It took me too long to realize that you are probably not talking about something traumatic happening in 2017, but rather about the fact that 2017 was 9 years ago.
However I looked up things that happened in 2017 and these are the things that seemed relevant to me by my arbitrary scale:
- start of Tronald Dumps first presidency including all the stupid shit he did during his first year like withdrawing from the paris climate agreement and UNESCO
- Kim Jong-uns half brother gets assasinated
- the world’s first reflight of an orbital-class rocket
- the last person born in the 19th century dies
- The first observation of a collision of two neutron stars. Both gravitational and electromagnetic waves from the event are detected.
- In the first month of the second phase of the Rohingya genocide starting in August 2017, at least 6700 people are murdered by the Myanmar military.¹
- The Treaty on the Prohibition of Nuclear Weapons is voted for by 122 states.
- Cassini–Huygens ends its 13-year mission by plunging into Saturn, becoming the first spacecraft to enter the planet’s atmosphere.
- Fortnite releases 💀
- Based on the results of a previously held referendum, Catalonia declares independence from Spain, however no one cares², so Catalonia still part of Spain today
- A new species of Orang Utan is identified
- The Zimbabwean Military takes control of the country in a coup d’état
- ʻOumuamua is the first confirmed interstellar object detected passing through the Solar System
¹ the whole genocide has way more deaths (at least 24000), is still ongoing and caused 1,5 Million to flee the country
² it didn’t receive recognition from any country and it produced no legal effect.
i don’t quite see the similarity other than grey pool of water, but thats fine :3