Well done here, you've above all captured that nostalgic feel of the night within the soft and flowing prose-like lines of the poem. I love the simplicity of linking the disparate scenes together through a unity of openings, as well as language and tone. Good work all 'round.

There are a couple of methods of expression / pieces of punctuation which I thought could've been tightened a little, as always.

"Somewhere in the world
stars are falling and lovers
are lying in a grass field
watching the steady decent
of a solar system, wishing
on that brilliant death."

I think it'd work better with a comma after "grass field"; there appear to be two separate actions going on there - the lovers are "lying in a grass field," but also the lovers are "watching the steady descent..." Either that, or perhaps change it to "as they watch the steady descent". Speaking of which, I think you meant "descent" (meaning 'moving down' ) rather than "decent" (meaning 'moderately good' ).

"Their palms are whispering
to each other, sharing secrets
tucked deep into their creases
and they are smirking at the sky
tempting the universe, daring her
to scorn their bliss."

Similarly here, I think a comma needs to go after "creases"; you've started an additional-information clause when you put the comma before "sharing", but you haven't closed it. The idea is that if you cut out everything in these commas, the sentence would still make sense - in this case, "Their palms are whispering to each other and they are smirking at the sky..." Also, methinks it'd be better to use "in" rather than "into" here. Just seems to flow better to my eye .

"Somewhere in the world
a man is bent over an infant
two finger pressed delicately
to the soft bones in an
under-developed chest;"

Two fingers. I like this whole stanza other than that, though ^^.

"Somewhere in the world
a musician is on a dim-lit stage
in an under-appreciated bar
singing his soul to the drunks."

Perhaps a comma after the word "bar"; it's extra information ('cos the sentence would make sense without it), so can be separated by a comma.

"They sigh, or grumble, or sit
silently seething with their sins"

Love the sibilance here, very cool .

With regards to the end of the poem, I was a little unsure about the link back to the start with regards to the "endless grass fields". Is this meant to imply that man - the reader, in fact - in the last stanza is the same as the younger boy in the first stanza? If this is so, is the whole poem about the same man, but snap-shotted over time? It seems a little unlikely / unexplained, given that that'd mean he's been a doctor, musician and writer. But if the middle two aren't linked, then it seems an oddity. Maybe it's just me, but I would've liked to see some more hints in the middle two stanzas as to whether or not this is the same person.

Good work!