Question 17N.3.SL.TZ0.11
| Date | November 2017 | Marks available | [Maximum mark: 8] | Reference code | 17N.3.SL.TZ0.11 |
| Level | SL | Paper | 3 | Time zone | TZ0 |
| Command term | Identify, Outline, Show that | Question number | 11 | Adapted from | N/A |
Two of the brightest objects in the night sky are the planet Jupiter and the star Vega.
The light observed from Jupiter has a similar brightness to that received from Vega.
Identify the mechanism leading stars to produce the light they emit.
[1]
«nuclear» fusion
Do not accept “burning’’
Outline why the light detected from Jupiter and Vega have a similar brightness, according to an observer on Earth.
[2]
brightness depends on luminosity and distance/b =
Vega is much further away but has a larger luminosity
Accept answer in terms of Jupiter for MP2
Vega is found in the constellation Lyra. The stellar parallax angle of Vega is about 0.13 arc sec.
Outline what is meant by a constellation.
[1]
a group of stars forming a pattern on the sky AND not necessarily close in distance to each other
OWTTE
Outline how the stellar parallax angle is measured.
[2]
the star’s position is observed at two times, six months apart, relative to distant stars
parallax angle is half the angle of shift
Answers may be given in diagram form, so allow the marking points if clearly drawn
Show that the distance to Vega from Earth is about 25 ly.
[2]
= 7.7 «pc»
so d = 7.7 x 3.26 = 25.1 «ly»