Our Galaxy Could Be Evaporating As Dead Stars Flee The Milky Way

A recent study in the Monthly Notices of the Royal Astronomical Society has come up with a model that could locate stellar relics like stellar black holes even though we haven’t detected enough of them to produce an observed map of their general location. They also said that our Galaxy could be evaporating as they try to flee the Milky Way.

Even the most dazzling stars eventually pass away. In actuality, the stars with the brightest light also have the shortest lifespans.

Within a few million years, they exhaust all of their hydrogen, which causes them to erupt as bright supernovae. Their remaining cores disintegrate into neutron stars or black holes. Like a cosmic cemetery, these little, black particles are strewn around our galaxy.

It is challenging to find stellar black holes and neutron stars. Since neutron stars are just fifteen kilometres across, they are often missed unless their magnetic poles are aligned to allow us to observe them as pulsars.

Stellar Black holes are even smaller and emit no light of their own. Most would only be visible when they pass between us and a more distant star, so they may be found by microlensing. Some appear as microquasars when they consume the mass of a companion star.

However, a recent study in the Monthly Notices of the Royal Astronomical Society has modelled where we could locate these stellar relics even though we haven’t detected enough of them to produce an observed map of their general location.

They studied the star distribution in our galaxy and ran simulations to see how stellar interactions might pull and deflect the stellar remnants. These “graveyard stars” are usually older than the stars in the current galaxy because they have had more time to move to new orbital paths.

As one may anticipate, the positions of the stellar remnants statistically exhibit some degree of blurring. These stars are distributed in a plane that is three times thicker than the visible Milky Way. But the group discovered a feature of their distribution that was extremely unexpected.

This galaxy is ejecting about one-third of these ancient, dead stars. According to their hypothesis, a third of stars have had close stellar encounters that have given them a speed boost that will eventually allow them to escape the Milky Way’s gravitational pull.

In other words, the ghosts are escaping the cemetery.

This indicates that, unexpectedly, the Milky Way is “evaporating,” or losing mass, over time. Since the Milky Way is significantly more massive than small star groups like globular clusters, one would assume that long-term evaporation would be low.

Another part of the model that surprised people is how equally scattered these star remnants are over the Milky Way. Most stars should be within 100 light years of a stellar remnant.

The closest star remnant to the Sun is most likely located approximately 65 light years away. So we could have a celestial ghost in our backyard and not even know it.

As we previously reported, the other planets may eventually collide with one another or be ejected out of the solar system if a star passing through our solar system changes Neptune’s orbit by just 0.1 percent, which can result in the Earth and the entire solar system collapsing.

We’re increasingly likely to see microlensing occurrences when more sky survey observatories, like Rubin Observatory, go online and start collecting data. The galactic underworld will then finally become visible to us.