Identificamos un cúmulo estelar.

Identificamos is the 1st person plural form of identificar, so it means we identify or we identified, depending on context.

This is a useful point: for many -ar verbs, the present and preterite forms for nosotros are identical.

So identificamos can be:

• present: we identify
• preterite: we identified

Only the context tells you which one is meant.

Examples:

• Hoy identificamos un cúmulo estelar. = Today we identify / are identifying a star cluster.
• Ayer identificamos un cúmulo estelar. = Yesterday we identified a star cluster.

Spanish often omits subject pronouns because the verb ending already shows who the subject is.

Here, identificamos already tells you the subject is nosotros = we.

So:

• Identificamos un cúmulo estelar.
• Nosotros identificamos un cúmulo estelar.

Both are correct, but the version without nosotros is more natural in many situations.

You would add nosotros mainly for:

• emphasis
• contrast
• clarity

Example:

• Nosotros identificamos el cúmulo, no ellos.
  We identified the cluster, not them.

Because cúmulo is a masculine singular noun.

So it takes:

• un for masculine singular
• una for feminine singular

You say:

• un cúmulo not
• una cúmulo

If it were plural, it would be:

• unos cúmulos estelares

In Spanish, adjectives often come after the noun, especially when they are descriptive or classifying.

So:

• cúmulo estelar = star cluster

This is very normal Spanish word order.

In fact, cúmulo estelar is a standard scientific term. Putting the adjective after the noun sounds natural and expected.

In the singular, estelar has the same form for masculine and feminine.

So you get:

• un cúmulo estelar
• una formación estelar

The plural is:

• estelares

Examples:

• cúmulos estelares
• formaciones estelares

So estelar does not change to estelara or anything like that.

Yes. That is completely normal.

For nosotros forms of regular -ar verbs, the present indicative and preterite often look the same.

Examples:

• Hablamos = we speak / we spoke
• Estudiamos = we study / we studied
• Identificamos = we identify / we identified

Spanish speakers rely on:

• context
• time expressions
• the surrounding sentences

to understand which meaning is intended.

The accent mark shows where the stress goes: CÚ-mu-lo.

Without the accent, Spanish stress rules would make you expect stress elsewhere.

Compare:

• cúmulo → stress on the first syllable
• identificamos → no written accent, because it already follows normal stress rules
• estelar → no written accent, because it also follows normal stress rules

Stress:

• i-den-ti-fi-CA-mos
• CÚ-mu-lo
• es-te-LAR

A simple pronunciation guide is:

ee-den-tee-fee-KAH-mos oon KOO-moo-lo es-teh-LAR

A few notes:

• Identificamos is stressed on -ca-
• cúmulo is stressed on cú-
• estelar is stressed on the last syllable: -lar
• c in cúmulo sounds like k

In standard Peninsular Spanish pronunciation:

• r in estelar is a light tap sound
• vowels are usually pure and short, not diphthongised like they often are in English

Yes, absolutely.

That sentence is grammatically correct:

• Nosotros identificamos un cúmulo estelar.

But in normal Spanish, the subject pronoun is often left out:

• Identificamos un cúmulo estelar.

Including nosotros can sound:

• more emphatic
• more contrastive
• sometimes less natural if no emphasis is needed

Normally, no.

In standard Spanish, a singular countable noun like cúmulo usually needs an article or determiner:

• un cúmulo estelar
• el cúmulo estelar
• este cúmulo estelar

So:

• Identificamos un cúmulo estelar. = normal
• Identificamos cúmulo estelar. = generally not normal standard Spanish

You might see article omission only in very special styles, such as:

• headlines
• labels
• very technical shorthand

But for normal sentence building, keep un.

Yes, it is a common astronomical term meaning star cluster.

Spanish often uses noun + adjective combinations like this in technical vocabulary.

So cúmulo estelar is not just any random combination of words; it is a standard term in astronomy.

You may also see related expressions such as:

• cúmulo abierto = open cluster
• cúmulo globular = globular cluster

Some changes are possible, but the original order is the most natural neutral one.

Normal:

• Identificamos un cúmulo estelar.

You could move things around in special contexts for emphasis, for example:

• Un cúmulo estelar identificamos.

But that sounds marked or literary, not neutral everyday Spanish.

So for a learner, the safest pattern is:

• verb + article + noun + adjective

The infinitive is identificar.

It is a regular -ar verb.

A few present-tense forms are:

• identifico = I identify
• identificas = you identify
• identifica = he/she identifies
• identificamos = we identify
• identificáis = you all identify (Spain)
• identifican = they identify

Since you asked about Spanish from Spain, note the vosotros form:

• identificáis

Yes, this form itself is the same.

The main regional difference in this verb’s present tense is the 2nd person plural:

• Spain: vosotros identificáis
• most of Latin America: ustedes identifican

But identificamos for we is the same everywhere in the Spanish-speaking world.