Setting value of key in nested object happening incorrectly

Here is an example that you can type in your console. Super new to Javascript. The example of reproducible by opening a new tab and typing it out in a console.

let clothing = ['card0', 'card1', 'card2', 'card3'];
let timers = {}
let timerObj = {"startTime": null, "pauseTime": null, "elapsedTime": null, "hasSubmitted": false} //

for (var i = 0; i < clothing.length; i++) {
  timers[i] = timerObj
  if (i == 0) {
    timers[i]["startTime"] = Date.now();
  } 
} 
console.log(timers) 

What I'm intending to do is, for the 0th index alone, set the timers[0]["startTime"] as Date.now(), and for the rest, let the startTime be null as defined in the timerObj.

Strangely, after running the for loop, I see that for all i, the Date.now() has been set. I understand that Javascript objects are mutable, but why is why are all indices being set to Date.now()?

I looked at other Javascript related Object questions related to a concept call "freezing", not sure I have my basics right.