# Science

The Science Team is investigating what we can actually observe with XRT-Station. We are currently focusing on the 21 cm hydrogen line. By observing this radiation we can probe the structure and motion of the Milky Way, and eventually estimate the mass of the galaxy! This involves a detailed understanding of both the science behind the observations and the technical aspects of measuring this radiation.

## Amplifiers: Temperamental, but Necessary

### 16 February 2015

XRT-C members were given a demonstration of a working radio telescope at the University of Exeter by lecturer and veteran radio astronomer, Dr. Chris Brunt. Throughout the demonstration, Chris stressed the importance of high quality electronics and a low noise environment for your telescope. Satisfying these two factors can make your observing time much easier….READ MORE

### 24 January 2015

The XRT-C procurement team have successfully ordered the the Spectracyber 1420 MHz Hydrogen Line Spectrometer/Continuum receiver from Radio Astronomy Supplies. This state of the art receiver observes 1420±2 MHz with a band width of 10KHz which is ideal for observing Neutral Hydrogen and the 21cm emission line. In addition the component comes with a purpose…READ MORE

## XRT-C Frequently Asked Questions #1

### 14 January 2015

Last year was a great year for the XRT-C project. We finally found a home for our telescope, secured enough funding to keep the project running and got some of the components bought and ordered in preparation for construction later this year. While attending outreach events, there’s been nothing we enjoy more than interacting with…READ MORE

## UKSEDS Astronomy Workshop 2015

### 14 November 2014

UKSEDS have announced an astronomy workshop, to be held Jan 24th at the University of Oxford. XRT-C will be looking to send a large delegation to learn about the science of observations and possibly present about radio observations.

## Goonhilly meeting

### 04 July 2014

XRT-C team leaders meet with the new heads of Goonhilly Earth Station today. Goonhilly Earth Station is a large, professional observatory based in deepest, darkest (ideal for observations) Cornwall. They’ve recently gone through a bit of an overhaul in ownership but their new owners are keen to expand and encourage student involvement in the site….READ MORE

## Important – Project schedule update

### 29 April 2014

The XRT-Station project has taken some important steps forward over the last few weeks. The Team leadership have been taking this recent progress as a chance step back and review the progress of the project. Back in November last year we composed a plan for the project. By May we were hoping to have secured…READ MORE

## The Radiometer Equation: Part II

### 24 March 2014

The system temperature Following on from The Radiometer Equation: Part I. The system temperature comprises of the noise generated by things above the antenna that you don’t want to be detected and the thermal noise of the electrical components (e.g. the mixer or amplifier). The noise generated by external sources can be reduced by ensuring…READ MORE

## The Radiometer Equation: Part I

### 22 March 2014

The radiometer equation is one of the fundamental equations of radio astronomy. It defines the ratio of signal to noise. It will determine whether you can see a source given your telescope set-up and external conditions. It is given by, $$\frac{\mbox{Signal}}{\mbox{Noise}} = \frac{\mbox{Source Temperature}}{\mbox{System Temperature}} \sqrt{\mbox{Bandwidth} \times \mbox{Integreation Time}}$$ This post will look at…READ MORE

## Our View to the Centre of the Galaxy

### 14 March 2014

Black holes are notoriously difficult to observe, so most of the evidence for a black hole is based on its influence on the surrounding area; rather than direct observations of the black holes themselves. Astronomers can study how objects around the black hole, such as gas clouds and stars, are affected by its strong gravity…READ MORE

## The Hydrogen Line V: Dark Matter

### 10 March 2014

In the last post we talked about using Newtons theory of gravity to calculate the mass of the Milky Way using the velocity of hydrogen clouds which we can measure with XRT-S. An example of this data from another similar project is shown below. This is called a rotation curve and plots the measured orbital…READ MORE

## The Hydrogen Line IV: Newton’s Gravity

### 01 March 2014

In the last post we focused on measuring the Doppler shift of radiation emitted from clouds of hydrogen in the Milky Way and how this can tell us about the velocity, or motion, of the gas clouds. Building up a map of velocities of many different gas clouds throughout the Milky Way enables us to…READ MORE

## The Hydrogen Line Part III: Galactic Motion

### 19 February 2014

In previous posts we have explained how radiation is emitted by hydrogen atoms in space to form the hydrogen 21-cm line radiation. We have also introduced Doppler shift which alter the wavelength of this radiation. In this post we will talk about how we can use these two processes to learn about the structure of…READ MORE