Miramos la luna.

Spanish often drops subject pronouns because the verb ending already shows who is doing the action.

Here, miramos already means we look / we are looking / we looked, so nosotros is not necessary.

You could include nosotros if you want emphasis or contrast:

Nosotros miramos la luna, pero ellos miran las estrellas.
We look at the moon, but they look at the stars.

The ending -amos tells you that the subject is we for the verb mirar.

This is the present-tense pattern for a regular -ar verb:

• miro = I look
• miras = you look
• mira = he/she/it looks
• miramos = we look
• miráis = you all look (Spain)
• miran = they/you plural look

So miramos points to nosotros/nosotras.

Because Spanish mirar normally takes a direct object without a preposition.

English says look at the moon, but Spanish says mirar la luna.

So:

• Miramos la luna = natural Spanish
• Miramos a la luna = not the normal basic structure here

A helpful way to think of it is that mirar behaves more like English watch in its grammar: it goes straight to the thing being watched/looked at.

Spanish often uses the definite article with specific, known things, and the moon is a unique object, so la luna is the normal form.

So:

• la luna = the moon

Leaving out la would sound incomplete or unusual in a basic sentence like this.

By itself, miramos can be either:

• we look / we are looking
• we looked

This is one of those forms where the present and the preterite look the same in writing.

Context tells you which one it is:

• Ahora miramos la luna. = Now we are looking at the moon.
• Anoche miramos la luna. = Last night we looked at the moon.

So the sentence alone is grammatically ambiguous, even if the intended meaning is clear from context.

A common distinction is:

• mirar = to look at, to watch
• ver = to see

So:

• Miramos la luna focuses on the action of looking.
• Vemos la luna focuses on the fact that we can see it.

In real usage, the meanings can overlap a bit, but this is a very useful basic difference.

Yes. The Spanish present tense can often cover both:

• We look at the moon
• We are looking at the moon

If you want to make the ongoing action extra clear, Spanish can use:

Estamos mirando la luna.

That is more explicitly We are looking at the moon.

But Miramos la luna can still express that idea depending on context.

Usually, mirar takes its object directly, with no a, especially when the object is a thing:

• mirar la luna
• mirar el cielo
• mirar la televisión

With people, you may sometimes see a:

• Miramos a Juan.

That is because Spanish often uses the personal a before a specific person.

But with la luna, you normally just say miramos la luna.

No. The verb form miramos only tells you we. It does not show gender.

So it could refer to:

• a group of men
• a group of women
• a mixed group

If you add the pronoun, then you can show gender:

• nosotros miramos la luna = we (masculine or mixed group) look at the moon
• nosotras miramos la luna = we (all-female group) look at the moon