hcmcg

 

Dwarf Planets

Ceres

Pluto

Haumea

Makemake

Eris

diameter ( Earth=1 )

0.076

0.180

0.110
(average)

0.102-0.149

0.188-0.235

diameter ( km )

974.6

2,300

1,960 x 1,518 x 996
(ellipsoid)

1,300-1,900

2,400-3,000

mass ( Earth=1 )

0.00016

0.002

0.00070

0.00067

0.0028

mean distance from Sun ( AU )

2.76596

39.44

43.335

45.791

67.6681

orbital period ( Earth years )

4.599

247.7

285.4

309.88

557

orbital eccentricity>

0.07976

0.2482

0.18874

0.159

0.44177

mean orbital velocity ( km/sec )

17.882

4.74

4.484

4.419

3.436

rotation period ( in Earth days )

0.378

-6.38*

0.163

?

> 8 hrs ?

inclination of axis ( degrees )

3

122

?

?

?

mean temperature at surface ( °C )

-106

-220

-223

-240

-230

gravity at equator ( Earth=1 )

0.028

0.06

0.045

0.051

0.082

escape velocity ( km/sec )

0.51

1.27

0.84

0.8

1.31

mean density ( water=1 )

2.077

2.03

2.6-3.3

2

1.18-2.31

atmospheric composition

none

CH4

none?

maybe CH4

maybe CH4

number of moons

0

3

2

0

1

rings?

no

no

no

no

no