Space is an infinite expanse of place where no sound can be heard because the lack of the medium required for sound for this space maintains such perpetual silence. But it would be wrong to think that space is a quiet place where nothing is happening because we can't hear it. Something is happening there at every moment and its expression is spreading around everywhere through various signals. One of them is Radio Signal. Radio signal is Electromagnetic waves like light. (Electromagnetic wave: One of the waves that are propagated by simultaneous periodic variation of electric and magnetic field intensity. Example is visible light, radio waves, ultraviolet ray, x-ray, gamma ray etc.)
All
of these radio signals can be either natural or artificial. Natural radio
signals can be generated naturally by comets, satellites, planets, stars or
galaxies. Artificial radio signals can be generated by man-made devices. Today
we are going to talk about some of the radio signals that have come to earth
from outside the solar system and have aroused considerable curiosity in the
minds of scientists as well as the general public. Everyone is excited about
these signals because every one of it is shrouded in mystery.
1. 1. Lost Cosmonaut:
This radio signal is not only mysterious but also one of the most controversial topics in space science. In the sixties, two brothers from Turin of Italy, Achille Battista and Giovanni Battista, who were very enthusiastic about space and amateur radio operators, tried to understand the radio signals coming from space through radio telescopes. They were also quite famous in Italy at that time.
This is how the two brothers heard a strange radio signal while working on 5th May 1961. After recording the signal over and over again, they came to the conclusion that the signal was a danger signal from an endangered female cosmonaut of a secret space mission sent by Russia. It should be noted that at that time there was intense competition between Russia and the United States on all issues. Coincidentally, a Russian spacecraft had crashed when it came in contact with earth's atmosphere at the time of returning from space. Russia still claims that its wrecked spacecraft was unmanned and automatic. Till date it is unknown to us that what the true incident is. But for the sake of argument, if Russian view is to be accepted, there is no doubt that this radio signal is a highly mysterious signal.
2.
Singing Comet:
While
searching for various mysterious radio signals coming to earth, it was seen
that a radio signal was coming from a distant comet. The European Space Agency
had launched Rosetta spacecraft in 2004 for further research. After a journey
of about 470 crore km in a long 10 years, the spacecraft reached the comet 67P
or Churiyamov-Gerasimenko in 2014. After reaching the comet, the spacecraft
observed the comet more deeply and found that the charged particles ware
constantly being released from the comet's surface. As a result of the release
of these particles, this radio signal had been generated and spread around the
comet.
3.
Cosmic Roar:
It
has already been said that radio waves in space is produced not only by humans
but also by stars, galaxies and other cosmic objects. To find out more, NASA
scientists flew a helium gas-filled balloon in July 2006 under the ARCADE
Mission (ARCADE Mission: Absolute Radiometer for Cosmology, Astrophysics &
Diffuse Emission Mission) led by Dr. Allen Kogut. This balloon was fitted with
very fine equipment and sensors. Over time, the balloon rises to a height of
1,20,000 feet, or 36,576 meter, above the surface. The density of the
atmosphere here is extremely low and thin, which greatly reduce the obstacles
and increases the likelihood of space observations. The radio signal which they
received was 6 times stronger than what scientists had expected and it was
beyond the imagination of scientists. The source of this signal is still
unknown. At first, scientists thought the signal was coming from a star or
nebula of neighbor of our solar system. But later scientists realized that it
was never possible for a star or galaxy to produce such a strong and powerful
radio signal. Their guess is that this signal is coming from a source we don't
know about or a source that existed at the time of the formation of this space.
4.
Sound of Black hole:
In
2019, we first saw the black hole image, but two years earlier, on August 17,
2017, scientist Dr. Edward Morgan, a scientist at the Massachusetts Institute
of Technology, received the radio signal, coming from a black hole with the
help of S. Chandrasekhar's named 5,860 kg space telescope, Chandra X-Ray
Observatory, and transformed the radio signals into audible sound waves for the
human ear. Here the intensity of the sound has been made very low to suit our
ears. There is no means of transmitting sound into space. If it had, we would
always have to hear a sound stronger than a thunderbolt.
5.
HD-164595:
HD-164595
is a star located in the Hercules constellation, 92.2 light years away from our
Earth. Probably
a planet, 16 times larger than Earth, is revolving around this star. On 15th
May, 2015, Russia's Ratan-600 telescope of the SETI Project (SETI: Search
for Extraterrestrial Intelligence), operated by NASA since 1984, once
detected a signal from somewhere near the star. In fact, it is a project that
seeks to communicate with the most advanced creatures in space through radio
signals. The signal received here is so strong that if it was sent by an alien
creature, it would be perhaps a few centuries ahead of our human civilization
in terms of technology because the amount of energy and technology needed to
send such a signal is possible only for very advanced civilizations. To date,
it has not been possible to determine the source of the signal, but scientists
have been working tirelessly to locate the signal. We, the people of the world,
have been continuously sending radio signals to that unknown place and various
possible places around it, but to date we have not received any response. We
will have to wait at least a few more centuries for the answer because to cover
the distance from Earth to that possible place by light would take more than 92
years.
6.
Frequency 4462.3:
This radio signal is found through the activities under the 'SETI Project' and is called the second 'Wow signal'. I will discuss this wow signal later. The signal came from TYC-1220-91-1, a star about 100 light-years from Earth. Although that star is older than our Sun and is similar in shape to the Sun. This signal only came to Earth once on 10th October 2010 and lasted only 10 seconds. The signal was named after its frequency, meaning that the signal came at a frequency of 4462.3 MHz. To this day this signal has not come to earth and we have not been able to find out its source.
7.
Fast Radio Bust:
It
is a kind of high-powered radio signal spread over a short period of time. It can
range from a few milliseconds to a few seconds. This signal is so powerful that
scientists estimate that the source of the radio signal is a few million times
more powerful than our Sun. But one thing is for sure, this radio signal is
natural. Scientists think that the explosion of a red giant star (Supernova) or
the collision of two black holes or two neutron stars could be the cause of
such a powerful radio signal. The first such signal was detected in 2007 by a
radio telescope in Perth, Australia. This signal was also received in Canada
and China. More than once, this radio signal has been received by our Earth's
telescope. So perhaps the possible source of this signal has been guessed. This
light signal may have come from somewhere 50 light years away from the edge of
our galaxy, but it is not yet possible to say for sure. Another group of
scientists said the signal came from a highly advanced alien civilization. The
reason for this is that they argue about the types of this radio signal. There
are two types of Fast Radio Burst Signal. In the case of the first type there
are those radio signals that have only come to earth once. In the case of the
second type, there are radio signals that have repeatedly come to earth. It is
very important to mention the second type of radio signal here. Scientists have
seen that this type of signal comes to the earth for a while and then comes
back to the earth with a break at some point and this cycle continues. Such a
signal comes to the earth continue 12 days for few seconds; it comes again with
a break of 4 days and again for 12 days. Scientists have not been able to
explain this phenomenon today, so this signal is a very strange and mysterious radio
signal.
This is another radio signal that was found through the 'SETI' project. This signal was detected in 2003 by the Massive Radio Telescope of Puerto Rico. The telescope searched more than 200 different places in the sky where radio signals had previously been received, hoping to find more radio signals that were more intense and powerful than other radio signals. The frequency of the last signal received was 1420 MHz. It is a normal quality frequency in space through which hydrogen particles can absorb or dissipate energy. Searching for its source, it was found that its source was a place between the constellations of Pieces and Aries and most surprisingly, this area is a Cosmic Void area. Cosmic Void means the place in space where there are no stars or galaxies within a few thousand light-years.
[Please click on the link to learn more about Cosmic Void. https://spacejagat.blogspot.com/2020/02/c-osmicvoid-literal-meaning-of-these.html]
Scientists at the 'SETI project have suggested that it
could be either natural or artificial. If artificial, is it a matter of
wondering if there really are alien intelligent beings and they have found our
existence ?
9.
Wow Signal:
This time I will discuss the most talked about and most famous radio signal from scientists to ordinary people. The 'SETI' project should also be credited for finding this signal. The Big Ear Radio Telescope at Ohio State University in the United States had received the 72-second signal on August 15, 1977. When scientist Dr. Jerry Ehman was analyzing these radio signals, he realized that these intense radio signals are somewhat different from other signals. With excitement, he surrounded the written form of the radio signal with red ink and wrote "Wow" next to it.
Since then, the name of this signal has
become Wow Signal. At first it was thought that the signal was sent from the
earth into space and then reflected from an astronomical object and returned to
the earth. Somebody said that, this signal might had come from a comet. But
later both these theories were proved wrong. However, the source of that signal
had been confirmed to be the region near the Sagittarius constellation. After
that, radio signals were sent from the earth targeting that region many times,
but that signal came only once. Then today 44 years have passed and no response
has ever come back. This is what makes this signal even more mysterious.
There are also other types
of radio signals that have been received on Earth's radio telescopes at various
times. But here are some of the radio signals that have aroused the curiosity
and excitement of scientists and the general public for mystery. In our solar
system, Sun, Jupiter, Saturn, etc. spread the radio signals around, but our
discussion today is not about those radio signals.
Just as we and the
environment around us are made up of all the natural elements and our habitable
earth is a planet of a star and it revolves around that star, so it is natural
for a situation like ours to be formed with a planet from another star in
distant space. It is not uncommon for animals to be there. But the only
question is, should we communicate with those aliens? It is a question that has
no right answer. Some will say yes and some will not. Famous cosmologist and
mathematician Late Dr. Stephen Hawking did not like the subject of contact with
these aliens. According to him, unfamiliar, unknown distant aliens may be more
advanced in nature than us. Human civilization could be destroyed if they came
to this world and tried to occupy the earth.
The debate may continue,
but it is as interesting as it is sensitive. So we have to proceed very
carefully and understandingly in this regard. Our scientific community is well
aware of this. We have to trust them. We believe that whatever they do will be
for the good of human civilization.
