State two characteristics of the black-body radiation curve for a typical star, when plotted on axes of intensity against wavelength.
Explain, with reference to the SI units involved, how such a black-body curve can be used to determine the temperature of the star.
Two stars, ADS 1102 A and ADS 1102 B, can be seen very close together in the constellation Taurus. Early astronomers were unsure whether they form a binary system or simply appear in the same line of sight. Table 1 shows some of the properties of the two stars.
Table 1
| Star | Temperature / K | Radius / km | Apparent magnitude |
|---|---|---|---|
| ADS 1102 A | 5600 | 6.4×1056.4 \times 10^56.4×105 | 4.5 |
| ADS 1102 B | 4900 | 5.8×1055.8 \times 10^55.8×105 | 5.3 |
Evaluate whether these data support the suggestion that the two stars form a binary system. In your answer you should:
What is the spectral class of ADS 1102 A?