Milky Way Galaxy Atlas





Wolf Rayet
Class



53,000 K to 200,000 K
94,940 F to 359,540 F


20 to 74

2 to 25




O
Class



30,000 K to 52,000 K
53,540 F to 93,140 F


16 to 25

6.6 to 10




B
Class



10,000 K to 29,999 K
17,540 F to 53,538 F


2.1 to 15

1.8 to 6.5




A
Class



7,500 K to 9,999 K
13,040 F to 17,538 F


1.4 to 2.1

1.4 to 1.7




F
Class



6,000 K to 7,499 K
10,340 F to 13,038 F


1.04 to 1.3

1.15 to 1.3



G
Class
(Our Sun)



5,200 K to 5,999 K
8,900 F to 10,338 F

10 Million K to 15 Million K
18 Million F to 27 Million F

0.80 to 1.03

0.96 to 1.14




K
Class



3,700 K to 5,199 K
6,200 F to 8,898 F


0.45 to 0.70

0.70 to 0.95




M
Class



2,400 K to 3,699 K
3,860 F to 6,198 F


0.08 to 0.44

0.69 or Less




L
Class



1,300 K to 2,000 K
1,880 F to 1,880 F



51 to 80 Jupiter Masses

Similar to Jupiter




T
Class



700 K to 1,299 K
800 F to 1,878 F


26 to 50 Jupiter Masses

Similar to Jupiter




Y
Class



440 K to 699 K
332 F to 798 F


9 to 25 Jupiter Masses

Similar to Jupiter




Sub BD
Class



225 K to 439 K
-54 F to 330 F


3 to 8 Jupiter Masses

Similar to Jupiter



D
Class
(White Dwarf)

Class D - White Dwarf Star

4,000 K to 150,000 K
6,740 F to 269,540 F

2.5 Million K to 1 Billion K
4.5 Million F to 1.8 Billion F

0.17 to 1.33

8,700 Miles




Neutron Star
Class


600,000 K to 1,000,000 K
1,079,540 F to
1,799,540 F

1 Trillion K
1.8 Trillion F

1.1 to 3.3

12.4 Miles




Black Hole
Class

Black Hole Class

0 K to 2.7 K
-459 F to -454 F

Unknown or
Not Possible

3.8 to 40 Billion

15 to 146.6 Billion Miles









Asteroidan
Class

Asteroidan Class Planet

0.00015 or Less

0.080 or Less

Ceres
No atmosphere
Not Habitable




Plutonian
Class

Plutonian Class Planet

0.00016 to 0.005

0.081 to 0.20

Pluto
Possible atmosphere
Not Habitable




Mercurian
Class

Mercurian Class Planet

0.006 to 0.10

0.21 to 0.49
Possible atmosphere
Not Habitable




Sub Terran
Class

Sub Terran Class Planet

0.11 to 0.50

0.50 to 0.79
Possible atmosphere
Could be Habitable




Terran
Class

Terran Class Planet

0.51 to 1.99

0.80 to 1.29

Venus and Earth
Significant atmosphere
Could be Habitable




Super Terran
Class

Super Terran Class Planet

2.00 to 9.99

1.30 to 2.00
Significant atmosphere
Could be Habitable




Neptunian
Class

Neptunian Class Planet

10.00 to 50.00

2.10 to 4.00
Thick atmosphere
Not Habitable




Jovian
Class

Jovian Class Planet

51.00 to 5,00.00

4.10 to 27.00
Ultra Thick atmosphere
Not Habitable




For a Planet to be considered "Earth-Like", it must meet the following 11 criteria. These criteria in no way indicate that other planets that are not "Earth-like", are not habitable. A planet that
is not "Earth-like" may still be habitable. These rules give us a framework to determine how closely a planet resembles Earth, and thus whether life as we know it could inhabit such a planet.

[Criteria 1] A Planet must be located within the Habitable Zone of its parent star (the area where liquid water has the potential to exist)
[Criteria 2] A Planet must not be tidally locked with its parent star
[Criteria 3] A Planet must not be subjected to strong or intense solar flares from its parent star (flares must be moderate or less)
[Criteria 4] A Planet must be a Terran Size Class
[Criteria 5] A Planet must have a Terran Mass between 51% and 159%
[Criteria 6] A Planet must have an Average Density Range between 3.50 and 7.50
[Criteria 7] A Planet must have a Diameter between 6,334 to 10,214 Miles
[Criteria 8] A Planet must have an Atmospheric Pressure between 80% and 120% that of Earth
[Criteria 9] A Planet must have a breathable atmosphere like Earth
[Criteria 10] A Planet must have an average global temperature between 50 and 100 Degrees Fahrenheit (Warm Climate)
[Criteria 11] A Planet must have liquid water on its surface (given sufficient atmospheric pressure)



Earth Related

Terran Class Planet

0.51 to 0.64

6,334 to 6,729 Miles

3.50 to 3.99

None




Earth Similar

Terran Class Planet

0.65 to 0.79

6,730 to 7,125 Miles

4.00 to 4.49

None




Earth-Like

Terran Class Planet

0.80 to 0.89

7,126 to 7,521 Miles

4.50 to 4.99

None




Earth Analog

Terran Class Planet

0.90 to 0.97

7,522 to 7,839 Miles

5.00 to 5.34

None




Earth Twin

Terran Class Planet

0.98 to 1.02

7,840 to 7,996 Miles

5.35 to 5.65




Earth Analog

Terran Class Planet

1.03 to 1.10

7,997 to 8,314 Miles

5.66 to 6.00

None




Earth-Like

Terran Class Planet

1.11 to 1.20

8,315 to 8,710 Miles

6.01 to 6.50

None




Earth Similar

Terran Class Planet

1.21 to 1.35

8,711 to 9,422 Miles

6.51 to 7.00

None




Earth Related

Terran Class Planet

1.36 to 1.59

9,423 to 10,214 Miles

7.01 to 7.50

None










Inferno
1,201 F +

Inferno Jovian Planet

Inferno Neptunian Planet

Inferno Super Terran Planet

Inferno Terran Planet

Inferno Sub Terran Planet

Inferno Mercurian Planet

Inferno Plutonian Planet



Janssen, Saffar


Extremely Hot
801 F to 1,200 F

Extremely Hot Jovian Planet

Extremely Hot Neptunian Planet

Extremely Hot Super Terran Planet

Extremely Hot Terran Planet

Extremely Hot Sub Terran Planet

Extremely Hot Mercurian Planet

Extremely Hot Plutonian Planet



Venus, 61 Virginis b




Very Hot
401 F to 800 F

Very Hot Jovian Planet

Very Hot Neptunian Planet

Very Hot Super Terran Planet

Very Hot Terran Planet

Very Hot Sub Terran Planet

Very Hot Mercurian Planet

Very Hot Plutonian Planet

Very Hot Asteroidan Planet

Ross 780 b, Thestias




Hot
96 F to 400 F

Hot Jovian Planet

Hot Neptunian Planet

Hot Super Terran Planet

Hot Terran Planet

Hot Sub Terran Planet

Hot Mercurian Planet

Hot Plutonian Planet

Hot Asteroidan Planet

Mercury, Tau Ceti e




Warm
45 F to 95 F

Warm Jovian Planet

Warm Neptunian Planet

Warm Super Terran Planet

Warm Terran Planet

Warm Sub Terran Planet

Warm Mercurian Planet

Warm Plutonian Planet



Earth, Gliese 163 d




Cold
44 F to -200 F

Cold Jovian Planet

Cold Neptunian Planet

Cold Super Terran Planet

Cold Terran Planet

Cold Sub Terran Planet

Cold Mercurian Planet

Cold Plutonian Planet






Freezing
-201 F and Below

Freezing Jovian Planet

Freezing Neptunian Planet

Freezing Super Terran Planet

Freezing Terran Planet

Freezing Sub Terran Planet

Freezing Mercurian Planet




 

 


 





Planet with Moon

Terran Planet with Moon

This planet has one or
more moons orbiting it

A moon can also be
termed a natural satellite

The Moon stabilizes the
Earth's rotation slightly




Planet with Rings

Jovian Planet with Rings

This planet has a
ring system orbiting it

None

Saturn's ring particles are made of water ice and rock





Planet in Habitable Zone

Terran Planet in Habitable Zone
Orbits its star at a distance where it could have liquid
water given it has enough
atmospheric pressure

The Habitable Zone is also
known as the Goldilocks Zone

Earth
The Sun's Habitable Zone
ranges from 0.9504 AU
to 1.6760 AU





Strongly Radiated Planet
in the Habitable Zone

Terran Planet in Habitable Zone
Orbits its star in the habitable
zone, but is bombarded by
strong radiation and flares from
its parent star

NA

None
Solar flares can strip off the atmosphere and
radiate the surface





Intensely Radiated Planet
in the Habitable Zone

Terran Planet in Habitable Zone
Orbits its star in the habitable
zone, but is bombarded by
intense radiation and flares from
its parent star

NA
Solar flares can strip off the atmosphere and
radiate the surface









Astronomical Unit

AU

Average distance from
the Earth to the Sun


93 Million Miles


The distance from the Earth
to the Sun is 1.000 AU



Light Year

LY

The distance that light travels
in One Earth Year


5.88 Trillion Miles


The distance from our Solar System to
Proxima Centauri is 4.2421 LY