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When people think about our planetary neighbor, the first thing to come to their heads is Mars. And why should it not? Mars is potentially inhabitable, and there has been some evidence of water on its surface.

Sadly, Venus is like the forgotten middle child. Not the closest to the sun, and not the planet closest to us, Venus is the second closest to the sun and similar to stereotypical middle children, it has been throwing some tantrums.

While it is similar in structure and size to Earth, Venus spins very slowly in the opposite direction, resulting in a day lasting 5,832 hours, or 243 days on Earth (a single day on Venus is actually longer than a year, which is 225 Earth days), in addition to the Sun rising in the West and setting in the East. Its atmosphere is coated with a thick layer of clouds blowing at hurricane force, sending them completely around the planet every five days. Due to the thick and acidic cloud layer, there is an intense greenhouse effect, making Venus the hottest planet in our solar system by far. It can melt lead (about 900 degrees Fahrenheit on its surface), and a glimpse beneath the clouds shows volcanoes and deformed mountains littering the ground.

Earth’s technology does not last very long on Earth’s surface, which means that a human being would probably perish even faster. However, there has been speculation of life existing in one of Venus’ top cloud layers, as the temperatures are more similar to Earth’s in those areas.

But why does this matter? Why is Venus the topic of this week’s post?

The short answer is comparative planetology – the comparison of planets in order to better understand one or both.

Venus, back in the 1920’s was thought of as a sister-planet to Earth. Astronomers and scientists believed it to be a lush planet, ripe for life. However, as time went on, we discovered more and more about Venus. Its atmosphere is 95% carbon dioxide, with the primary component in the clouds being sulfuric acid. Atmospheric lightning continuously flashes through the clouds, which extend up to 100 kilometers above the planet’s surface. The pressure on the surface is the equivalent of feeling like you were 1 mile deep underwater, and I have already addressed the temperature component.

We now know, as just expressed, that Venus is alien to us. The complete opposite of what we assumed it to be, the planet is what many would imagine hell to be like. It would reek of sulfur, with lava channels, massive craters (many meteorites burn up in the atmosphere, so the only craters that could exist/do exist are anywhere from 0.9 to 1.2 miles in diameter), volcanism, and frequent tectonic plate activity. Nothing from Earth could survive there.

Which is why we study it. By understanding why anything on Earth would die on Venus, particularly regarding the atmosphere, allows us to prevent the same result for Earth. Ancient Venus is thought to have had an ocean, possibly more qualities of life we recognize here, but it descended into chaos. Especially studying the runaway greenhouse effect, in addition to the role of aerosols in the atmosphere, and may end up helping us prevent Earth from becoming another Venus.

As of around 10 a.m. on September 26th, 2018, Voyager 1 is about 13,354,442,900 miles from Earth. However, that number increases by at least 200 miles every second, so you may easily add another 100,000 miles by the time you are reading this.

(Voyager 1, as seen on the NASA Eyes on the Solar System App)

The Voyager spacecrafts were launched in 1977, and have now been traveling the cosmos for more than 40 years. Their original missions were to explore Jupiter and Saturn, and after making incredible discoveries regarding active volcanoes on Jupiter’s moons and the intricacies of Saturn’s rings, their missions were extended. Voyager 2 is still the only spacecraft to have visited Uranus and Neptune, and their current Voyager Interstellar Mission (VIM) is to explore the outermost edge of the Sun’s domain and beyond.

In August of 2012, Voyager 1 historically crossed over into interstellar space (the first man-made craft to do so), the region between the stars, filled with materials ejected by the deaths of stars from millions of years ago. Voyager 2 is currently in the “heliosheath”, which is the outermost layer of the heliosphere (the region of space where solar wind has a significant influence) where solar wind is slowed by the pressure of interstellar medium (the matter and radiation that exists in the space between star systems in a galaxy). Both crafts are still sending scientific information about their stellar surroundings back to Earth through the DSN, or the Deep Space Network.

The sciences being analyzed with the Voyager’s instruments are categorized into five teams: Magnetic Field Investigation (MAG), Low Energy Charged Particle Investigation (LECP), Plasma Investigation (PLS), Cosmic Ray Investigation (CRS), and Plasma Wave Investigation (PWS). The science teams are collecting and evaluating data on the strength and orientation of the sun’s magnetic field; the composition, direction, and energy spectra of solar wind particles and interstellar cosmic waves; the distribution of hydrogen within the outer heliosphere; strength of radio emissions that are thought to be originating in the heliopause (the boundary of the heliosphere), beyond which is interstellar space. Due to the length of time that Voyager 1 and 2 have been active, however, there are only four working instruments left on Voyager 1 (the Planetary Radio Astronomy Investigation (PRA) is no longer working), and the Ultraviolet Spectrometer Subsystem (UVS) is no longer working on either craft.

But the favorite part of Voyager 1 and 2 for almost every Earthling is the Golden Record.

(The Golden Record, a time-capsule of human culture and life on Earth)

A sort-of time capsule, the Golden Record aboard Voyagers 1 and 2 are meant to be of benefit for any spacegoers that find them in the distant future. It was started with Pioneer 10 and 11, which carried metal plaques identifying their time and place of origin. However, with Voyagers 1 and 2, NASA was much more ambitious.

The Golden Record contains sounds and images on a copper phonograph disk, intended to display the diversity of life and culture on Earth to extraterrestrials. Selected by a committee headed by Carl Sagan,  it displays 115 images, and includes a variety of natural sounds (such as wind, surf, thunder, birds, whales, and other animals). In addition, they added a 90-minute selection of music, including Eastern and Western classics and a variety of ethnic music, while also incorporating spoken greetings from Earth-people in 55 languages, and printed messages from President Carter and U.N. Secretary General Waldheim.

This Record is a summarization of thousands of years of human history, and often is the topic of discussion when addressing whether anyone thinks extraterrestrials would find us. Sagan once said that “The spacecraft will be encountered and the record played only if there are advanced spacefaring civilizations in interstellar space.”, and it will be around 40,000 years before the Voyagers make a close approach to any other planetary system. “But the launching of this bottle into the cosmic ocean says something very hopeful about life on this planet.”

While the Voyagers may not bring extraterrestrials to us within ours or our great-grandchildren’s lifetimes, it still provides us with incredible information about interstellar composition, and with a hope of one day meeting a civilization that wants to know more than just what was on a record.

“Look, Mommy! A shooting star!”

While we all made wishes like these every once in a while as a kid, what we did not know when we were nine was that what we were seeing were actually just meteors burning up, entering Earth’s atmosphere.

But the real shooting stars are out there. And they are terrifying.

Typically depicted as being massive blue balls of gas, these giants hurtle through space across the milky way and the universe at speeds easily surpassing 1,600,000 miles per hour.

Artist’s depiction from listverse.com.

These hypervelocity stars typically originate from binary star systems that are being drawn into a black hole. As one star in the system is eaten, the other is ejected at incredible speeds, resulting in actual shooting stars.

Most of the stars found travelling within the Milky Way galaxy are coming in, and originally, scientists were stumped as to how they were mostly appearing in the Leo and Sextans constellations. Where did they come from? Why only in those areas?

A study in 2017 used data from the Sloan Digital Sky Survey, in addition to computer simulations, to find out where the stars came from. This revealed that the majority of them have actually been originating from the Large Magellanic Cloud (LMC), the largest and fasted dwarf galaxy orbiting the Milky Way. The LMC travels at around 250 miles per second (900,000 miles per hour), and the binary stars in the system travel around each other at incredible speeds. So if the system breaks up, i.e. one of the stars explode in a supernovae, then the force of the supernova would launch the other star into space as a hypervelocity star. Stars like these are so fast because they travel at the velocity at which they are ejected, plus the speed of the LMC, as that was their original velocity. The fastest stars (or, runaways, as they are called) are launched along the LMC’s orbit towards the Leo and Sextans constellations, explaining the location that these stars are usually found.

As I said, most of these stars are found coming into our galaxy, but what about the ones leaving it?

This graphic from space.com depicts the trajectories of the newly discovered stars that are leaving the galaxy, and where they are in relation to our own sun.

Most stars that are flung from the galaxy are typical hypervelocity stars that are much larger than our own sun, and are launched from the supermassive black hole in the galaxy’s center when their binary system collapses. However, these typical stars have a different composition from 20 sun-size stars discovered in 2014 that were traveling at hypervelocity speeds. This means that these stars did not originate from the galactic core, indicating that there is another, unexpected class of hypervelocity star that relies on an ejection mechanism from the one that holds our galaxy together.

In conclusion, much more research is to be done to discover more about these stars that travel practically faster than we can comprehend. But in the meantime, let’s keep wishing on meteors.

Science Fiction. Whether whether you’re a jedi, a trekkie, or were once very into Doctor Who (I’ve been there), you’ve heard some terms thrown around the various ships that travel throughout the galaxy and across the universe. Specifically, you may have heard of wormholes or portals that transport our heroes across space. Intergalactic shortcuts that allow adventures to happen back to back.

But what if those portals were real?

A study released by NASA in 2012 states that they are, in a way. They are called X-points, or electron diffusion regions, where the magnetic field of Earth connects to the magnetic field of the sun, creating an uninterrupted path from our atmosphere to the atmosphere of the sun. 93 million miles away.

No, you’re not going to make the jump from Earth to Tatooine. But this process of magnetic reconnection is important at our planet, the sun, other planets, and everywhere in the universe by explosively transferring energy from one to the other. Here on Earth, it limits fusion reactors and is the final element controlling geospace weather that affects our modern technological systems. NASA launched a project called MMS that is comprised of four identically instrumented spacecraft that measure plasmas, fields, and particles in order to monitor and witness reconnection.

But the openings in the magnetic fields themselves are incredible. According to NASA’s THEMIS craft and Europe’s cluster probes, they open and close dozens of times every day. Most are small and short-lived, but there are others that are massive and sustained a few thousand kilometers above Earth, where the geomagnetic field meets solar wind. Tons of energetic particles can flow through the openings, heating the upper atmosphere, creating geomagnetic storms, and creating bright polar auroras.

Originally, astronomers did not believe there was any way to predict these phenomena. The portals are invisible, unstable, elusive. Opening and closing without warning, it was not until data from the NASA Polar spacecraft (which orbited Earth, spending a lot of time in its magnetosphere, during the late 1990’s) was examined, showing that the craft encountered many x-points during its mission.

Polar carried many sensors similar to that of the current MMS crafts, and as a result, scientists were able to find five simple combinations of energy particle and magnetic field measurements that tell us when there is an x-point or electron diffusion region.

And so, we now know about these portals that can transfer millions of energy particles, and how to find them. What now?

Scientists are primarily monitoring the reconnections, x-points, and electron diffusion regions in order to better predict effects on Earth technology and weather. But what we all want to know is whether or not we can use them to get somewhere else than the sun. I know that is what I want an answer to.

As of right now, we cannot. The only space highway that we have located that could even theoretically transfer something from Earth would only bring it to the sun’s atmosphere, where the gravitational pull would draw the object in and ultimately destroy it.

But the idea of someday finding a magnetic reconnection between Earth and a distant planet is one that I am sure the astronomers at NASA are entertaining, and hopefully someday we will be able to get from our planet to Pluto in no time at all.