC himself and one of the Robert brothers. Their first flight went to an altitude of 1,800 ft / 550 m, and JC went alone in a second flight, to 10,000 ft / 3,000 m. The first flyers carried with them a barometer and a thermometer, the first scientific instruments ever flown.

 Flight altitude record - balloons have reached impressive height records in our atmosphere. In 1862, Henry Coxwell and James Glaisher reached 11 km / 36 kft in a coal-gas balloon. JG went unconscious from the cold and the low air pressure. By 1957, balloonists had reached 30 km / 100 kft. The maximum to date for a balloonist is 41 km / 136 kft in 2014. The maximum without a balloonist is 53 km / 174 kft in 2002.

Ballooning is limited by the thickness of the atmosphere, and it is not surprising that high-altitude balloons are made of thin plastic. Their lifting gas gradually expands as the balloon rises, stretching out the balloon.

1976 Standard Atmosphere Calculator - plugging in 53 km and no temperature offset gives a temperature of -8 C, a pressure of 0.00051 (1/1950) surface pressure and a density of 0.00056 (1/1800) surface density. That means an expansion of 12 in linear dimensions.
 
But short of that, one can still get impressive high-altitude views, and many people have sent up video cameras in weather balloons and posted those cameras' video online.

I'll now turn to powered flight.

The story of Etana suggests a simple approach: ride some flying animal. But there is a problem. The heaviest present-day flying animals are some birds: the Kori and great bustards, at about 21 kg. It's hard to go much more than that because of the square-cube law -- lift depends on area or size^2, while mass depends on volume or size^3.

Nevertheless, some birds have reached impressive altitudes: there's a case of a vulture that collided with an airplane at 37,000 feet / 11.3 km.

The story of Daedalus and Icarus suggests another approach: build wings for oneself. Over the centuries, many inventors tried that, with very limited success -- at best. But by the late 19th cy., some of them succeeded in building at least halfway functional and reliable ridable gliders. Like  Otto Lilenthal with his hang gliders.

But gliding is very limited. What one wants is powered flight. Around 1900, several inventors worked on doing that, and in 1903, two of them succeeded: Wilbur and Orville Wright. Their airplane did not go very high, only 3 m / 10 ft, but it got off the ground.

By 1910, aviators had reached over 3 km / 10 kft altitude and by 1920, 10 km / 33 kft altitude. By 1938, 17 km / 57 kft, and by 1977, 38 km / 124 kft, counting only aircraft whose propulsion uses air in some way, as reaction mass and/or oxidizer.

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So balloons can reach 53 km and airplanes can reach 38 km. Though the air is very thin at those altitudes, it is still present.
 
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