5 Space Missions Under NASA Consideration


From our perspective, missions to other worlds just seem to happen. One day Pluto is a cluster of four pixels; the next day it's a teeming world that looks a lot like Mars. We don't see the decades of research, planning, and engineering that to go into every mission, to say nothing of the travel times, in numbers of years that can reach double digits. NASA periodically puts out calls for low-cost mission proposals, some of which move from PowerPoint to the launch pad. Here are five missions that NASA is presently evaluating. At least one of them will eventually visit other worlds. 


Asteroid 16-Psyche contains about 1 percent of the mass of the asteroid belt, and is basically Cybertron, home planet of the Transformers. There is no water, no minerals conducive to water—it's just a big chunk of iron in space. Scientists suspect that it is the exposed core of a proto-planet whose crust and mantle were blasted away by a series of collisions. Because we're not likely to dig a hole to our own core any time soon, the value in studying such an object is self-evident. If a proposed mission to the asteroid is chosen by NASA, it will be the first time that humans have explored a world that wasn't made of rock or ice.


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You have to admire the effort it took to build the acronym VERITAS, which is short for Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy. VERITAS is a proposed mission to visit Venus and figure out where things went so wrong. Above the clouds, Venus is far more hospitable to humans than Mars. Its temperature and weather aren't all that different from Earth, and scientists have proposed colonizing Venus with a series of airships. Below the clouds, however, Venus is a living hell. With surface temperatures near 900°F, it's hotter than Mercury, and its south pole is consumed by a rapacious, undying superstorm. The questions VERITAS intends to answer involve the state of Venus's geologic activity; its tectonic characteristics in comparison to Earth; and the evidence of past water at its surface.


Venus and Earth are a lot alike. We're about the same size and made roughly of the same stuff. But Venus is a horrible hell sphere and Earth is slightly less bad and teeming with life. What happened? The presence of two Venus missions on NASA's shortlist for consideration speaks to the importance of answering that question. DAVINCI—the Deep Atmosphere Venus Investigations for Noble Gases, Chemistry, and Imaging entry probe—will spend its one-hour descent to Venus analyzing the atmosphere to determine its origin and evolutionary history. It will collect data relating to Venus's long gone ocean, and take the first high-resolution images of tesserae, which are that planet's mysterious highland areas.  


The good news is that NASA has an Office of Planetary Defense. The bad news is that it has nothing to do with space aliens. As the dinosaurs could attest, the solar system is an unforgiving place, and all it could take to turn anthropology into paleontology is a giant rock. NEOCam—short for Near Earth Object Camera—is a four-year mission designed to study asteroids that pose an existential threat to humanity. It is a space-based infrared telescope that will take a hard look at known dangers, and be on the lookout for new ones.


Jupiter shares its orbit with more than 6000 identified asteroids known as Trojans. We're not quite sure where they came from. Maybe they formed around the same time as Jupiter and were simply caught in its gravity. Maybe they were captured early in the solar system's formation, the result of a destabilized Kuiper Belt. Nobody knows! And while the distinction may seem trivial, it's hugely important to understand the history of the solar system. The Lucy mission—named for the 3.2-million-year-old hominid skeleton—will do for the solar system what Lucy the Australopithecus afarensis did for humans, filling in the gaps from the primordial record. The Lucy spacecraft will fly out to Jupiter's Trojan asteroids and scan, image, and map five of them. It's the last-known population of objects in the solar system that is wholly unexplored. 

How Often Is 'Once in a Blue Moon'? Let Neil deGrasse Tyson Explain

From “lit” to “I can’t even,” lots of colloquialisms make no sense. But not all confusing phrases stem from Millennial mouths. Take, for example, “once in a blue moon”—an expression you’ve likely heard uttered by teachers, parents, newscasters, and even scientists. This term is often used to describe a rare phenomenon—but why?

Even StarTalk Radio host Neil deGrasse Tyson doesn’t know for sure. “I have no idea why a blue moon is called a blue moon,” he tells Mashable. “There is nothing blue about it at all.”

A blue moon is the second full moon to appear in a single calendar month. Astronomy dictates that two full moons can technically occur in one month, so long as the first moon rises early in the month and the second appears around the 30th or 31st. This type of phenomenon occurs every couple years or so. So taken literally, “Once in a blue moon” must mean "every few years"—even if the term itself is often used to describe something that’s even more rare.

[h/t Mashable]

Neutron Star Collision Sheds Light on the Strange Matter That Weighs a Billion Tons Per Teaspoon
Two neutron stars collide.
Two neutron stars collide.

Neutron stars are among the many mysteries of the universe scientists are working to unravel. The celestial bodies are incredibly dense, and their dramatic deaths are one of the main sources of the universe’s gold. But beyond that, not much is known about neutron stars, not even their size or what they’re made of. A new stellar collision reported earlier this year may shed light on the physics of these unusual objects.

As Science News reports, the collision of two neutron stars—the remaining cores of massive stars that have collapsed—were observed via light from gravitational waves. When the two small stars crossed paths, they merged to create one large object. The new star collapsed shortly after it formed, but exactly how long it took to perish reveals keys details of its size and makeup.

One thing scientists know about neutron stars is that they’re really, really dense. When stars become too big to support their own mass, they collapse, compressing their electrons and protons together into neutrons. The resulting neutron star fits all that matter into a tight space—scientists estimate that one teaspoon of the stuff inside a neutron star would weigh a billion tons.

This type of matter is impossible to recreate and study on Earth, but scientists have come up with a few theories as to its specific properties. One is that neutron stars are soft and yielding like stellar Play-Doh. Another school of thought posits that the stars are rigid and equipped to stand up to extreme pressure.

According to simulations, a soft neutron star would take less time to collapse than a hard star because they’re smaller. During the recently recorded event, astronomers observed a brief flash of light between the neutron stars’ collision and collapse. This indicates that a new spinning star, held together by the speed of its rotation, existed for a few milliseconds rather than collapsing immediately and vanishing into a black hole. This supports the hard neutron star theory.

Armed with a clearer idea of the star’s composition, scientists can now put constraints on their size range. One group of researchers pegged the smallest possible size for a neutron star with 60 percent more mass than our sun at 13.3 miles across. At the other end of the spectrum, scientists are determining that the biggest neutron stars become smaller rather than larger. In the collision, a larger star would have survived hours or potentially days, supported by its own heft, before collapsing. Its short existence suggests it wasn’t so huge.

Astronomers now know more about neutron stars than ever before, but their mysterious nature is still far from being fully understood. The matter at their core, whether free-floating quarks or subatomic particles made from heavier quarks, could change all of the equations that have been written up to this point. Astronomers will continue to search the skies for clues that demystify the strange objects.

[h/t Science News]


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