What will the Milky Way look like in 4.5 billion years?
Within 4,500 million years, many things will have changed in the universe that surrounds us;
by that time, the sun will already be in its last stage of life, with only a few million
years remaining before it becomes a red giant and, in turn, the Milky Way and Andromeda galaxy will
have started to merge to form a single galaxy. But... What will happen when both galaxies
merge? Will it be the end of the Milky Way as we know it? Will the solar system survive
this galaxy merger? Join us to find out!
Throughout history, humanity has been fascinated by space and has explored the
wonders of the universe through technology and science, which allow us to know what
some objects were like in the past and what they will look like in the future.
This time we have to talk about our galaxy, the Milky Way. Would you like to know what
changes it will undergo in the next 4.5 billion years when it merges with the Andromeda Galaxy?
Andromeda galaxy The Andromeda Galaxy, the closest
neighboring galaxy to the Milky Way, this galaxy has been studied and observed since ancient times.
In his writings in the 10th century, the Persian astronomer Al- Sufi described it as a nebula and
not a galaxy. In the 18th century, Charles Messier included it in his catalog of celestial objects.
The discovery that the Andromeda Galaxy is a galaxy and not a nebula was a breakthrough in
understanding the universe and changed our worldview. This discovery was made by the
American astronomer Edwin Hubble in 1923, and it was a turning point in the history of astronomy.
Before Hubble, it was believed that the Milky Way was the only galaxy in the universe and
that all nebulae were part of it. However, Hubble was able to show that the Andromeda
Nebula was a separate galaxy and that there were many other galaxies in the universe.
Hubble reached this conclusion through his work at the Mount Wilson Observatory in California,
where he used a 100-inch telescope to observe the Andromeda Nebula. By studying the light
from stars in the galaxy, Hubble realized that they differed from stars in our galaxy.
He discovered that these stars were brighter and more prominent than the
stars in the Milky Way and that the nebulae surrounding the galaxy were star clusters.
From these findings, Hubble determined that the Andromeda Nebula was a separate galaxy
similar to ours. Furthermore, he realized that there were many other galaxies in the universe
and that these galaxies were much larger and more complex than previously thought.
This discovery significantly changed our understanding of the universe,
ushering in a new era of research and discovery in astronomy. It allowed us to realize that the
Milky Way was only a tiny part of a much larger and more complex universe and that there was much
more to explore and discover. An imminent collision
During his research on the Andromeda Galaxy in the 1920s, Hubble discovered that the Andromeda
Galaxy was moving toward the Milky Way at a speed of about 300 kilometers per second.
This discovery caught the attention of astronomers since it meant that at that speed, both galaxies
would end up colliding in the future. However, it was not known precisely how long it would
take since we did not have an exact measurement of the distances that separated both galaxies.
In his work, Hubble used a technique called "Cepheid law," which allowed him
to measure the distance to the galaxy with a precision never seen before.
The Cepheid law is based on the fact that certain stars, called Cepheids,
have a period of brightness that correlates with their intrinsic luminosity. By measuring
the brightness period of a Cepheid, its luminosity can be estimated, and from there, its distance can
be calculated using the inverse square law. Hubble used this technique to measure the
distance between the Milky Way and the Andromeda Galaxy and found it was
approximately 900,000 light years from Earth. This distance placed Andromeda far beyond
any calculated object, even beyond the edge of the Milky Way. For this reason,
is considered an achievement in astronomy. However, this figure pales compared to the real
distance between the two galaxies, which today is known to be more than 2.5 million light years.
Until recently, it was not known precisely how many years the two galaxies would collide,
but that changed in 2012 when a team of astronomers led by N. Wyn Evans and Vasily
Belokurov of the University of Cambridge used the Hubble Space Telescope to calculate the
time remaining for the two galaxies to merge. With the help of the mighty space telescope,
the team discovered a new class of variable stars in the Andromeda Galaxy. These variable stars,
known as RR Lyrae stars, are used as indicators of distance and age in the universe. By studying
the number of RR Lyrae stars in the Andromeda Galaxy, Evans and Belokurov 's team could estimate
the galaxy's age and, thus, the amount of time until the Milky Way and Andromeda Galaxy merge.
The team found that the Andromeda Galaxy is about the same age as the Milky Way and that the two
galaxies will merge in the distant future in about 4.5 billion years. As the two galaxies get closer,
they will interact gravitationally, eventually merging into a single galaxy.
Since then, other studies have confirmed and refined these time estimates using various
astronomical techniques, including measuring the speed and position of stars in both galaxies.
In general, the calculations suggest that the merger between the Milky Way
and the Andromeda Galaxy is inevitable and will happen in the distant future.
Milkdromeda Galaxy In about 4.5 billion years,
the Andromeda Galaxy and Milky Way will begin to merge. This process will take a few billion
years to complete. During this time, the two galaxies will move through space, gravitationally
interacting with each other and producing a wave-like effect in the arms of each galaxy.
The merger process will begin with a collision between the clouds of gas and dust at the edges
of the galaxies, which will cause the formation of new stars. These stars will start forming clusters
and moving towards the galaxies' center. As the galaxies get closer to each other, the stars will
begin to orbit around the combined centers of masses of the two galaxies. Gas and dust will
compress and heat up in the centers of galaxies, causing an increase in the star formation rate.
Once the galaxies merge, a new galaxy will be formed that will result from combining
both galaxies. The resulting galaxy will have a more significant number of stars
and an oval shape. The Milky Way and the Andromeda Galaxy are similar in size,
and once they merge, the resulting new galaxy will be much larger than the original galaxies.
The galaxy resulting from the merger between the Milky Way and the Andromeda Galaxy may
receive a new name. The merger of both galaxies is known as the " Milkdromeda Galaxy, " but this
name is provisional and may change once the merger occurs. In any case, the scientific community will
likely discuss and agree on a name that adequately reflects the new galactic structure resulting from
the merger of these two large galaxies. What will this new galaxy look like?
The Milky Way will look very different as the merger with the Andromeda Galaxy approaches.
Currently, the Milky Way has a spiral shape with four primary arms. However,
as it merges with the Andromeda Galaxy, the resulting new galaxy will have an oval shape
with many stars orbiting the galaxy's center. The spiral arms of the Milky Way will deform
and mix with the spiral arms of the Andromeda Galaxy, giving rise to a new galactic structure.
The merger process will also cause an increase in the number of stars visible in the night sky.
Currently, the Milky Way contains about 100 billion stars, but once it merges with the
Andromeda Galaxy, the resulting new galaxy will contain about a trillion stars. This
increased number of stars will make the galaxy much brighter in the night sky,
and details of galactic structure may even be visible to the naked eye during the day.
Supermassive black hole The merger of the two galaxies, the Milky
Way and the Andromeda Galaxy, will significantly impact their central supermassive black holes.
These black holes are expected to merge to form an even larger and more massive black hole.
Both galaxies have a supermassive black hole at their center; the supermassive
black hole at the center of the Milky Way is called Sagittarius A*, while the one in the
Andromeda Galaxy is called Messier 31, or M31 for short. Both black holes are enormous, with
a mass several million times the mass of the Sun. When the two galaxies merge, their supermassive
black holes will gravitationally attract each other and eventually
merge into a single, even larger black hole. This black hole merger is an exciting event
that emits gravitational waves, meaning that a disturbance occurs in the fabric of space-time.
In 2015, the scientific collaboration LIGO (Laser Interferometer Gravitational-Wave
Observatory) detected gravitational waves generated by merging two black
holes more than a billion light-years away. This demonstrated that detecting gravitational waves
is a valuable tool for studying and understanding the evolution of black holes and galaxy mergers.
The merger of the supermassive black hole into the resulting new galaxy may
also significantly impact the distribution of stars and matter in the galaxy and the
formation of new stars and planets in the future. These changes in the structure and composition of
the galaxy could have important implications for life and future evolution in the solar system and
the new galaxy resulting from the merger. What will happen to the solar system?
The merger of the Milky Way and the Andromeda Galaxy will affect the solar system,
moving through the resulting new galaxy and eventually settling into a new orbit around
the galaxy's center. What will happen to the planets and life on Earth? We will see later.
The merging of galaxies, however, will bring new stellar neighbors to our galactic
neighborhood. The stellar systems in the transition zone between both galaxies will
have a higher probability of gravitationally interacting with the stars of the solar system.
In addition, merging galaxies can also increase the rate of supernova formation,
which could impact the amount of cosmic radiation reaching Earth.
The merger of the Milky Way and the Andromeda Galaxy will significantly impact the solar system.
However, it is essential to note that this event will not occur for about 4.5 billion years, so
rest assured, there is nothing to worry about now. The merger of the two galaxies will influence the
distribution of stars and matter in the resulting galaxy, which may affect the formation of new
stars and planets. The solar system could be in a new region of the galaxy with different
environmental conditions, such as higher cosmic radiation or a higher density of nearby stars.
Also, the solar system's motion could change due to the merger. If it is near the center of
the resulting galaxy, it may be ejected into a farther orbit, affecting its stability and
planet formation. On the other hand, if the solar system is in a more peripheral
region of the galaxy, it may experience fewer gravitational disturbances during the merger.
It is also essential to consider that the merger of galaxies could cause a higher rate
of collisions between astronomical objects, such as stars and planets. Although the probability
of a collision affecting the solar system is low, this possibility cannot be completely ruled out,
especially considering the size of the Sun. What will happen to Earth and the other
planets in the solar system? Could a star collide with the Sun?
What will the sky look like with so many new stars?
Will the solar system survive the merger of both galaxies?
And most importantly, What will happen to the Planets, Earth, and human race when the Milky
Way and Andromeda Galaxy merge? If you want to know the answer
to those questions, wait for our next video! And what do you think? Will the solar system
survive the Milky Way and Andromeda merger? Let us know your opinion with your valuable comment!