These may be the darkest points in outer space

The question of darkness has long fascinated humanity, and with the advancement of space exploration, it is only natural to wonder whether outer space might contain a uniquely dark point against which everything else appears bright or illuminated.

For most people, space is imagined as a fundamentally dark, desolate, incomprehensible void, about which our knowledge remains sadly limited — far more questions exist than available answers.

It is therefore reasonable to ask whether space truly is as dark as it seems at first glance, and whether there is a single point darker than all others. According to space researchers, answering this is complicated by the fact that what we consider “darkness” depends on an enormous number of factors, LiveScience reports.

Total darkness is rarer than you might think

Although the space between stars appears pitch-black at first sight, vast amounts of dust are present throughout the cosmos, scattering and transmitting light. This means the night sky appears far brighter than it would if its illumination depended solely on starlight.

Because this creates the effect of a kind of background lighting filling much of the universe, true absence of light is extremely rare. Moreover, the basic colour of space is not black at all, but a slight beige tone — often referred to in scientific circles as “cosmic latte”.

According to Andreas Burkert, an astrophysicist at the University of Munich, precisely defining the concept of darkness may be the key. Visible light is not the only wavelength in the electromagnetic spectrum — gamma rays and UV radiation also reach distant parts of the universe, meaning there may be light present even where our eyes perceive only darkness.

Can darkness be measured?

If we consider only visible light, we can indeed identify distinctly dark places in outer space, and their measurement can be aided by the concept of albedo.

This term refers to the proportion of incoming light that a surface reflects. A perfectly functioning mirror, for example, has an albedo of 1, since it reflects 100% of the light that hits it.

By contrast, the darkest known point in the Solar System — the 8-kilometre-long nucleus of Comet Borrelly, composed of ice and dust — reflects only 3% of the Sun’s light.

Black holes also form a special category: although their name suggests that darkness reigns within them, this is far from the case. Burkert points out that intense light becomes trapped in these structures, and it is simply for this reason that they appear dark.

There are several reasons something might be dark in outer space

Darkness may arise when a surface never receives light at all — such as the permanently shadowed craters on the Moon or Pluto. In other cases, dense dust clouds such as Bok globules completely absorb the visible light of nearby stars, making them appear as dark patches in the sky. However, in the infrared spectrum they become far easier to penetrate.

The regions located at the edges of galaxies, far from any light sources, are also extremely dark: according to measurements from New Horizons, the sky there is on average ten times darker than it is near Earth, though cosmic background light still illuminates them to some extent.

In addition to all this, Earth itself lies within a dark, bubble-like void in the Milky Way, which allows us to observe distant stars with minimal interference — and if this were not the case, Burkert argues, our understanding of the universe would likely be far more limited than it is today.

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