The Institute of Astronomy (IoA) came into being in 1972 by the amalgamation of three institutions which had developed on the site. These were the Cambridge University Observatory which was established in 1823, the Solar Physics Observatory (1912) and the Institute of Theoretical Astronomy (1967).

The IoA is a department of the University of Cambridge and is engaged in teaching and research in the fields of theoretical and observational Astronomy. A wide class of theoretical problems are studied, ranging from models of quasars and of the evolution of the universe, through theories of the formation and evolution of galaxies and stars, X-ray sources and black holes.

Much observational work centres around the use by staff of large telescopes abroad and in space to study quasars, galaxies and the chemical constitution of stars. A programme on the velocities of stars is conducted using the 36-inch telescope in Cambridge. Instrumentation development is also an important area of activity, involving charge coupled devices and detector arrays for rapid recording of very faint light and the design and construction of novel spectrographs.

### Recent Submissions

• #### GRS 1739-278 OBSERVED AT VERY LOW LUMINOSITY WITH $\small \textit{XMM-NEWTON}$ AND $\small \textit{NuSTAR}$ ﻿

(IOP Publishing, 2016-12-01)
We present a detailed spectral analysis of $\small \textit{XMM-Newton}$ and $\small \textit{NuSTAR}$ observations of the accreting transient black hole GRS 1739−278 during a very faint low hard state at ~0.02% of the ...
• #### The mass distribution of the unusual merging cluster Abell 2146 from strong lensing ﻿

(Oxford University Press, 2017-01-11)
Abell 2146 consists of two galaxy clusters that have recently collided close to the plane of the sky, and it is unique in showing two large shocks on $\textit{Chandra X-ray Observatory}$ images. With an early stage merger, ...
• #### Do sound waves transport the AGN energy in the Perseus cluster? ﻿

(Oxford University Press, 2017-01-01)
The level of random motions in the intracluster gas lying between 20 and 60 kpc radius in the core of the Perseus cluster has been measured by the Hitomi Soft X-ray Spectrometer (SXS) at 164 ± 10 km s$^{−1}$ . The maximum ...
• #### A 78 Day X-Ray Period Detected from NGC 5907 ULX1 by $\textit{Swift}$ ﻿

(IOP Publishing, 2016-08-10)
We report the detection of a 78.1 ± 0.5 day period in the X-ray light curve of the extreme ultraluminous X-ray source NGC 5907 ULX1 (L$_\text{X,peak}$ ~ 5 × 10$^{40}$ erg s$^{-1}$), discovered during an extensive monitoring ...