The reason why scientists think that "strong signals" from space are not for aliens

At the end of August, many headlines announced that they had observed the "strong signal from the HD164595 direction" (Japanese version).HD164595 is a star similar to the sun and is located beyond 94 light years.In the Russian Zerentukuskaya RATAN-600 Radio Telescope, astronomers about 4 background noise..A large radiation of 5 times stronger radio waves was detected.They cautested, maybe an alien.You should investigate.

Their presence rides spread among astronomers.Paul Glistar on the website "Centauri Dreams" wrote that it was "one interesting SETI candidate".is.That caused the media storm.

However, astronomers, the "SETI candidate" signal is hardly known more than that it is radio waves.There is no doubt that humanity should spend a while to think about what this signal is.However, on the other hand, there is almost no reason to conclude that this signal is emitted by non -human life at this time.Let's explain why.

1: I don't know if it came from the star

Veteran's astronomer Seth Shostaku, the director of the SETI Research Institute, says that he cannot see the details of the sky using a telescope.Any telescope has a "view".

Ratan's field of view is not circular.This captured the extended range in the east -west direction, and in this case it was mainly HD164595.However, in the north -south direction (radio waves), Shostaku wrote on a research institute website.And the source of the mysterious radio waves can be everywhere in the extension.The "field of view" of a telescope is just a specific pixel.

We tend to think of pixels as a small point that focuses somewhere.However, pixels originally represent the total amount of light in a specific area.The radio wave from the "HD164595 direction" may be slightly north of the actual position of the star, or may have come from the south.Scientists cannot tell the difference.

2: I don't know if it's a "narrow band signal"

Historically, the SETI plan has explored a narrow band signal of the frequency.Scientists, for example, we think that we need technology to compress signals, for example, as we are broadcasting on the radio (the narrowest radio signal in nature is about 300 Hz).

In other words, the compressed signal is considered to be "someone intentionally".Therefore, SETI scientists collect radio waves from the sky, divide them into multiple frequencies, and find out if there is one or a few bandwidth.Allen Terescope Array of the SETI Research Institute divides the signal into a lump of Hertz width, which is 100 billion times finer than the Gigahertz width Ratan-600 data.

However, the telescope uses the frequency of one gigahertz.Was the original signal a narrow band?Is it a wide band?This data alone is not known.

3: I don't know if it's "interference created by humans"

Astronomers don't know if the signal is compressed or spread, but knows the central frequencies that the telescope is most likely to detect.About 11 Gigahertz.

The radio telescope captures attractive radio waves from space.However, radio telescopes also capture radio waves that are not so attractive from the earth or from the global orbital.Airport radar, Wi-Fi, mobile phone.And what moves with electricity basically emits radio waves.