On August 18, 2017, a strange object shaped like a cigar was spotted whizzing through our solar system at nearly 60,000 miles per hour. Named ‘Oumuamua, which means “scout” in Hawaiian, this extremely oddly shaped rock looked like something out of a science fiction movie. In fact, some even thought it was an alien spacecraft! Even though we now have more realistic theories about what ‘Oumuamua is, there are still a lot of mysterious things about it.

What in the universe is ‘Oumuamua?

‘Oumuamua is one of the strangest objects we’ve ever seen. Fascinatingly, it’s the first interstellar object to enter our solar system! An interstellar object is just something that came from deep space and that doesn’t orbit around a sun. Here’s a diagram of ‘Oumuamua’s path:

While ‘Oumuamua is long gone by now, scientists are still puzzled as to what it was. Here are some odd and interesting things they observed about ‘Oumuamua:

• It was shaped like a long cigar and estimated to be anywhere from 100 to 1000 meters in length. As it flew through space, it tumbled, like if you threw a spinning ruler in the air!

• When it passed through the solar system, it appeared to be accelerating, or getting faster and faster as it neared the sun.

• Its surface seemed inert, or completely still.

So, what in the universe is this object?

First, before we get into that, let’s review a bit about comets and asteroids.

Comets and asteroids: a quick refresher

Here’s a quick refresher on what comets and asteroids are.

Comets are chunks of ice and dust that orbit the sun. When they get closer, their ice melts, causing the trapped dust to be released and create a glowing coma and tail. This also causes them to accelerate.

Asteroids also orbit the sun, but they are made up of mostly rocks, dust, and metal. They don’t have a coma or tail. In other words, their surfaces are inert.

(If you want to read more in-depth on comets and asteroids, click on the links below!

comets and asteroids to their respective Rocky Visitors