Star found 13 billion light-years away

1. Wow. That must be some telescope. But I’m having trouble putting this into some kind of perspective? Star found 13 billion light-years away So am I. Perhaps we need to start a little closer to home.

2. 1 AU = 149 597 871 km. AU, which stands for ‘astronomical unit’, is a unit for measuring distance. One AU is the average distance from the Sun's centre to the Earth's centre. It is equal to 149 597 871 km. Would it be possible to somehow represent these relative distances? For example, if I was the Sun and you were the Earth, how far away would Jupiter have to stand? The distance from the Sun to other planets within our solar system can also be measure in AUs. For example, Saturn is a mean distance of 9.54 AU from the Sun.

3. Light travels at approximately 1 079 253 000 km/hour, and the Earth’s distance from the Sun is 149 597 871 km. Let’s work it out. Since we are talking about such great distances, how long does it take for the Sun’s light to reach Earth?

4. Approximate speed of light = 1 079 253 000 km/hour I now have some idea of the distance planets in our solar system are from one another, but what is a light-year? A light-year is the distance travelled by light in a year. So how far is that?

5. Approximate Speed of Light = 1 079 253 000 km/hour • Approximate distance from the Sun: • Earth = 150 000 000 km • Pluto = 58 790 000 000 km So, am I right in thinking that as this new found star is 13 billion light-years away, this is also the time taken for the light to reach us? That must mean we are looking into the past – almost to the time of the Big Bang! That’s right. Even the closest star to the Sun is 4 light-years away. Worth thinking about when you next look into the night sky. So if I could look at the Earth through a telescope from the Sun, I would be looking approximately 8 minutes into the past.How far into the past would I be looking if stood on Pluto?

6. My own birth England winning the World Cup in 1966 The Great Fire of London in 1666 So how far would I have to travel to look back on Earth and view…

7. Up2d8 mathsSpace, the final frontier Teacher Notes

8. Space, the final frontier Introduction: Through the wonders of science, astronomers have recently discovered a star that is 13 billion light-years from Earth. The light seen from this star is estimated to be around the time the universe was created. The size of our universe can be difficult to comprehend. This Up2d8 puts these distances into context, allowing students to visualise the relative distances involved. Content objectives: • use rounding to make estimates and to give solutions to problems to an appropriate degree of accuracy • express numbers in standard index form, both in conventional notation and on a calculator display • round to a given number of significant figures • rnderstand and use measures of speed. Process objectives: These will depend on the amount of freedom you allow your class with the activity. It might be worth considering how you’re going to deliver the activity and highlighting the processes that this will allow on the diagram below:

9. Activity:Students are introduced to the star story. In order to put such large numbers into context, they initially examine the relative distance between planets within our solar system. They then calculate the time it takes for light to travel from the Sun to Earth and other planets. This will provide some context to how far a light-year is and the distance the recently discovered star is from Earth. Differentiation:You may decide to change the level of challenge for your group. To make the task easier you could consider: • using AU units to visualise the relative distance planets within our solar system are from one another • representing the planets within our solar system on a number line/as a display • researching possible correlations of facts relating to planets within our solar system (eg, size of planet vs distance from Sun) To make the task more complex, you could consider: • calculating the distance light travels over a given time period • the benefits of representing large numbers using Standard Form • why the distance between Earth and the Sun is described as ‘average’. This resource is designed to be adapted to your requirements. Outcomes:The outcome of the task ,may vary depending upon the line of enquiry taken. The students may wish to illustrate their findings diagramatically and/or through calculation. This could be: • displays of the relative distances of the planets within our solar system • presentations to demonstrate the students’ understanding of the quantities and concepts discussed, including findings from research Working in groups: This activity lends itself to paired or small group work and, by encouraging students to work collaboratively, it is likely that you will allow them access to more of the key processes than if they were to work individually. You will need to think about how your class will work on this task. Will they work in pairs, threes or larger groups? If pupils are not used to working in groups in mathematics, you may wish to spend some time talking about their rules and procedures to maximise the effectiveness and engagement of pupils in group work (You may wish to look at the SNS Pedagogy and practice pack Unit 10: Guidance for Groupwork). You may wish to encourage the groups to delegate different areas of responsibility to specific group members. Assessment:You may wish to consider how you will assess the task and how you will record your assessment. This could include developing the assessment criteria with your class. You might choose to focus on the content objectives or on the process objectives. You might decide that this activity lends itself to comment only marking or to student self-assessment. If you decide that the outcome is to be a presentation or a poster, then you may find that this lends itself to peer assessment Probing questions:Initially students could brainstorm issues to consider. You may wish to introduce some points into the discussion that might include: • Why do planets orbit the Sun? • How can the relative distance of planets from the Sun be placed into context? • How are the size of planet, its speed and distance from the Sun related, if at all?

10. Introduction to the star story Calculating a light-year You will need: The PowerPoint display which you might read through with your class to set the scene at the beginning of the activity. There are six slides: Distance between planets in our solar system Is it possible to view the past? Calculating potential time travel! Considering the speed of light