Dimmest stars

 Dimmest stars

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The sun is the brightest and most luminous thing on the planet.

It also has the honor of being the closest star to the earth.

Although it is a low status on the cosmic level.

The Sun is brighter than 85% of the stars in the Milky Way.

The phase which Sun is passing through at this time is called Main Sequence phase.

Most of the stars in the universe are passing through this phase of their life.

The Sun is increasing its brightness by 1% every 10 million years.

With so many stars in the universe, it's not surprising that there are stars that are smaller, brighter, and fainter than the Sun.

For example, BETELGEUSE, which is in the constellation Orion, is 14,000 times brighter than the Sun.

and 61Cygni AB in the Cygnus constellation. It is the faintest star in the sky visible to the naked eye.

Magnitude scale is used to measure the brightness of stars.

It also has two types

1. Apparent magnitude

2. Absolute magnitude

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1. Apparent magnitude: It depends on how bright the star appears from Earth.

This scale does not reflect the true brightness of the star.

Distance and interstellar dust directly affect the brightness of celestial bodies.

2. Absolute Magnitude: This scale measures the brightness of a celestial body at a fixed distance (which is 10 parsecs).

10 parsecs consists of 5.32 light years.

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When amateur astronomers look at the sky, they only focus on how bright one celestial body is compared to another.

That is, they only consider the external intensity

And

Professional astronomers are interested in the true brightness of a star

That is, which of the two objects at the same distance appears brighter

In their view, absolute intensity is more important.

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In this article we are studying stars whose absolute magnitude is less than that of the Sun and which are visible to the naked eye.

The stars whose absolute magnitude is less than that of the Sun are called faint stars

These stars are brown in color and much smaller than a normal star, so they are also called brown dwarfs.

When they are at their hottest, they look reddish-orange

And in a relatively cool condition, they are seen in a magenta color.

Brown dwarfs are also evidence that star formation does not always result in a conventional star.

Since brown dwarfs are not very large (but much larger than a planet), their cores are not hot enough to trigger nuclear fusion. Therefore, they are very difficult to detect even with the most sensitive telescopes.

They are detected in infrared wavelengths

But distinguishing them from other low-mass stars is still a difficult step.

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The honor of the first discovered brown dwarf goes to Glaze 229b.

It was discovered in 1994 and its location in the constellation Lepus was confirmed in 1995.

Luhman 16A is the closest faint star to Earth (5.6 light-years away) of the Luhman 16 system in the constellation Vela.

The faintest known brown dwarf, 2mass jo9393548, is the 5th closest faint star, 17 light-years from Earth.

This star in the constellation Antlia is a million times dimmer than our Sun.

The Milky Way is a billion times fainter than the Sun in the visible spectrum, along with another brown dwarf.

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We can see 9000 stars with an apparent magnitude of 0.6 with the naked eye

The absolute magnitude of our Sun is 83.4, which means that after 10 parsecs, we will be able to see the Sun shining with an apparent magnitude of 83.4.

Interestingly, out of these 9000 stars, only 42 stars have an absolute magnitude less than the Sun.

And a star that is dimmer than the Sun must be very bright or very close to be visible with or without binoculars.

And there are quite a few stars within 10 prisms of Earth

Only 5% of the 9000 stars are within this distance.

Because

The remaining 95% of stars are far from this limit and are still visible, so it is obvious that they are brighter than the Sun.

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The 10 faintest stars in the night sky are those less bright than the Sun in absolute magnitude and brighter than 5.6 in apparent magnitude.

Can be seen with the naked eye

No

Name

Constellation

Coordinates

(RA/Dec)

Magnitude

Significance

1

Epsilon Eridani

Eridanus

03h 32m 56s 09° 27′ 30″

App: 3.7

Abs: 6.2

The third faintest star closest to Earth

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2

61 Cygni AB

Cygnus

21h 06m 55s

+38° 44′ 41″

App: 4.8

Abs: 8.3

The faintest star visible to the naked eye with absolute magnitude

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3

Epsilon Indi

Indus

22h 03m 22s

-56° 47′ 10″

App: 4.8

Abs: 6.9

A faint orange star surrounded by two brown dwarfs that are themselves very dim

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4

Tau Ceti

Cetus

01h 44m 04s -15° 56′ 15″

App: 3.5

Abs: 5.7

The brightest of the dim stars, resembling the Sun in its spectrum

and is less luminous than the Sun in absolute magnitude

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5

85 Pegasi

Pegasus

00h 02m 10s

+27° 04′ 56″

App: 6.4

Abs: 5.3

Very dark and visible to the naked eye in clear weather (free from light and air pollution).

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6

Sigma Draconis

Draco

19h 32m 22s

+69° 39′ 40”

App: 4.7

Abs: 5.9

Despite being less bright than the Sun, it looks surprisingly bright

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7

70 Ophiuchi

Ophiuchus

18h 05m 27s

02° 29′ 00”

App: 6.1

Abs: 5.5

A variable but very faint star visible to the naked eye on a very dark night.

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