2、There are two types of Cepheids, called Type I (or classical) Cepheids and Type II Cepheids. Each type has its own period-luminosity relation, as shown on the graph below. 10% 104- W Vir 102- 1...
A particular type II Cepheid variable has a period of 10 days,
and an apparent magnitude of 3.2. What is the distance of that
Cepheid variable? (Refer to the enclosed figure.)
-6 -5 2 -4 -2 0.25 0.63 1.64.0 10.0 25.0 63.1 Period (days) Figure 3.5 Period-Luminosity Relation for Cepheids Harlow Shapley's estimates fitted all Cepheids onto one curve (solid white line), with luminosity increasing for the longer-period variables. Walter Baade divided Cepheids into two classes, Population (solid black line)...
1/ Sirius A has a luminosity of 9.98 x 10^27 W and a surface temperature of about 9400K. What is its radius? A/ r = 7.56 x 10^8 m B/ r = 1.34 x 10^9 m C/ r= 1.26 x 10^13 m D/ r = 7.94 x 10^-14 m 3/ which of the following stellar properties is the most fundamental to a star’s main-sequence and post-main sequence life? A/ temperature B/ mass C/ luminosity D/ radius 4/ Stars Moppit and...