Title text: RIP the surface of Mars
| This explanation may be incomplete or incorrect: Created by THE BRILLIANCE OF THE JWST SCARRING THE FACE OF THIS WIKI- Please continue expanding and improving the explanation. Do NOT delete this tag too soon.|
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JWST stands for James Webb Space Telescope, a space telescope launched about 2 weeks prior to publication of the comic. It has a sunshield to protect its instruments from the heat of the sun and to keep them below 40 K (-233 °C/-388 °F). Deployment of the sunshield was completed the day before the comic was published. The JWST has to undergo a complex sequence of deployment steps to unfold parts that had to be packed tightly for launch. This sequence has 344 possible points of failure that would render the very expensive space telescope useless; 75% of them led up to the successful full deployment of the sunshield. Thus successful steps are widely celebrated, with this comic an example of such a celebration.
Ordinary cameras use a flash to take pictures in low-light situations. Outer space is very dark, so this comic posits that the JWST has a very powerful flash to compensate for this. Most astronomical cameras don't use flash photography -- they depend on the light either emitted by objects themselves (e.g., stars) or from nearby very bright objects (e.g., Solar System planets that reflect the Sun's light). A flash generally doesn't work for many reasons:
- It would take too long for the light of the flash to return to the telescope - at least twice the time that it had already taken for the original image to arrive on its own.
- The shutter in this comic operates (with a click) before the flash is emitted, so light from the flash wouldn't even reach the camera's photodetector. It is however possible that the camera is using a time exposure and that the shutter was still open when the flash occurred.
- Not enough 'flash' light would return due to it uselessly spreading in all directions. Instead, in a telescope mirrors and/or lenses focus the light, and long exposure times are used to collect enough of the current light to form a decent image.
- A flash powerful enough to overcome the previous difficulty would have to be inordinately powerful. This would raise significant questions about powering it, and would damage (or at least disturb) many of things the flash would still be able to illuminate.
- The objects and phenomena of interest of JWST are, by dint of their extreme distance, being seen as they were in the early stages of the universe, and emit light that potentially gives vital clues about that era, only marginally this side of the current visible-horizon of our apparently expanding universe. Should our flash ever reach them (assuming they still exist) and we have the patience to await the return (assuming we still exist), this will only reveal the much older versions of whatever they have become and only in the form of light that we have swamped them with.
- Before this, any intervening civilization that possesses (or can still develop) the necessary capabilities will have at the very least responded, if not retaliated, to the original flash. Their response might be far less humorous.
There are some examples of astronomical research done using things similar to a flash. Radar astronomy involves emitting radio waves (microwaves) that bounce off distant planets, asteroids, comets, etc., and analyzing the returned waves. The Lunar Laser Ranging experiment uses lasers, which are loosely related to flashes for photography, to measure the distance between Earth and Moon. The outward light is concentrated upon the approximate area of the lunar target, which employs an optical trick to send most of that which actually struck it back to the approximate area of the source equipment.
The comic assigns the sunshield a new, comical purpose of shielding the Sun and Earth (which is roughly in the same direction as the Sun, due to the deployment at the L2 Lagrange point) from this flash, rather than the other way around. When the camera is taking a picture, the comic shows a totally dark shadow behind the shield.
The comic also has the camera making a "click" sound. In traditional mechanical cameras, this sound comes from the shutter opening and closing, and digital cameras mimic this sound so the user (and subject, when human) knows when the picture is being taken. JWST won't actually click -- it doesn't have a shutter, as it takes long-exposure digital images, and in space no one can hear you click.
The telescope also tells the universe to smile for the picture. The universe doesn't have a mouth to smile with, although there are a number of features on Solar System objects that look like faces; this is a phenomenon called pareidolia. The most well known is the Man in the Moon, but there are numerous others.
The title text suggests that, due to the sunshield not being angled to shield Mars, Mars's surface has been badly scarred by the flash. This implies incredible strength of the flash, perhaps to ensure the light can return from its destinations, comparable to death-ray satellites in fiction.
|This transcript is incomplete. Please help editing it! Thanks.|
- [The James Webb Space Telescope is floating through space, a black background.]
- JWST: Okay, universe-
- JWST: Smile!
- JWST: Click
- [A bright flash glows from the telescope, turning most of the panel white. The left side is blocked and kept dark by the telescope's sunshield.]
- [Caption below the panel:]
- Astronomy fact: The purpose of the JWST sunshield is to protect the Sun and the Earth from the telescope's powerful flash.
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