From evidence of a giant ninth planet lurking in the outer solar system to the invention of reusable rockets, the last10 years have certainly been full of excitement when it comes to space exploration.
1) So as 2020 approaches let's look back at some of the biggest space discoveries breakthroughs and stories during the last 10 years.
2) We marvelled as scientists announced the possible discovery of a 12 mile long underground lake of liquid water below the surface of Mars.
3) We said goodbye to Cassini as it plunged directly into Saturn's violent atmosphere after nearly 20 years of incredible service.
4) We watched as Elon Musk's SpaceX company made history by launching the first-ever commercial spacecraft to resupply the ISS. Accomplishments such as these and many others are helping to improve our understanding of the universe that surrounds us.
5) More than a hundred years ago Albert Einstein predicted the existence of gravitational waves and in October 2015 the US-based Observatory LIGO detected them for the first time. Gravitational waves are ripples in space-time that are caused by violent and energetic processes within the universe. When massive accelerating objects such as black holes orbit each other they disrupt the space-time around them causing invisible waves of distorted space to radiate out at the speed of light, similar to ripples on the surface of a pond. The gravitational distortions detected by LIGO in 2015 originated from the collision of two black holes nearly 1.3 billion light years away and since then they have observed multiple other waves, including those from two colliding neutron stars. LIGOs discovery will help scientists study the universe in a completely new way and will go down as one of humanity's greatest scientific achievements.
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| New Horizons |
6) In July 2015 eight years after its launch NASA's New Horizons became the first spacecraft to visit the distant dwarf planet Pluto. Equipped with an array of instruments New Horizons pointed it cameras spectrometers and other sensors at the mysterious world and revealed Pluto to the earth. It exposed the complexity of its icy uneven surface it's thin hazy atmosphere and it's multiple strange moons. After its flyby was complete New Horizons then went on to a new target a Kuiper belt object that was previously nicknamed Ultima Thule but is now known as Arrakoth. In January 2019 the spacecraft finally arrived at the unusual object while capturing photos that feature a large flat lobe that is connected to a smaller rounder lobe. Arrakoth was the most distant flyby ever attempted however the New Horizons mission has been extended through to 2021 so that the incredible spacecraft can explore another mysterious Kuiper belt object.
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| Black Hole |
7) In April 2019 teen Scientists accomplished what was previously thought to be impossible when they captured the first ever image of a supermassive black hole. The image was obtained by using eight ground-based radio telescopes that were operating together as if they were one massive telescope the size of a planet. The network was called the event horizon telescope and revealed the silhouette of a black hole that is outlined by the glowing gas that surrounds its event horizon the precipice beyond which light cannot escape. The colossal structure is 6.5 billion times more massive than the Sun and is located at the center of the galaxy Messier 87 which is about 54 million light-years away from Earth.
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| Voyager 2 |
8) Although they were launched more than 40 years ago Voyager 1 and 2 are still collecting data and exploring regions where nothing from Earth has flown before. They were originally designed to visit Jupiter and Saturn with an extended mission for Voyager 2 to also fly by Uranus and Neptune. But their mission didn't end there because after the historic encounters were complete the twins continued to explore the outermost edge of the solar system. In August 2012 Voyager 1 became the first spacecraft ever to cross the boundary of the heliosphere the bubble of charged particles that the Sun produces. Then in November 2018 it's twin Voyager 2 also entered interstellar space while capturing groundbreaking data along the way. Both Voyager 1 and 2 have been flying longer than any other spacecraft in history and are still providing humanity with groundbreaking data from a truly uncharted region.
9) For centuries planets beyond our solar system existed only in theory or science-fiction. But in more recent times scientists have successfully developed detection methods that have enabled the discovery of thousands of exoplanets. NASA's Kepler space telescope which is now retired was responsible for discovering about half of the currently confirmed exoplanets. Over the past decade, it revealed rocky world's the size of Earth that may have the right conditions to harbor life as we know it. It found hundreds of super-Earths which are planets bigger than earth but smaller than Neptune and it discovered thousands of gas giants similar to Jupiter or Saturn. Although Kepler is no longer searching the cosmos in 2018 NASA launched a new spacecraft called transiting exoplanet survey satellite or Tess for short that will search every star within 100 light years of Earth. But it seems that we may not have to explore too far away from home to find the next habitable planet because in August 2016 the pale red dot projects confirmed the existence of an exoplanet orbiting within the Goldilocks zone of the red dwarf star Proxima Centuri the closest star to the Sun. The decade also brought us the most detailed study of a comet ever attempted when ESA's Rosetta probe encountered comet 67p churyumov-gerasimenko approximately 372 million miles away from Earth. Comets are considered the primitive building blocks of the solar system and likely helped seed the Earth with water possibly even life. Rosetta arrived at comet 67p in November 2014 where it followed and studied its nucleus its environment and its surface as it drifted towards the inner solar system becoming the first spacecraft ever to orbit and land a probe on a comet. The mission Lander was called Philae and photographed its surface after it unexpectedly bounced twice before ending up in a shadow near a cliff but it did capture part of the comet strange alien landscape. In September 2016 after two years of orbiting the mysterious object Rosetta and the comet was heading towards the outer solar system where the spacecraft would not be able to continue to operate under solar power and so it's made a controlled final plunge into the surface of the comet ending the historic mission.
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| Oumauamua |
10) In October 2017 astronomers observed the first known interstellar object to visit our solar system. The mysterious object was named Oumauamua and was discovered by the University of Hawaii's pan star s1 telescope. Oumauamua was originally classified as a comet however the strange object did not display any comets like traits as it passed by the Sun leading astronomers to second-guess themselves some researchers argued it was an unusually shaped rocky asteroid while others say it's a new type of object altogether or even an alien spaceship. The object appeared to have a rocky cigar-shaped body with a reddish hue and is up to 1/4 of a mile long. Observations of Oumauamua suggest that it had been wandering the Milky Way galaxy for hundreds of millions of years before its chance encounter with our solar system. It was tumbling end over end on a u-shaped hyperbolic orbit that took it around the Sun and back out into interstellar space where we will likely never see it again What an amazing 10 years it's been when it comes to space discoveries and breakthroughs.