Alineamos la montura del telescopio.

It comes from the verb alinear (to align).

Alineamos is first-person plural: we.
So the subject is we, whether stated or unstated.

It can mean either one.

For -ar verbs, the nosotros form in the present and the preterite is often the same:

• alineamos = we align
• alineamos = we aligned

Spanish relies on context to make the time clear. For example:

• Cada noche alineamos la montura... = Every night we align the mount...
• Ayer alineamos la montura... = Yesterday we aligned the mount...

Because Spanish usually drops subject pronouns when the verb ending already shows who the subject is.

The ending -amos already tells you it is we.

You could say Nosotros alineamos la montura del telescopio, but that usually adds emphasis, contrast, or clarity.

Here, montura means the mount of the telescope: the structure or mechanism that supports and positions it.

In other contexts, montura can also mean things like:

• glasses frames
• a saddle
• a mounting/support

So the word is broader than just astronomy, but in this sentence the telescope meaning is the natural one.

Because de + el always contracts to del.

So:

• de el telescopio → del telescopio

This is a standard Spanish contraction.

Compare:

• la puerta del coche
• el color del libro
• la montura del telescopio

Spanish uses definite articles very naturally in places where English may use a more compact structure.

So Spanish says:

• la montura del telescopio

while English often says:

• the telescope mount

Spanish prefers the structure the mount of the telescope, even though English usually turns that into a noun-noun phrase.

Yes, literally it is of the telescope.

But in natural English, that is usually expressed as:

• the telescope mount
• the telescope’s mount

So the Spanish structure is more analytical, using de, while English often uses either:

• a noun modifier (telescope mount), or
• possession (the telescope’s mount)

Yes, but it would not mean exactly the same thing.

• Alineamos la montura del telescopio focuses specifically on the mount
• Alineamos el telescopio focuses on the telescope as a whole

In real usage, the first version is more precise if the mount is what is being aligned.

Not normally.

Alineamos is usually a statement, not a command. It means either:

• we align
• we aligned

If you want Let’s align the telescope mount, Spanish normally uses:

• Alineemos la montura del telescopio

That is the usual first-person plural command / exhortation form.

That said, in instructional language, Spanish sometimes uses the present as a step in a process:

• Primero encendemos el sistema. Luego alineamos la montura.

That still works more like a procedural statement than a true let’s command.

It is pronounced roughly:

a-li-ne-a-mos

The stress falls on the a before -mos:

a-li-ne-A-mos

There is no written accent because, by normal Spanish stress rules, a word ending in -s is stressed on the penultimate syllable, and that is exactly what happens here.

This is especially useful for Spain Spanish.

• alineamos = we align / we aligned
• alineáis = you all align (vosotros form)

So in Spain, don’t confuse:

• Nosotros alineamos... = We align / aligned...
• Vosotros alineáis... = You all align...

The written accent in alineáis helps distinguish it.