Using Date within aggregation framework

Working with Data
, ,
1

I am working on calculating expiry date for each assignment submission date.
I have schema as following

{
  _id: "A01",
   name: "History",
   startDate: "2021-08-26T21:00:00.000Z",
   endDate: "2021-09-29T21:00:00.000Z"
}

It is a trivial example of a document, and I am using aggregation pipeline like the following

{
  $lookup: { // }
},
{
  $addFields: {
      status: { $cond: { if: new Date.getnow() > $startDate && new Date.getnow()  < $endDate, then: "Active", else: "Expired" } }
  }
}

But I have doubts about using such logic, is there any way to achieve using above logic conforming to MongoDB Date query?