Alan Willison, of Hertford Astronomy Group, continues his guide to astronomy, this time looking at using light to decode the universe's origins.

Welwyn Hatfield Times: Alan WillisonAlan Willison (Image: Alan Willison)

The universe has always fascinated humanity, with its vastness and countless mysteries waiting to be unravelled. Last month we looked at how looking into space was like looking at a time machine.

The distance of objects in space could be measured in the amount of time it takes for their light to reach us. One of the key tools in the quest to understand the origins of the universe is the analysis of that light.

By studying cosmic illumination, scientists are able to delve deeper into the formation of our universe and unlock its secrets.

Light analysis allows us to peer into the depths of space and observe celestial bodies that are billions of light years away. Through this scientific exploration, we can gather crucial data about distant galaxies, stars, and even remnants from the early days of our universe.

By decoding the messages carried by light, scientists can uncover vital clues about how our universe came into existence. This fascinating field not only helps us understand our place in the cosmos but also sheds light on fundamental questions about life itself.




As we continue to push boundaries in scientific research, it is through light analysis that we can make significant breakthroughs in unravelling these mysteries. The use of advanced technology and innovative techniques enables us to capture and interpret cosmic illumination like never before.

The study of light has always been a guiding force in human progress, from ancient civilizations using sunlight for navigation to modern-day telescopes capturing breathtaking images from distant corners of space.

It is through this age-old fascination with light that we continue to expand our understanding of the universe's origins.

Spectral analysis is a powerful tool that allows scientists to unravel the mysteries of the universe by examining the colours of light emitted by celestial objects. By studying these cosmic spectra, researchers can gain valuable insights into the different phases of the universe's evolution.

One key phenomenon that spectral analysis helps us understand is redshift and blueshift. When an object in space is moving away from us, its light appears shifted towards longer wavelengths, resulting in a redshift.

Conversely, if an object is moving towards us, its light appears shifted towards shorter wavelengths, creating a blueshift. By analysing these shifts in the spectrum of light emitted by distant galaxies and stars, scientists can determine their velocity and distance from Earth.

Can this be done at home? Well, Jack Martin does this with some very impressive (expensive) kit. Jack Martin runs the Huggins Spectroscopic Observatory UK.

Another crucial aspect of spectral analysis is its role in studying the cosmic microwave background radiation (CMB). This faint glow permeating throughout space is considered to be one of the most significant pieces of evidence supporting the Big Bang theory.

By analysing its spectrum, scientists have been able to gain insights into the early stages of our universe's evolution and understand how it has expanded over time.




Galaxy surveys and redshift surveys have played a significant role in this pursuit. By meticulously observing the distribution of galaxies and measuring their redshift, scientists can unravel the intricate web that connects these celestial bodies. These surveys provide invaluable data points that help us understand how galaxies are distributed across space.

Another fascinating technique used in mapping large-scale structures is gravitational lensing. This phenomenon occurs when light from distant objects is bent by massive objects along its path.

By studying this bending effect, scientists can infer the presence and distribution of matter in the universe, including filamentary structures that form the cosmic web.

The cosmic web itself is a breathtaking sight to behold. It consists of vast networks of interconnected filaments stretching across unimaginable distances, binding galaxies together like an intricate tapestry.

Mapping these filaments provides crucial insights into how matter is distributed on a grand scale and offers clues about the formation and evolution of our universe.

Welwyn Hatfield Times:

The study of the birth of stars and galaxies is an awe-inspiring field that relies heavily on the use of advanced tools and technologies. Among these tools, telescopes play a crucial role in enabling astronomers to unravel the mysteries of our universe.

Through the power of light-based observations, astronomers are able to delve into the depths of space and witness celestial phenomena that occurred billions of years ago.

One key aspect of studying the birth of stars and galaxies lies in spectroscopy, a technique that allows scientists to analyse the light emitted or absorbed by celestial objects.

By breaking down this light into its constituent wavelengths, astronomers can gain valuable insights into the composition, temperature, and motion of stars and galaxies.

Photon detection is another essential tool in this field. Highly sensitive detectors enable astronomers to capture even the faintest traces of light from distant cosmic sources.

This enables them to gather data that can shed light on the formation processes occurring within these celestial bodies.

Furthermore, celestial photography has revolutionised our understanding of star and galaxy formation. By capturing stunning images through telescopes equipped with advanced cameras, scientists are able to document these cosmic events with unprecedented detail and clarity.

The study of the early universe and cosmic inflation has always fascinated scientists, as it holds the key to understanding the origins of our universe. One of the most remarkable tools in this quest is the cosmic microwave background (CMB), a faint glow left over from the Big Bang.

However, researchers are now exploring an even more intriguing avenue - capturing ancient light echoes to delve deeper into this cosmic history.

The concept of primordial light echoes is based on the inflationary theory, which suggests that our universe underwent a rapid expansion in its infancy. This expansion would have caused ripples or fluctuations in space-time, leaving imprints on the CMB radiation.

By studying these echoes, scientists hope to uncover valuable insights about the early stages of our universe and confirm or refine our understanding of cosmic inflation.


Photo of the Month 

Welwyn Hatfield Times: The Horsehead Nebula B33 and Flame Nebula NGC 2024The Horsehead Nebula B33 and Flame Nebula NGC 2024 (Image: Kevan Noble)

The Horsehead is a dark nebula made of opaque obscuring dust which blocks the light from the nebulae and stars behind it. It is located about 1,500 light years away.

The Flame Nebula (the yellow flare on the left of the image), approximately 1,000 light years away, glows because nearby stars are releasing ultraviolet light that causes hydrogen in the nebula gas cloud to lose an electron.

When this electron recombines with the hydrogen, it releases the light we see.

Taken by Kevan Noble from his back garden, comprising five hours of exposure.


For more on Hertford Astronomy Group, visit