Telescope

Jack grabs the map from the center console.
Michelle says: I know the way.
Wanna drive?
Sure.
He puts the map back, hands her the keys, and the four get in the truck. James joins Michelle in the front and has Dora jump into the footwell at his feet, Annie and Jack take the rear seats. A few moments later, Michelle pulls onto the street in front of the bunker.
James asks her: How far is it?
A decent bit. Used to be about an hour on the highway. If it's in even somewhat decent shape, I'd say we're gonna make it there in about that time.
She turns right at an intersection onto the on-ramp, saying:
Gonna find out very soon...

The pavement is cracked and has potholes, and the highway is partially overgrown. Despite this, its condition is somehow good enough. Michelle floors it and the truck rattles and shakes as it accelerates on the uneven asphalt. James is occupied with calming down Dora for a moment. Eventually, even though she is really too big for that, he takes her on his lap so she can look outside. He looks back up.
Holy shit! How are you not absolutely terrified by this?
Michelle responds: You get used to it... Also, I know very well what I can or can't do with this car – I used to drive the same back then.
He holds onto the handle in the door with one hand while trying to hold Dora with the other.
Michelle glances over at him and adds: Relax, that seat belt is gonna hold you, you gotta hold Dora.

The ruins of the city outskirts fly by. Within a few minutes, they make it out of Ivydale, leaving its valley behind. The mountains make way for an area of plains and shallow hills. The large, rusty signs above still indicate the proximity of Sentinel Shores where they haven't faded completely. Following them, Michelle takes an exit onto another highway that leads north, around the western part of Ivydale's lower side.

After a while, they approach what used to be the outskirts of Sentinel Shores and Michelle takes an exit, getting them onto a rural road. The observatory is located on a hill, now ahead of them – a small group of buildings in the distance. As they get closer, the buildings take distinct shapes. Two of them stand out: The one in the center holds a large geodesic dome and another one, off to the side behind it, is a smooth round dome with a slot cut out of it for a telescope to peek through. Well, it was smooth at one point – now, it has many holes with a tree growing out of the largest one. The geodesic dome is partially covered in vegetation hanging off its outside but looks otherwise intact. The other buildings look like mostly unremarkable ruins in various stages of decay.

Michelle says:
James, I'm sorry, but it doesn't look like you'll be able to look through that telescope – or anyone for that matter...
Aww, what a let-down. Still gonna look for pictures there... Didn't you say you also need a telescope?
There are two telescopes here: That one back there is the optical one, and that ball of triangles in the middle holds a radio telescope. That's essentially just a really big antenna.
An antenna but you call it a telescope?
It works similarly, just for imaging a much lower part of the electromagnetic spectrum. Stars give off a bunch more than just visible light.
I have no idea what you just said but can we try that one?
A lot of things would have to go right for that.

She drives through what remains of an open gate, onto a large, overgrown paved area in between the buildings, going around the radio telescope and parking the truck between it and the optical one. They get out and look around. Trees and bushes grow all over the place, some even out of the buildings' walls. Dora runs up to one of the bushes and barks at it. A young fox jumps out and runs away.
James calls her back: Dora, c'mere!

They start by exploring the optical telescope. The lower part of the building is filled with some technology stuff, preferably not all computers and filing cabinets. Most of their contents are rotting sheets of paper holding documents and logs. Annie finds a folder with photos that are partially stuck together. The ones in the front depicting the outside of the observatory but at least one shows a nebula.
James, look what I found.
Oooh thanks!
He takes it and puts it into a bag. he quickly looks at it, then puts it away

Meanwhile, Jack has found a way upstairs. The stairs have partially collapsed so he drags one of the filing cabinets in their place and climbs to the next floor.
Jack callout

Potential plot hole: Why is the telescope inside a geodesic dome?
Missing: exploring the rest of the optical telescope, not wasting too much time there
Missing: exploring the other telescope