Space Just Too Big for Green Lanterns to Patrol, Astronomer Says (SPACE.com)

Seth Robison, Newsarama Contributor
Space.com Seth Robison, Newsarama Contributor
space.com – Fri Jun 17, 2:14 pm ET

The self-appointed intergalactic police force known as the Green Lantern Corps has over 7,200 members, which sounds like a lot, until you learn that their jurisdiction is the entire universe. They are headquartered on the planet Oa, which in the (current) DC Universe resides at the universe’s very center.

Space is, put simply, a very big place, one that might just go on forever, and if that is the case, how can it have a center? Even if it does, can the universe be served and protected by just 7,200 fearless men, women, crystalline entities, ambulatory vegetation and a sentient planet?

"In our current understanding of the cosmos, which is based on Einstein's Theory of General Relativity and subsequent cosmological research, the universe has no center," astronomer Mark Hammergren, of the Adler Planetarium in Chicago, told Newsarama, a sister site to SPACE.com. "Whether or not the universe is finite or infinite in extent, it came into existence at the same time everywhere." [10 Coolest Green Lantern Ring Constructs]

That phenomenon is commonly known as the Big Bang, but it might have been not be what people think, Hammergren continued, "The Big Bang is commonly pictured as a tremendous explosion in space, with matter flying outwards and expanding away from each other. A natural thought is to follow the expansion backwards to find the center of the universe. This is based on an incorrect assumption. Matter and energy did not fly out into preexisting space; space itself came into existence in the Big Bang, and has been expanding since then. So there is no real 'center,' even if the expansion of space conspires to create this illusion. No matter which galaxy you live in, you will see the other galaxies moving away from you, which makes it appear that you are the center of this motion."

Although the current understanding may preclude the notion of a 'universal center' from which the Green Lantern Corps could operate from, it's still not outside the realm of possibility. [Infographic: Science Fiction Superhero – Green Lantern]

For there to be a center, Hammergren explained, the universe would have to be in one of several forms: finite and not curved back on itself, infinite but empty of matter beyond a certain distance or both finite in extent and empty beyond a certain distance regardless of the overall curvature (due to the bending of space by the force of gravity). Although Hammergren warned, "As far as we can currently tell, the universe appears to be much larger than the observable universe and not curved back on itself."

Another concept hampering comic fans from 'finding' Oa and the center of the universe is sheer mathematics.

Hammergren breaks it down: "The universe is not infinitely old; it appears to have formed about 13.7 billion years ago, and light does not travel infinitely fast. Therefore, the farthest objects we can possibly see are those that are close enough to us that their light could have reached us in 13.7 billion years. Anything farther away is too far for their light to have reached us. Because the universe is expanding, those objects that are currently too far from us to be visible will always be too far away to be visible."

Simply, the universe is so big, you could travel in any direction at the speed of light for over a dozen billion years, and you won't find an edge (if there even was one), you'd just be changing your frame of reference. Without being able to see the 'edge' of the universe, we can't use that as a point of reference to trace back to the center.

It gets worse, especially if you are one of the two people assigned to patrol one of the 3,600 sectors into which the leadership of the Green Lantern Corps has divided the universe.

If the universe is just 13.7 billion years old, based on what is possible to be perceived and by using the shape of a cube just to provide a frame of reference, the 'volume' of space that has to be patrolled by just one pair of corps members is about 714.3*10^28 (or 714.3 septillion) cubic light-years in volume. Since a light-year is defined as the distance that an object traveling at the speed of light will cover in a year, a single one is just under 10 trillion kilometers (9.46 × 10^12 km) in length.

Under our current understanding of the universe, having a centrally located base of operations on a planet like Oa is not just impossible, but impractical.

Even if Green Lantern rings were able to transport their bearers at speeds significantly faster than light, the sheer amount of space in each sector would make patrol impossible and hamper response times. The universe is just too big, and no amount of willpower will cover it up.

This story has been provided by Newsarama, a sister site of SPACE.com. Visit Newsarama on Facebook and Twitter.

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Did an Amateur Astronomer Spot a Secret Mars Base? (SPACE.com)

A self-described "armchair astronaut" claims to have identified a human (or alien) base on Mars. David Martines noticed a mysterious rectangular structure that appears to be on the Red Planet's surface while trolling the planetary surface using Google Mars, a new map program created from compiled satellite images of the planet.

"This is a video of something I discovered on Google Mars quite by accident," said Martines, the armchair astronaut, in a now-viral YouTube video. "I call it Bio Station Alpha, because I'm just assuming that something lives in it or has lived in it."

He zooms in the surface anomaly — a long, pixelated, white object — and lists the coordinates as 49'19.73"N 29 33'06.53"W. "It's over 700 feet long and 150 feet wide. It looks like it's a cylinder or made up of cylinders," he says.

Has Martines really found evidence of alien life, or a secret space base, as he and some media sources are claiming? No, say experts: "Bio Station Alpha" is simply a glitch in the image caused by cosmic energy interfering with the camera.

"It looks like a linear streak artifact produced by a cosmic ray," said Alfred McEwen, a planetary geologist at the Lunar and Planetary Lab at the University of Arizona and the director of the Planetary Imaging Research Laboratory. McEwen is the principal investigator of the High Resolution Imaging Science Experiment (HiRISE), a powerful telescope currently orbiting Mars.

Cosmic rays are extremely energetic particles emitted by the sun and other stars. For the most part, the Earth's protective magnetosphere blocks them from hitting the planet's surface, McEwen explained. "But with space images that are taken outside our magnetosphere, such as those taken by orbiting telescopes, it's very common to see these cosmic ray hits. You see them on optical images and a lot of the infrared images too," he told Life's Little Mysteries. [Read: Why Do Photos from Deep Space Take So Long to Get to Earth?]

As a cosmic ray passes through a camera's image sensor, it deposits a large amount of its electric charge in the pixels that it penetrates. If the particle passes through at a shallow angle to the plane of the camera, it affects several pixels along its path. The result is a bright streak on the image.

The digital compression software that converts the image into a JPEG file then "sort of smears out the image, giving it that pixelated look," McEwen said. What started as a clear streak in high-resolution turns into a streak that, in the armchair astronaut's words, looks like it is "made up of cylinders."

McEwen said that the cosmic ray streak would be much easier to recognize in the raw, pre-compressed image, but many orbiters and telescopes have contributed imagery to create the Mars map, and Google doesn't identify the source image.

"I can't tell whether this image was taken by Viking or what," McEwen said. "The people at Google need to document what the heck they're doing. They should be able to identify what the source of their information is, and let people know so they can go back and look at the raw data."

This story was provided by Life's Little Mysteries, a sister site of SPACE.com. Follow Natalie Wolchover on Twitter @nattyover.

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