I have data of an orbital parameter of a satellite for 456 days. I am treating this data as univariate time series data and wish to use time series models to forecast future values. However, this data seems quite complex. This data appears as sinusoidal oscillating within a sinusoidal function.
I tried using 2nd order differential to make the series weak stationary but still my ACF and PACF plots give a lot of values that exceed the confidence interval. Using all those values would give a very poor model. I wish to ask that whether my data can be treated as time series data and whether classical algorithms such as ARIMA etc can be used for forecasting.
I have uploaded the plot of original data, its 2nd differential and PACF of 2nd differential: