Aligning the broad bandwidth seed source for the 10PW Vulcan upg. Image by: STFC
Just how long, big, loud or bright something is, are just a few of the millions of things that science experiments around the world are measuring right now. Since science began, all its experiments look to measure a variable to test a hypothesis. As new discoveries are made new questions are asked and new, more precise and sensitive measurements are needed.
How we measure something (the equipment we use, the units of measurement, how long it will take to get them and how best to collect and process the data) very much depend on what the object is. For example, you wouldn’t go about measuring the length of a football field in the same way you would measure the volume of water in your fish tank. And the type of measurement may also be different.
The type of measurement that the experiment collects can also vary. There are two types of measurement: direct and indirect. Direct measurement refers to measuring exactly the thing that you want to measure. Indirect measurement refers to when you measure what you want by measuring something else. For example, you can directly measure how long a piece of string is by using a ruler. But measuring something like the wind’s speed is more difficult as it’s tricky to measure the actual speed of the wind. But by measuring how much power a windmill makes, it is possible to work backwards and calculate from this how fast the wind must be. This would be an indirect measurement.
Collecting these measurements is essential but it’s not always easy. Engineers have the exciting, challenging and very rewarding job of designing the sensitive detectors, actually making the equipment, testing that it can withstand the sometimes demanding experimental environments and then ensuring that they run well for the duration of the study. This process takes a whole team of engineers to complete. It could take no time at all, or it could take several years to get from the design phase to running it.