【Jelena Jensen Archives】

Even though 2017 sometimes felt like a slow descent into madness,Jelena Jensen Archives some truly amazing things happened this year as well.

But not all of them were on Earth.

SEE ALSO: Google released some fascinating data about the coming total eclipse

From a total solar eclipse to an interstellar asteroid, space news was filled with incredible stories in 2017.

Here are our top-5 favorites:

A total solar eclipse darkened skies across the U.S.

The total solar eclipse, which crossed the U.S. from coast to coast on August 21, was definitely a highlight of the year for the millions of people lucky enough to see it.

It was a communal event that everyone could get behind.

People traveled from around the world to experience minutes of totality, watching the sky get darker and darker over the course of hours as the moon passed in front of the star's face.

In the line of totality, which cut a line from Oregon to South Carolina, people were able to see up to four planets during totality, a sight not available during daylight.

And hey, if nothing else, the total solar eclipse brought the concept of "solar eclipse" glasses to thousands, if not millions, of people across the U.S... except for maybe President Donald Trump.

Now we know where Earth's gold came from

Via Giphy

Billions of years ago, in deep space, two super-dense neutron stars collided, and in 2017, the echoes of that extreme merger arrived at Earth.

The collision of the neutron stars -- which are remnants of long-dead, massive stars -- was felt by the LIGO observatory, two identical L-shaped detectors in Louisiana and Washington.

The detectors felt the minute ripples in space and time created when the two stellar remnants crashed into each other, literally warping the fabric of space-time around them.

As soon as scientists observed those ripples and figured out that they were from neutron stars, not black holes, a cosmic mystery was solved.

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That neutron star collision created billions of tons of gold and other heavy elements, confirming something long-suspected by scientists: That the gold on Earth was delivered to the planet by the mergers of neutron stars.

The death of a beloved spacecraft

Original image has been replaced. Credit: Mashable

In September, the Cassini mission came to its fiery end.

The long-lived spacecraft at Saturn fell into the ringed planet's atmosphere in a planned dive that ended its mission, saving the planet's watery moons from possible contamination.

During the course of 10 years, Cassini completely transformed our understanding of Saturn and its dozens of moons. The spacecraft revealed never-before-seen parts of the planet's rings and large and small natural satellites.

For scientists and space fans on Earth, the end of Cassini was bittersweet.

Now that the mission has ended, our close-up eye on Saturn has shut, without another one ready to open.

While future missions may fly to Saturn and its moons, NASA has nothing on the books for another mission in the near future.

SpaceX sticks its 20th successful rocket landing

Original image has been replaced. Credit: Mashable

Elon Musk's private spaceflight company has done some impressive things this year.

From flying to the International Space Station multiple times to launching more times this year than any year before, SpaceX has pretty much been killing it since an accident in 2016 set them back.

But perhaps best of all is the fact that the company managed to successfully perform is 20th rocket landing.

SpaceX capped off its year with its 20th landing on Dec. 15, bringing its dreams of creating a fleet of relatively cheap, reusable rockets closer to reality.

That reusability, in theory, could be key to reducing the cost for anyone to fly to space, allowing more people and nations to have access to orbit and beyond.

Keep an eye out for the company in 2017 as well. SpaceX is set to fly the maiden flight of its Falcon Heavy rocket on a test trip, sending a car (yes, really) out to a far-off orbit around Mars.

Astronomers find their first interstellar asteroid

For the first time in history, astronomers discovered an interstellar asteroid flying through our solar system.

The asteroid -- now named ‘Oumuamua -- was discovered by a group of scientists in Hawaii, and they quickly realized that they had something special on their hands.

‘Oumuamua was on a trajectory that clearly brought it into the solar system from some other far-off point in our galaxy. Astronomers quickly gathered data about the distant space rock, figuring out that it's probably long and skinny, unlike anything we've seen in our solar system so far.

It's also probably not alone.

Scientists estimate that about one interstellar object like this enters our solar system each year.

Some excited researchers also listened in on ‘Oumuamua to see if maybe it was emitting any radio signals implanted into it by some intelligent alien civilization that sent it out into the universe on their behalf.

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The most epic images from the 2017 total solar eclipse

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