As an example of a sideshow attraction it might have some grotesque appeal, but as an accurate depiction of a human face, it would fail miserably.
Regarding the time-frames involved, it’s true that they’re really immense and hard to grasp, but by reducing the numbers to fractions of a gigayear (as Thangalin did in his timeline post), they become a little more comprehensible.
Thangalin: “At a time when the first single-celled life forms appeared, the Sun was but a deep red fraction of its future self.” He pegs this at about 3.8Gya (billion years ago),
Using his timeline start at 4.654 Gya with the formation of the sun, and basing progress from there on the current theory for evolution of a one-solar-mass G-type main sequence star (that’s our Sun), I’ll add a few other points on the scale:
“4.654Gya – sun formed.” Let’s say that this is the point when the molecular cloud that was condensing to become our sun first began heating up enough to be called a “protostar,” not yet fusing hydrogen as the main source of energy (as it is today), but rather releasing the energy of gravitational contraction as heat. It would glow red because it’s surface temperature would be at about 2000 degrees Kelvin (2000K). It would also still be buried in the dense cloud of its birth, and invisible in the visual wavelengths. Its heat (IR) and microwave emissions could be detected though. Objects like this (called Bok globules) can be found embedded in the visible portions of giant hydrogen clouds – see the very cool Hubble telescope photos of these objects!
4.604Gya – start of “T Tauri phase” of the proto-Sun object. After at most about 50My (50 million years – a long time, but note that it’s only in the second decimal place of the number --short by astronomical standards), gravitational collapse is near its end because the heat & radiation pressure from the proto-Sun is enough to counter gravity’s effects, a condition called hydrostatic equilibrium. Studies show that this happens at around 4000K, giving the object a deep yellow hue. It would still be wreathed in dense tatters of the gas and dust from which it formed, which could also be glowing as well by now, perhaps producing the first visual appearance of a star-like object.
It’s also in this time period that a planetary system would be first be forming from irregularities in the rotating disk of material that the pre-solar nebula has now become – a circumstellar disk. This is thought to happen over a very short timescale compared to other processes, as little as 10My. During this time, the intense solar wind from the proto-Sun would also begin driving off most of the gases and lighter elements from the circumstellar disk, only that captured by what are now the gas giant planets being held back. Dust and heavier materials would continue to accrete into the rocky planets, asteroids, and comets.
By the end of this period, the star would likely be quite visible, and radiating at very close to its main-sequence surface temperature, which for our sun is about 5000K. It may also be significantly larger than our current sun, because it’s still contracting, though much more slowly.
4.504Gya – Beginning of the main-sequence period of the Sun. This marks the beginning of hydrogen fusion in the core of the Sun, ignited by temperatures raised to incredible levels by the further contraction of the solar matter. The size of the new star has stabilized to large degree, and its surface temperature as well. It has “burned off” the last remnants of it’s birth-cloud, only the planets and other rather insignificant debris remaining in evidence. The main-sequence stage of a star’s evolution can last for many billions of years, depending on its mass (high-mass stars burn out faster, low-mass stars last a long, long, long, long, long, long time).
Thangalin places his image in the timeframe of about 3.8Gya. That’s fully 700My after the sun has reached main-sequence by the above timeline. And even if my timescale is too short by fully 100%, it would still mean the sun was its bright, cheery, familiar self by no later than about 4.1Gya. Still 300My before Thangalin’s image.
The point of all this is not to bust chops but to show that for this type of image, presented as Thangalin did, in the context of illustrating a scientific concept, accuracy is extremely important. If he wants to present it as a work of imagination only, fine, he has license to do so as does every artist. But I see a great deal more potential for dramatic images in an accurate approach.
Personally I find the posted image rather bland and much too monochromatic, regardless of its scientific accuracy, or lack of it. The difference in cast-shadow density for the two spherical bodies seems much too great. They both could show more surface detail, having just survived millenia of near-constant bombardment by meteors, asteroids, and comets (and lions and tigers and bears, oh my! ) according to some current theories. Some indication of the division between land and ocean on the Earth would be more interesting. The nighttime sides of both bodies need not be portrayed as a featureless darkness, some shadow detail could be included to make them more interesting.
and iliketosayblah, sorry for the brain-bruise, but as they say, “no pain, no gain.”