a. >> one, two, three -- >> we're not crazy! >> and elton gone? what legendary singer elton john told us about his upcoming retirement. >> what is it that you want to leave with people as you exit the stage? >> but first, the nightline file -- hey hun. look at all this extra room i have on this king size ikea bed. are you wearing a... duvet cover? why yes. yes i am. where's mom? we finally redid our bedroom and she's prettttttttttty into it. what's your dream? at ikea, we help you live it. make the dream yours. hey hun. look at all this extra room i have on this king size ikea bed. are you wearing a... duvet cover? why yes. yes i am. where's mom? we finally redid our bedroom and she's prettttttttttty into it. what's your dream? at ikea, we help you live it. make the dream yours. >> good evening. tonight, an emotional victory for more than 100 young women who joined forces against the man they say sexually abused them back when many of them were just little girls. the chairs in the courtroom signaling another bold step forward for women in this historic me too moment as the judge effectively condemned him to a life sentence. here's abc's lindsey davis. >> reporter: the man accused of sexually abusing girls, one as young as 6 years old finally founds out his fate today. >> you do not deserve to walk outside of a prison ever again. >> reporter: crimes so traumatizing that when the former doctor for usa gymnastics was escorted out, the courtroom erupted in cheers. when you heard the judge announce 175 years, what was your reaction? >> i was so happy. because i know that he's never going to be going back out into the public and he's not going to be able to harm another girl again. >> reporter: 17-year-old stephanie robinson said she also suffered sexual abuse at the hands of nassar. >> learning how to deal with it and being able to talk about it. at first i was really afraid to speak about it or even let anyone know this happened to me and i was a victim of this. but now i know i'm a survivor. >> reporter: she testified last wednesday. her father by her side. >> i'm disgusted by your actions. may you never hurt or abuse another person again. >> reporter: stephanie was one of 156 women and girls who testified at nassar's sentencing hearing. >> you're pure evil. >> reporter: over the course of the last seven days. >> without my knowledge or consent, i had engaged in my first sexual experience by kindergarten. >> you hid for years behind olympic rings and a spartan head but there's nowhere left for you to hide, larry. >> i can't even put into words how much i [ bleep ] hate you. >> reporter: more than 150 women have accused nassar of sexual abuse. among them, some of the biggest names in usa gymnastics including gabby douglas and aly raisman. >> treatments with you were mandatory. lying on my stomach with you on my bed insisting that your inappropriate touch would help to heal my pain. >> some of the greatest athletes on earth and they're fearless and they deliver. one of the most important time of their lives and yet they're so vulnerable. >> reporter: many of these young women's testimony so heart breaking and difficult to hear, even nassar broke down as some of his victims spoke. >> wow. what have you done? >> she shook, took off his glazs and at times wiped away tears. today, it was nassar's turn to speak, making one last appeal for leniency. >> no words for this past several days. no words. they have had an emotional effect on myself and shaken me to my core. i also recognize that what i'm failing pales in comparison to the pain, trauma and emotional destruction that all of you are feeling. >> reporter: but the judge wasn't buying it. so highlight his insincerity, she read outloud, nassar ear earlier words in a letter to the court. in the letter, he claimed the victims were after media attention and money. >> hell hath no fury likeury lie woman scorned. the judge asked . >> reporter: the judge asked if he wanted to drit withdraw his guilty plea. but he wouldn't even say the word. >> do you want to take back your guilty plea? >> i said my plea. >> reporter: last november, nassar pleaded guilty to seven counts of first degree criminal sexual assault. his accusers say he would use his hand to penetrate them, claiming it was part of treatment. >> for all those involved for that insult, i'm horribly sorry. this was like a forest fire out of control. and i pray to the rosary every day for forgiveness. i want them to heal. >> reporter: the father of three was arrested in 2016 after this woman went public with what she said nassar did to her. >> this was just after my 15th birthday. i saw him for approximately a year and he abused me between 10 and 13 times during that time frame. he penetrated me vaginally and anally. >> reporter: she filed a complaint and told her story to "the indianapolis star." >> within hours, we had women calling the tip line. by the end of the day, we had 12 other survivors and it's grown from there. over 160 now. >> reporter: she was the last to testify today. >> you have fashioned for yourself a prison that is far, far worse than any i could ever put you in. and i pity you for that. >> reporter: but for many, nassar's sentencing is not the end. >> this is bigger than him. this is way bigger than him. this is about the institutions that protected him and to reiterate, all the statements that have been said before me, everyone in the world should be outraged right now. >> reporter: in claim that usa gymnastics and michigan state university turned a blind eye to nassar's abuse. >> who else at msu had received reports of larry's behavior and did not act? who else helped contribute to the greatest sexual assault scandal in history? >> reporter: three members of the usa gymnastics board have already resigned, including the chairman paul parilla. >> reporter: he had more than one accomplice. he was not only enabled by msu and usag, but they actually fed him in his crick tims. >> reporter: in recent days, team usa has pledged to protect athletes saying usa gymnastics will keep their words and experiences at the core of everything we do as with we remained focused on our highest priority -- the safety, health and well being of our athletes and creating a culture that empowers and supports them. and last week, the michigan state university president attended nassar's hearings to offer her support in person. >> i think there are steps being made towards accountability and other steps that will follow. >> reporter: but tonight, amidst fallout, simon submitted her letter of resignation. >> hearing what these young women had to say and the horrors of it over and over again, the president of michigan state could not survive that. and she should not have survived that. >> reporter: and both the ncaa and u.s. olympic committee have announced independent investigations to determine just who knew what and when. >> larry can be sentenced, but if these people are still allowed to be out in society and continue to do the same thing that they did to us, that neets going to fix anything. >> reporter: when we hear the back story and the horrors behind the scene in the shadows, you can't help but think that usa gymnastics put medals above these girls' lives. >> reporter: tonight, the so-called army of survivors is vowing to continue to fight for women everywhere. >> i'm excited to have a little girl one day hopefully and be able to raise her to know that she is powerful and she is strong and she does have a voice. because, you know, we have all been able to show our strength this week. >> reporter: for "nightline" i'm lindsey davis in lansing, michigan. >> our thanks to lindsey. and next, why these believers in a flat earth say the shape of our world is not settled science. crohn's disease. you're more than just a bathroom disease. you're a life of unpredictable symptoms. crohn's, you've tried to own us. but now it's our turn to take control with stelara® stelara® works differently for adults with moderately to severely active crohn's disease. studies showed relief and remission, with dosing every 8 weeks. stelara® may lower the ability of your immune system to fight infections and may increase your risk of infections and cancer. some serious infections require hospitalization. before treatment, get tested for tuberculosis. before or during treatment, always tell your doctor if you think you have an infection or have flu-like symptoms or sores, have had cancer, or develop any new skin growths, or if anyone in your house needs or recently had a vaccine. alert your doctor of new or worsening problems, including headaches, seizures, confusion, and vision problems. these may be signs of a rare, potentially fatal brain condition. some serious allergic reactions can occur. do not take stelara® if you are allergic to any of its ingredients. we're fed up with your unpredictability. remission can start with stelara®. talk to your doctor today. janssen wants to help you explore cost support options for stelara®. one laugh, and hello so i tried always discreet. i didn't think protection this thin could work. but the super absorbent core turns liquid to gel. snap! so it's out of sight... ...and out of mind. always discreet. for bladder leaks. if you could see your cough, you'd see all the sickness you're spreading. robitussin cf max. nothing lasts longer and treats more symptoms for your cough, cold and flu. 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but think about this. for the last 20, 25 generations, this is what we told people. >> reporter: unlike what we've been told in school, some flat earthers imagine the earth looks like a snow globe, round but not a sphere. the north pole is at the center of most flat earth maps with the ice of antarctica holding everything in. are you sure that is what the earth looks like? >> pretty sure. almost. the basic concept is sound. absolutely sound. and one thing again, we absolutely know for a fact this ain't it. >> reporter: those iconic blue marble images we see from space, they denounce them as fake. >> composite, animation, something that tells you this is not an actual photograph of the earth. >> reporter: so if you think you have questions, the flat earthers have many, many more. which is why i thought someone who has actually seen the earth from space might have some answers. >> 1 plus 1 i >> 2. >> jimmy: wh >> reporter: what color is the sky? >> blue. >> reporter: and the earth is? >> round. >> reporter: this professor spent more than 20 days in space and worked on the hubble telesco telescope. >> reporter: when you looked at the planet, what did it look like? >> it looks round, folks. it is round. my eyewitness account. and i looked at it as much as i could. it is round. >> we're in the final countdown. how you doing over there? >> reporter: he's played himself on "the big bang theory" but some flat earthers actually believe astronauts are just actors, part of a huge conspiracy going back to those very first steps on the moon. >> that's one small step for man, one giant leap for mankind. you don't believe they've gone to space? >> no. the rockets go up, sure. there's nobody in them. >> reporter: rob skiva is another up with of the celebrity contrarians in the flat earth movement. his popular youtube videos and podcasts take clues from the bible's book of genesis. >> reporter: there's no way you can get a spinning globe in the bible. i have become skeptically of everything. rightfully so. >> pretty much everything here is a conspiracy theorist. >> that's a common trait. but there's little bit conspiracy theorist in all of us. . >> reporter: it's why many of them do their own experiments. there's going to be some sciency people who say that is a real bogo experiment. >> they have. >> reporter: that's a little basic. >> i know. it's so simple it will go right over your head. >> reporter: the credo for many of these believers is check it out for yourself. >> go out and test. >> reporter: you just want them to ask the questions. >> why do you believe what you believe? and go from there? i could tell you something and you just look at me and say i'm crazy. >> reporter: a lot of people watching this will say that man is crazy. >> i'm sure they probably do. i would say well, they're crazy for not testing what they think they believe. >> reporter: but in a world of disagreements, large and small, for something as clear as this horizon, the interpretation could be infinite. for "nightline" i'm eva pilgrim in carey, north carolina. and next, leave on elton john. how the legendary rocker says he wants to be remembered after retirement. that cough doesn't sound so good. well i think you sound great. move over. easy booger man. take mucinex dm. it'll take care of your cough. fine! i'll text you in 4 hours when your cough returns. one pill lasts 12 hours, so... looks like i'm good all night. ah! david, please, listen. still not coughing. not fair you guys! waffles are my favorite! ah! why take 4-hour cough medicine? just one mucinex lasts 12 hours. start the relief. ditch the misery. let's end this. touch is how we communicate with those we love, but when your psoriasis is bad, does it ever get in the way? 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>> that i gaye people a hell of a lot of pleasure, that my songs will live on, that i will not be disappearing and i'll be making music. >> you can watch the full interview tomorrow on "good morning america." congrats to elton john, living his dream. it's unknown who said, quote, every morning you have two choices -- continue to sleep with your dreams or wake up and chase them. thank you for watching "nightline." as always we're online on our facebook page. thanks for the company, america. good night. sfx: tsfx: feet shufflingc life can change in an instant. be covered when it does... ...with a health plan through covered california. we offer free expert help choosing the best plan for you. and all of our plans include free preventive care. financial help is available, so check for yourself to see what savings you qualify for. open enrollment ends january 31st, so don't miss out. because you never know when life... ...will change. get covered today.