Astronomy

The Fading Stars: Exploring Global Light Pollution

Astronomy, Physics, Science / By

A pollution that you can expect no one to talk about, is Light Pollution. Harmless at a glance, but poses an underlying depth of detriments. 

According to the Oxford Dictionary, Light Pollution is the existence of too much artificial light in the environment, for example from street lights, which makes it difficult to see the stars. But do the effects stop here? Most certainly not.

Disrupting the natural patterns of wildlife, an increase in the release of carbon dioxide into the atmosphere, and complicated health problems are just fractions of the effects that the majority of the populace in urban areas are turning a blind eye to. So much coming from a small bulb hanging in your room huh? But why is the light radiation coming out of a simple light bulb posing such a threat you may ask?

Well, as the Nepali saying goes “Too much sugar is bitter”, and so is the case with bulbs. Few of them pose almost zero to negligible effect but in the context of urban areas housing 4.4 billion inhabitants, things get complicated.

Diving into the sole causes responsible for light pollution, the ones making the headlines are the residential lights and the dense populace.

This image helps us depict how light radiation in different areas across the United States varied over the past few decades. A general trend we can notice is that, as the population increased the brighter the night was.

When a lot of sources of light emitting devices are concentrated in a small area, light emitted from say a bulb usually directed towards the ground covers a broad surface area while also increasing the space of the glare region. And like all mediums, the ground also acts as a medium for reflection, and the waves of light travel onto the sky only to be deflected by the heavy clouds. This causes for the light particles to be trapped and its appearance is that of a haze during night time.

The image by Anezka Gocova, in “The Night Issue”, Alternatives Journal 39:5 helps for better visualisation.

To bring forth the gravity of this situation, a prime example would be the L. A power outage, caused by an earthquake in 1994. Panicking residents rushed to inform authorities through 911 to complain about the Milky Way Cluster they were seeing. (similar to the image below taken by Forest Wander)

Mind you, this astounding night view was something all humans around the world could see at night back when proper lighting hadn’t been invented.

Scientists fear that with time, even the brightest stars would stop shining if the light pollution isn’t controlled and that children in the coming generations won’t aspire to study astronomy as there would be nothing to see in the night sky.

Relating to the Nepali saying again, It’s the collective effort that counts. Some little countermeasures that one can take to reduce the drastic effects of light pollution are:

  • Use motion-sensor lights.
  • Direct outdoor lights downward.
  • Replace bulbs with energy-efficient LEDs.
  • Dim or lower-intensity outdoor lights.
  • Install lighting only where needed.
  • Use window coverings to block light.
  • Don’t leave decorative lights on all night.

Could the universe be twice as old?

Astronomy, Physics, Science / By

The James Webb Telescope has been providing us with crucial information regarding our solar system, other galaxies and our universe. Not long ago, the telescope found six galaxies that could possibly be older than the universe, that is, older than the big bang, which is when scientists believe our galactic story began. 

These “universe breakers,” have already left astronomers and scientists puzzled – and therefore many of them have started to question if the universe is as old as we deem it to be. An article published by the Monthly Notices of the Royal Astronomical Society, claims that the universe might be almost double its current estimated age – 26.7 billion years old. What proof do they have to claim this?

Measuring the age of the universe?

The redshift phenomena – put in simple words, the rate of expansion of the universe, is what scientists and astronomers use to understand and estimate the age of the universe. 

When red light travels, its wavelengths are much longer than violet/blue light waves. Longer wavelengths indicate that light is reaching us from a place in space that is almost impossible to reach, it’s very far away. This is how scientists measure how far away things are in this cosmos. It is also how the James Webb Telescope (JWT) was able to identify those six galaxies.

CC: James Webb telescope detects evidence of ancient ‘universe breaker’ galaxies

The Proof:

The galaxies founded by JWT were almost 13.5 billion years old – when the universe was just a baby. The likelihood of celestial objects to exist when the universe was in its earliest stages is almost impossible. 

Not to mention, these galaxies seem to be far too advanced to have existed in the universes’ early stages.

Other than these galaxies, there is Methuselah. This star appears to either be older than the universe itself, or has existed since the early stages of the universe. 

Though the findings of the universe being almost 27 billion years old seem convincing, only few research papers and genuine proofs have been submitted by university scientists and space research organisations. 

Quasars Show that Time was Slower in the Early Days of the Universe

Astronomy, Must Read, Physics, Science / By
Artist’s rendering of the accretion disc in ULAS J1120+0641, a very distant quasar powered by a supermassive black hole with a mass two billion times that of the Sun. Image: https://en.wikipedia.org/wiki/Quasar

(Astronomy) A team of astronomers led by Geraint Lewis, the astrophysics professor at the University of Sydney’s School of Physics, have recently proven that time in the early days of the universe, roughly 1 billion years ago, was significantly slower than time at the present day. By looking at quasars, incredibly active supermassive black holes, the team was able to determine how much the present universe has sped up compared to the distant past. This claim also buttresses Albert Einstein’s General Theory of relativity, which states that the passage of time was slower for the distant universe in the past.

Five times slower. That’s how slow Professor Lewis’ team found time to be in the universe’s earliest stage. To quote Professor Lewis: “If you were there, in this infant universe, one second would seem like one second — but from our position, more than 12 billion years into the future, that early time appears to drag.”

This discovery will have a massive impact on other astronomers. Understanding the passage of time in the beginning of the universe can help them not only figure out the endgame of the universe, but also such questions as How was the universe formed? and Are there other universes besides ours?