A massless particle
the dictionary said
when I first looked it up
back in the '60s
so wonderfully small
they pass right through
our bodies
through the entire planet
as if nothing were there
in fact if all the space
between us and Alpha Centauri
our nearest neighboring star
twenty-five trillion miles away
were filled with water
a neutrino travelling through
would see only a single
water molecule

Then clever scientists
proved there's a tiny mass
less than a millionth
the mass of an electron
yet tiny as they are
there are so many
their mass is more
than all else put together

They come from the Big Bang
from super novae
from stars such as our sun
from nuclear reactors
the sun bombards us
every second sending tens of billions
through every centimeter
of our planet's sunward surface

From Wikipedia I learn
neutrinos have no size
no width, no volume
but have counterparts
anti-neutrinos spinning
in the opposite direction
and that they come
in what the physicists call flavors
each with a slightly different mass
and oscillating change
from one flavor to another
as if a cat could change
into a leopard and then back
moving at speeds so close
to the speed of light
the difference is undetectable

All this suggests to my
non-scientific mind
that this universe
is bent on teasing us
still holding back its secrets
like a lover coyly beckoning
or like a loving parent
encouraging a child to walk
by backing off a bit
while gesturing and smiling
to urge the toddler on