like this?

\documentclass[12pt]{article}
\usepackage[showframe]{geometry}
\usepackage{booktabs}
\begin{document}
\begin{center}
\begin{tabular}{c}
\midrule
DS: Probability \& Geometry \\
Location: Somewhere over the rainbow \\
\midrule
\end{tabular}
\end{center}
Bla, bla, bla, bla, bla, bla, ...
\end{document}
edit:
if you like to change midrule thickness, you can add option with thickness as for example \midrule[3pt]. also for top rule you can use \toprule or \toprule[2pt]. for more details see documentation of package booktabs.
rules are longer than text for \tabcolsep on each side of table cell. its default size is 6pt, but you can change size with \setlength\tabcolsep{<desired length>}. An example considering this is:
\documentclass[12pt]{article}
\usepackage[showframe]{geometry}
\usepackage{booktabs}
\begin{document}
\begin{center}
\setlength\tabcolsep{12pt}
\begin{tabular}{c}
\toprule[2pt]
DS: Probability \& Geometry \\
Location: Somewhere over the rainbow \\
\midrule[3pt]
\end{tabular}
\end{center}
Bla, bla, bla, bla, bla, bla, ...
\end{document}

If you want to set a factor, say 20%, of overshoot,
\documentclass[12pt]{article}
\usepackage[showframe]{geometry}
\usepackage{booktabs}
\begin{document}
\begin{center}
\begin{tabular}{c}
\toprule[2pt]
\makebox[1.20\width]{% 20% longer rules
\begin{tabular}{@{}c@{}}
DS: Probability \& Geometry \\
Location: Somewhere over the rainbow
\end{tabular}%
}\\
\midrule[3pt]
\end{tabular}
\end{center}
Bla, bla, bla, bla, bla, bla, ...
\end{document}

\setbox0\hbox{Location: Somewhere over the rainbow}the width is then\wd0. Note that this is not expandable and you should evaluate\wd0close to the\setboxbecause it will be invalid if something else uses that box. – Skillmon Nov 21 '17 at 19:19