Yes — the Nikon D90 can use a wired timer remote/intervalometer. It connects through the camera’s side accessory connector, which is shared with the GPS interface under the rubber cover, rather than a separate standard remote jack.

That means you are not limited to USB or IR-only solutions. Compatible third-party wired timer remotes made for the D90 are available, and they’re generally the simplest option if you want reliable interval shooting.

IR can also work, but wired intervalometers are usually more convenient for long timelapse sessions because they don’t require line-of-sight to the camera’s receiver.

A DIY IR trigger is another possibility if you’re comfortable building electronics, but for most people a compatible wired timer remote is the easier choice.