In a way the third from a star I am.
I can dramatically change things
for better or for worse.
If spun I am then ineffectual I will be.Higher then me my friend is,
clarify he did in the olden times.
But if we stand together,
closer to ground he will be.
4 Answers
You are
"-" (minus/dash)
Because
In a way the third from a star I am.
On the keyboard, "-" is three keys from "*"
I can dramatically change things for better or for worse.
A minus sign makes a positive a negative, or a negative a positive
If spun I am then ineffectual I will be.
Rotated by 90 degrees (to a vertical bar) and the meaning totally changes.
Higher then me my friend is,
"_" (underscore) is in the upper position on the key
clarify he did in the olden times.
On old typewriters, underscore was used to underline
But if we stand together, closer to ground he will be.
"_-"
-
-
$\begingroup$ Explanation for 4th line: some (most?) people write 1 as a vertical bar, and we know that multiplication/exponentiation by 1 changes nothing. $\endgroup$ Commented Mar 28, 2017 at 14:41
Are you
the letter N
Explanation
In a way the third from a star I am.
Sun is a star and N is the third letter in sun. N represents negative
I can dramatically change things for better or for worse.
Maybe a reference to N (Negative) in medical reports. Sometimes it refers to absence of some disease (Better) and sometimes absence of some required hormones or something (Worse)
If spun I am then ineffectual I will be.
If N is spun in multiple of 180 degrees, it will be the same.
Higher then me my friend is,
Referring to the next letter M
clarify he did in the olden times.
In chats and conversations, 'M..' refers to approval (sometimes to something one did in past)
But if we stand together, closer to ground he will be.
NM represents New Mexico, and is known for the variety of its landscape.
I can't find a reason for most of the clues but.... are you
Earth?
In a way the third from a star I am.
The earth is the 3rd planet from the sun(star).
I can dramatically change things for better or for worse.
If spun I am then ineffectual I will be.
Higher then me my friend is, clarify he did in the olden times.
In olden times it was said that other planets(friends) where up in the sky above us.
But if we stand together, closer to ground he will be.
Earth => ground
-
$\begingroup$ But the earth is the ground, so it can't get closer to the ground $\endgroup$ Commented Mar 28, 2017 at 4:26
are you:
The moon
In a way the third from a star I am.
The moon circles around the earth, which is the third planet from the sun. so in a way the moon is the third from the sun
I can dramatically change things for better or for worse.
tides, which also can lead to very high waves with floading.
If spun I am then ineffectual I will be.
Higher then me my friend is,
seen from the point of the earth the moon is higher up
clarify he did in the olden times.
the moon was a little bit farther from earth long ago
But if we stand together, closer to ground he will be.
if the earth and moon are close together, then the moon is closer to the ground (i.e. earth) we stand on.