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\rhead{ \footnotesize {YOUR NAME \\ Lecture Notes for ESA666 : Insert Date Here}}

\begin{document}

\begin{center}
\noindent {\bf{\textsf{The Milky Way Galaxy}}}
\end{center}

\begin{itemize}

\item The text below is only an example. You can draft the notes in any way you want. A convenient approach is to list the salient points in bullets. Put all the necessary equations in. If you can find online a figure corresponding to the figure shown in class, include that as well. 

\item Cosmology is the scientific study of the large scale properties of the universe as a whole. Like any field of science, cosmology involves the formation of theories or hypotheses about the universe which make specific predictions for phenomena that can be tested with observations. Depending on the outcome of the observations, the theories will need to be abandoned, revised or extended to accommodate the data. The prevailing theory about the origin and evolution of our Universe is the so-called Big Bang theory.

\item The term redshift is defined as a dimensionless number $z$, where 

\begin{equation}
\large{z = \frac{\lambda_{obs} - \lambda_{rest}}{\lambda_{rest}}}
\end{equation}

\item Historically, the measurement of H$_0$ has fluctuated a great deal. 

\begin{enumerate}

\item 1940 - 1960s (Baade \& Sandage) : 50 - 150 {\kms}~Mpc$^{-1}$

\item Hubble Key Project (2001) : $72~{\pm}~8$~{\kms}~Mpc$^{-1}$

\item WMAP (2003, 1 year data) : $72~{\pm}~5$~{\kms}~Mpc$^{-1}$

\item WMAP (2011, 7 year data) : $70.2~{\pm}~1.4$~{\kms}~Mpc$^{-1}$

\item Planck (2013) : $67.3~{\pm}~1.2$~{\kms}~Mpc$^{-1}$

\end{enumerate}

\item The following figure explains the trend in the expansion of the universe

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\end{itemize}

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