Beware--Human logic at work above.
The Scriptures state that the "evening and the morning" were the -----day(first through the sixth.
During the "light" portion of the day, vegetation was created and the Sun, moon and stars of this solar system were created during the Day of the next 24 hour period.
No conflict---vegetation still has "night conditions"(and cold) and the vegtation at the artic circle live through the darkest periods,----GOD was aware of what HE was doing in Creation week.
That eighty year old man---Moses---lived another 40 years before he died.
The combinations of the elements into compounds produces heat.
Nothing is impossible to GOD----Matt.19:26, "But Jesus beheld them, and said unto them, With men this is impossible; but with God all things are possible."
Nay....fusion is a crushing of sub atomic particles into heavier elements.
not elements into compounds.
Anyway.....try viewing the event as if you are there.
Genesis is an introduction......God Himself in the face of an old man.
Moses has climbed the mountain.
Not because he was called....but to meet his Maker.
He went up unto the forbidden mountain to die.
He went trespassing on God's mountain not expecting to return.
So.....
Does God have this as an opportunity to bestow unto Moses all they we know as true science?......I think not.
Terms of day and night as we know them?......no.
Consider the terms as brief moments between one formation and another.
We don't accomplish what we do all in one day.
We have brief moments (night) when no work is done.
Saying to Moses the creation in terms we now know as real......would not have worked.
You can't say fusion to Moses and expect him to grasp the notion.
You can't say billions of years for the solar system to form.....he won't get it.
And if he confuses which item came first.....let it slide.
God wasn't talking to a science major.
He was making His own introduction to an old man.
THEN sends that old man back down the mountain as a stammering prophet!
Genesis is read best by people who ARE willing to read between the lines!