Did Nightmare Moon know about the side effects of the Eternal Night?

[Mywas 687]

So we know Nightmare Moon is made out of Luna's desires to have the ponies love her night. But if everypony died then who can praise her night? She would be even more lonely than before. It doesn't make sense

[An Old Head 4,816]

Eh, probably just a result of her boundless rage clouding her reasoning. At that point, she must have been obsessed with the idea of forcing the population to appreciate the night, and the backlashes from there simply didn't occur to her.

[cuteycindyhoney 13,336]

Why would everypony die? It's a magical realm. How do we know eternal night would freeze them or whatever? I'm sure the Unicorns could provide enough light for crops to grow.

[ShadOBabe 19,027]

Well Luna just wanted some attention, but Nightmare Moon was a separate entity according to both Faust and the comics.

The comics show the Nightmare Forces, a bunch of shadowy creatures that have been living on the dark side of the moon. They wanted to use Luna to bring about eternal night so that could roam around on earth unhindered by the sun. When they pick out your insecurities they can influence you to do what they want.

 

But if you don't follow that, you could just believe that by the time she was Nightmare Moon she had gone mad with power and just didn't think about any consequences. And even if she had eventually figured it out, we'd assume that Celestia would already be dead. Because yeah, NM was straight up trying to murder Celestia in the Season 4 premiere. So she figures it out, and starts to raise the sun and moon again, but she's forever the pony who murdered her sister in a jealous rage. Her subjects would not love her more for this.

[Fhaolan 4,494]

Given the changing expressions we saw during that flashback where Twilight watched Luna's transformation, I would say that she wasn't prepared or expecting it. As such, it's more likely she was running on pure emotion without forethought.

 

Now, as @@cuteycindyhoney says, there's not guarantee that in that world eternal darkness would be as detrimental as it would be here. Physical rules are shown to work quite differently, with manually controlled seasons and the like, so light doesn't necessarily mean heat. And given the base magical nature of the world, plants that thrive off of moonlight isn't that far off of reasonable.

[MLPFanatic34 3,241]

I know this may seem like a dumb question to ask, but in the episode "For Whom the Sweetie Bell Toils", when Luna visits Sweetie Belle and tells her about having a older sister, Luna says "Go see what the future holds if you fail to rein in your worst instincts, as I once did". What did Luna mean by that? The parts where Luna was mentioning Celestia and everything confused me.

[Icedog68 71]

I think that she was so consumed by her desires, that she transformed into nightmare moon, who couldn't care less

[TheChosenPony 279]

Nightmare Moon was a shadow of her former self, the anger kept in the pits of her mind. That wasn't the real Luna, That was Nightmare Moon.