Oh yeah, your lecturer must have visited one of the countries in the arctic circle. Some of them experience 24 hours of sunlight for about six month.
Countries like Sweden, Denmark, Finland, Norway, Canada, Alaska etc. experience the midnight sun as it is called for varying lengths of time. Only the part of the countries that crosses the Arctic circle experiences it though.
Alaska is a state in the US, not a country, sorry about that.
Thanks for reading through!