In 2017, did you catch the solar eclipse, the first video footage of ruby sea dragons and the news about the first asteroid from outside our solar system? Here's a look back at some of the most popular science stories of the past year on CBC News.
Ruby sea dragon
In January, scientists spotted an animal they had never seen before in the wild – a ruby sea dragon. Using a remote underwater camera, they shot some footage of two of the rare seahorse-like marine fish swimming off the coast of southern Australia. Previously, the animal had only ever been known from four dead specimens collected since 1919, and was only recognized as a new species in 2015.
7 Earth-like planets orbiting nearby star
In February, NASA announced the discovery of what looks like the best place so far where life as we know it may exist outside our solar system. Seven Earth-sized planets, all of which could contain water, were found orbiting a small star 39 light-years away called TRAPPIST-1.
Scientists are hoping to use the Hubble Space Telescope and the James Webb Space Telescope, set to launch in 2019, to search the planets' atmospheres for methane, carbon dioxide, oxygen or ozone, which could indicate whether these are truly habitable planets.
First North Americans?
In April, scientists said they had found evidence that humans were in North America more than 100,000 years earlier than previously believed. Stone tools and mastodon bones found in California in 1992 were analyzed using uranium dating and found to have been from 130,000 years ago.
The discovery was controversial, as there had been consensus among paleontologists and anthropologists that humans came to North America about 15,000 years ago.
Ancient baby bird in amber
In June, scientists announced they had found the remains of a prehistoric baby bird preserved in a 99-million-year-old piece of amber in Myanmar, complete with scales, feathers and claws. It even has insects and mites trapped with it.
Canadian scientists say the bird from the Age of Dinosaurs met its untimely end and ended up encased in amber when it was just days or weeks old.
Total solar eclipse
On Aug. 21, a total solar eclipse was visible in the continental U.S. for the first time in 99 years. The "Great American Eclipse" also drew many Canadians south of the border to observe the rare astronomical spectacle.
Many of those who remained in Canada were still treated to a partial solar eclipse.
If you missed the solar eclipse, saw only the partial eclipse and want to experience totality, or saw it and want to relive it, you can check it out here. And you can also start prepping for the next total solar eclipse, which will be visible in some parts of Canada in 2024.
Mysterious signals from space
On Aug. 31, astronomers searching for signs of intelligent life in the universe announced they had detected 15 fast radio bursts from a distant galaxy. The signals were unlike any seen before, prompting one Canadian astronomer to call them "perplexing."
Researchers hope that a new telescope in British Columbia called CHIME, which started running in September, will help solve the mysteries of fast radio bursts.
Twice in 2017, researchers announced they had found the oldest evidence of life on Earth in Canada. In March, an international team of scientists reported that rocks in northern Quebec contained tubular structures of hematite, a type of iron oxide, that were likely made by microbes 3.8 billion years ago.
Then in September, a Japanese-led team said they had found rocks in Labrador that contained graphite that appears to have come from living organisms that lived even earlier — 3.95 billion years ago. That's just over half a billion years after the Earth is thought to have formed, about 4.5 billion years ago.
Colliding neutron stars
In October, for the first time, scientists detected gravitational waves from the collision of two neutron stars, the extremely dense remnants left behind by some supernova explosions. And then, in another first, they spotted the "kilonova" — a star-like brightness in the sky caused by the merging neutron stars, with a telescope.
There were a lot of amazing things about that collision, which produced an amount of gold equivalent to the mass of the planet Jupiter. The discovery was announced less than two weeks after three U.S. scientists won the Nobel Prize in Physics for detecting gravitational waves for the first time in 2015.
Later in October, a Canadian astronomer made another unprecedented discovery. Robert Weryk, now at the University of Hawaii's Institute for Astronomy, spotted an asteroid from beyond our solar system — something that has never been seen before.
The object, later nicknamed Oumuamua (Hawaiian for "scout or messenger from the distant past") was later found to be reddish, rocky, cigar-shaped and about 400-metres long.
Bob McDonald, host of CBC's Quirks & Quarks, noted its resemblance to an alien spaceship in the Arthur C. Clarke novel Rendezvous with Rama. However, scientists who eavesdropped on the asteroid failed to detect any alien signals.
Warning to humanity
In November, more than 15,000 scientists from 184 countries issued a "warning to humanity" that change is needed to save the Earth. They said climate change, forest losses, population growth and unsustainable marine fisheries are all contributing to a mass extinction. Their message reached a wide audience — it was our most-read science story of the year.