Thousands of people tuned in to see the premiere of rare footage of the first submersible dives to Titanic shipwreck at the bottom of the North Atlantic.
The Woods Hole Oceanographic Institution (WHOI) streamed more than an hour of footage taken from the final resting place of the famed passenger ship on YouTube.
It was published on Thursday morning.
Here's what we know about it.
Is this new footage?
No, but most of it hasn't been released for public viewing until now.
It was shot during a deep sea expedition in July 1986.
The footage was captured from cameras on the human-occupied deep sea submersible — think a mini submarine — called Alvin, and a remotely operated deep-sea robot called Jason Junior.
At the time, this was cutting edge underwater technology.
While the wreck was first photographed the year before, the WHOI says the 1986 expedition was "the first time humans set eyes on the ill-fated ship since 1912".
"For WHOI and for the entire ocean research community, Titanic's discovery proved the capabilities of new underwater imaging and navigation systems and helped spur significant advantages in the development of deep-sea exploration technology," a WHOI statement said.
Why is it being released now?
It's coinciding with the 25th anniversary and re-release of James Cameron's 1997 film Titanic in theatres.
"More than a century after the loss of Titanic, the human stories embodied in the great ship continue to resonate," the director said.
"Like many, I was transfixed when Alvin and Jason Junior ventured down to and inside the wreck.
"By releasing this footage, WHOI is helping tell an important part of a story that spans generations and circles the globe."
When did the Titanic sink?
In April, 1912.
It hit an iceberg at about 11.45pm on April 14.
It sank a few hours later at 2.20am April 15.
Where did the Titanic sink?
In the North Atlantic Ocean, more than 600 kilometres from the coast of Canada's Newfoundland.
It was about 2,000 kilometres from its intended destination: New York City.
After many failed attempts to locate it, the Titanic's final resting place was finally discovered on September 1, 1985 by a US and French expedition, which was actually using the wreck as a target to test underwater vehicle prototypes.
How many people died when the Titanic sank?
The exact number is unknown, but it's about 1,500.
According to Britannica, the exact figures are unknown because the original passenger and crew lists had misspellings, omissions and aliases, with suggestions contracted employees on board (such as musicians) weren't properly counted.
The final report from the US inquiry into the disaster said 1,517 people died out of 2,223 people on board.
But figures submitted to the British inquiry into the disaster said 1,490 people died out of 2,201 people on board.
How many people were saved?
Again, the figures vary, but it's about 700.
The US report says 706 people were saved, while the UK report claims 711 people were saved (it tallies that 712 people entered lifeboats, but one person died before the nearby ship Carpathia reached them).
How many lifeboats were on board the Titanic?
There were 20 lifeboats on board, with a combined capacity to carry 1,178 people.
The official list is as follows:
- 14 lifeboats
- 2 emergency boats
- 4 collapsible boats
The UK report said two of those collapsible boats appear to have floated off the ship as it went down, with some people climbing into them from the water.
It said at least eight boats weren't at capacity.
One of them left with only 12 people on board when it could carry 40 people.
Another boat with a capacity of 65 people had just 27 people on board.
The final report of the British inquiry said the under-filling of boats was due to three main reasons:
- Many people didn't realise the danger and didn't "care to leave the ship at first"
- Some boats were lowered with an idea of coming back to the gangway doors to complete loading
- Officers were uncertain of the strength and capacity of the boats