72 New Galaxies Discovered in Hubble Ultra Deep Field
Back in 2004, the Hubble telescope peered into a dark part of the universe in the Fornax constellation just below Orion. After staring at this dark patch of space for nearly two weeks, it delivered an amazing view of the cosmos, packed with galaxies, stars, and planets. Now, astronomers have pointed a spectroscopic telescope at that same point in space resulting in 72 new galaxies discovered, increasing our chance of finding extraterrestrial life.
A Number of New Galaxies Discovered
Originally obtained in the early 2000s, Hubble’s images of a vast array of galaxies was a profound discovery that became known as the Hubble Ultra Deep Field or HUDF. With this data, scientists were able to take a step back in time, much closer to the beginning of the universe when galaxies were originally formed.
Within the HUDF, scientists captured light from 1600 new galaxies, some of which were nearly 13 billion years old.
Some of the galaxies seen in this deep field were different than the typical spiral-armed galaxies we’re accustomed to seeing, like the Milky Way. These galaxies were shaped like bracelet links and toothpicks at a time when the universe was starting to calm down from its initially chaotic phase.
nasa.gov
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Now, astronomers from the European Space Organization (ESO) at Chile’s Very Large Telescope (VLT) have applied a technology known as spectroscopy to the HUDF, in order to see galaxies that are only visible in certain ultraviolet light, known as Lyman-alpha light. Prior to employing spectroscopy, these galaxies were invisible to the Hubble telescope, even though they were perfectly within its frame.
A spectroscopic telescope splits up the light it takes in into an array of individual colors. This allows scientists to glean details about galaxies and stars, such as their distance, age, and the elements they’re composed of. This discovery by the VLT was the most in-depth spectroscopic analysis yet.
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The Potential for Finding Life
The sheer vastness of the universe is practically incomprehensible except when described in what are essentially abstract numbers. The billions of galaxies, containing billions of stars, and subsequently trillions of planets aren’t easy for us to fathom.
Despite the difficulty in wrapping our heads around this quantity, one can at least revel in the fact that we’ve reached the point of being aware of the magnitude of our universe. And the data also provides for a greater opportunity that extraterrestrial life is likely to exist out there.
With the new discovery of 72 previously unknown galaxies, we’re upping that probability significantly. If we consider the estimate that, within the Milky Way alone, there are anywhere between 100 million to 400 million stars, with an average of 8 planets orbiting at a reasonable distance (if we use our solar system), then there are anywhere from 800 billion – 3.2 trillion planets in our galaxy alone.
Take that number and apply it to these 72 new galaxies discovered and there are anywhere from 57 – 230 trillion or more potential planets. This makes the chance that we’re alone in this universe sound pretty unlikely. The question is whether we’ll ever make contact.
In addition to furthering our search for extraterrestrial life, the ESO has employed Chile’s VLT to study dark matter, the enigmatic force that perpetuates the expansion of the universe. This dark matter also makes up about 75 percent of the matter in the universe, theoretically. Scientists have debated about what dark matter could be, classifying it into two types, WIMPs and MACHOs – so clever with their acronyms.
WIMPs are weakly interacting, massive particles, while MACHOs are massive, astrophysical, compact halo objects. WIMPs are more elusive and different from matter as we know it, acting through electromagnetic forces. MACHOs are matter like dead or dying stars, black holes, and neutron stars. These are more familiar matters that aren’t as luminous as other cosmic phenomena of their ilk, therefore they could be nearly invisible to us.
The VLT has imaged these MACHOs in action and believes they are the culprit behind the enigma of dark matter. Sometimes this dark matter is so strong that it can warp the fabric of space-time itself as seen in a recent Hubble picture of a galaxy cluster known as Abell 2537.
What other discoveries might this novel spectroscopic technology provide for us?
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Nemesis Star Theory; Does the Sun Have an Evil Twin?
Many people remain anxious about the threat posed from a hidden nemesis planet, known as Nibiru, that has been prophesied to collide with Earth. Though many of the proposed dates for this collision have come and gone, there is another celestial body that may be more likely to lead to an apocalyptic event: The Nemesis Star.
The Nemesis Star TheoryÂ
Binary star systems occur frequently and are actually more common than single stars. At least that’s what we thought, until a recent hypothesis proposed the possibility that every star starts out as a binary pair or multi-pair system. While the theory hasn’t been confirmed, there is significant evidence that our Sun likely has a twin, an evil twin.
The majority of stars in the galaxy are red dwarfs, which are a fifth of the size of the sun and up to 50 times fainter. These types of stars are pretty commonly paired with another star in a binary system, leading astronomers to believe that Nemesis would be the Sun’s red dwarf star companion. But due to the small size and faintness of these stars, they can be hard to find, making Nemesis all the more elusive.
binary stars courtesy wired.com
This star is thought to be responsible for 12 cyclical extinction events on Earth, including the one that killed the dinosaurs. The Nemesis Star Theory’s roots can be traced to two paleontologists, David Raup and Jack Sepkoski, who noticed that there was a periodicity to major die-outs throughout Earth’s history, occurring in 26 million year intervals. This led to a number of astrophysicists and astronomers, postulating their own Nemesis Star hypotheses.
So how would the sun’s twin be responsible for mass extinctions? The Nemesis Star Theory proposed the idea that the Earth’s binary twin must be in a large 1.5 light-year orbit, retaining just enough gravitational pull between it and the Sun so as not to drift off. But the issue with the orbit of Nemesis is the possibility that it occasionally passes through a cloud of icy debris on the fringe of our solar system, known as the Oort Cloud.
Don’t Perturb the Oort
The Oort Cloud is a theoretical sphere that is believed to orbit our solar system, consisting of planetesimals, the small icy building blocks of planets, comets, and asteroids. These planetesimals are sticky and collide with each other until they become large enough to have a significant gravitational pull, eventually becoming as large as a moon or a planet. They also create asteroids and comets which can be knocked out of orbit and sent hurtling toward the center of the solar system, crashing into planets.
There is a binary star system that once passed close enough to nearly perturb the Oort, and it was likely visible from Earth. Scholz’s Star made a flyby some 70,000 years ago, at a distance of 50,000 astronomical units (AU), with one AU being the distance from Earth to the Sun. The Oort is thought to extend from anywhere between 5,000 and 100,000 AUs and is believed to contain up to two trillion celestial objects. Astronomers are 95% certain that Shulz’s star passed within half of a light-year of us, possibly perturbing the Oort, though apparently not enough to cause a mass extinction event.
Comets are believed to exist within the Oort and are the product of a thief model, a give-and-take of celestial bodies between stars when they’re formed. In this process, comets get pulled back and forth between the gravitational field of stars. It was for this reason that the Oort was theorized, due to the number of comets coming from it, there had to have been a sibling star that pulled them out to the Oort.
The Oort courtesy of space-facts.com
Astronomers also found a dwarf planet in the Kuiper Belt, a region just before the Oort that also contains icy, celestial bodies. This planet, named Sedna, orbits the Sun in a long, drawn-out elliptical path and is one of potentially hundreds. Sedna may help to explain the Nemesis star theory, in that its far-flung orbit was likely caused by our Sun’s twin, pulling it out as it drifted off into the depths of space. Imagine if instead of 9 planets in our solar system, there were a few hundred?
So where is this Nemesis star? Several years ago, the E.U. launched the wonderfully named, Gaia satellite, to map out the stars in the Milky Way and look specifically at stars that have had a close encounter with our solar system or that might come close in the future. But whether or not Nemesis will be found is unknown; it’s possible that it could make a return for the next mass extinction, or it is possible that it drifted off, perturbing the Oort of another star.
