Fast Radio Bursts (FRBs): FRBs are intense bursts of radio waves which come from distant galaxies and last only a few milliseconds, leaving their origins a mystery yet unexplained.

The Phantom Galaxy: Dragonfly 44, an ultra diffuse galaxy in the Coma Cluster is dubbed as the 'Phantom Galaxy', because its believed to be entirely composed of dark matter.

Fastest star: The S2 star reaches a maximum velocity of 7,000 kilometers per second when it's closest to the Sagittarius A, the supermassive black hole at the center of the Milky Way galaxy. This is about 11 million miles per hour or 1/60th the speed of light.

Baryon asymmetry: Baryon asymmetry, also known as the matter asymmetry problem or the matter–antimatter asymmetry problem, is the observed imbalance in matter and anti-matter.

The 'Great Attractor': A gravitational anomaly in the intergalactic space, the 'great attractor', draws galaxies, including our Milky Way, towards a specific point in space.

Oumuamua: The first confirmed object from another star to visit our solar system, this interstellar interloper appears to be a rocky, cigar-shaped object with a somewhat reddish hue.

The 'Pioneer Anomaly': The unexpected slowing of NASA's Pioneer 10 and 11 spacecraft is dubbed the so-called "Pioneer Anomaly". A recent paper claims that the anomaly was caused by due to the slight, but detectable effect of heat pushing back on the spacecraft.

The Wow! signal: A strong narrowband radio signal detected on August 15, 1977, by Ohio State University's Big Ear radio telescope, then used to support the search for extraterrestrial intelligence.

Mysterious dimming of Tabby's Star: Called KIC 8462852, aka Boyajian's Star; Tabby's Star, has experienced unusual dips in brightness, with NASA's Kepler space telescope even observing dimming of up to 20 percent over a matter of days.

Mars Methane Mystery: NASA's Mars Science Laboratory found traces of methane in the Martian atmosphere in 2009, triggering speculations and discussions about the presence of microbial life on the red planet.