Investigation Driving Question

How can we use supernovae to measure distances in space?

Storylines

The storyline process is intended to be student-driven and connect lessons within the unit. The Exploding Stars investigation, including this phenomenon, would fit best into unit storylines geared toward stellar evolution and methods to determine distances in space.

Possible storylines include:

• How do certain types of stars end their lives?
  

• How can supernova be used to measure distances to galaxies?

Instructions for Introducing Phenomenon

Arrange a Driving Question Board

Before class starts, arrange a Driving Question Board (DQB) so it is visible to all students. This can be created using sticky notes or in a digital format (see other resources here). The DQB will eventually include the investigation driving question, “How can a supernova be used to measure distance in space?” Students will be revisiting this DQB throughout the lesson to expand upon their original thoughts and ask questions to better explain the supporting phenomenon. If you have a driving question for the unit or have already created a DQB board, this investigation driving question can be used as a sub-question.

1. Provide students with a copy of the Supernovae Observations Flashcards PDF (see download below). These flashcards are short summaries of a selection of six supernovae that were observed throughout history.
   
2. Provide students with a few minutes to explore the six supernovae individually.
3. After students have individually explored the supernovae, place them with a partner and ask them to record key observations they notice for each supernova. Students should record these notes to refer back to. If students need extra guidance, instruct them to set up a table in their notebooks that includes four columns. The columns should be titled supernova name, duration (or nights visible), description of brightness, etc.
4. Partners should then form a small group with another set of students to compare observations.
5. Next, in their current small groups, ask students to think about what information we can learn by studying these supernovae. These historical events were so amazing/unusual that astronomers returned to study the sites of these explosions with modern-day instruments. Each group should come up with a list to share with the whole class.
6. On a board visible to all, combine the lists of each group into one class list representing the information we think we can learn from supernovae. Example lists will include, the composition of supernovae, the type of star they exploded from, location in space, distance, etc.
7. Explain to students that advances in technology, specifically, Rubin Observatory, will lead to the detection of about 1 million supernovae per year, compared to the few thousand supernovae that have been observed to date. We will gain a wealth of knowledge by studying these supernovae including how stars are formed and distances in space. Ask students what questions they are left wondering regarding how supernovae are used to measure distance in space. Students should generate a list of questions to post on the DQB for all to refer to.
8. Facilitate a whole class discussion about the questions. Begin by identifying and grouping common questions into categories.

9. Revisit the investigation driving question and tell students they will be completing an investigation that will help them answer this driving question along with their generated questions on the DQB.

10. Begin the Exploding Stars Investigation.

After the Investigation - Making Sense of the Phenomenon

1. Discuss the remaining questions on the driving question board as a whole class and provide students with time to share their final response to the driving question, “How can a supernova be used to measure distance in space?” Encourage students to investigate their remaining questions independently.
2. Reflecting on the Supernova flashcards and Exploding Stars investigation, what are some limitations of using supernovae to measure distances in space?
   Answers will vary. Example limitations: you can’t select the location of the supernova (galaxy) you want to use to make the measurement and the detection of these supernovae rely on the targeted fields of a survey or instrument.
   
3. Only a few thousand Type Ia supernovae have been discovered to date. Now, with Rubin Observatory set to discover approximately 1 million supernovae annually, including over 10,000 Type Ia supernovae, do you anticipate that Rubin's findings will address or alter any of these limitations? If so, in what ways?
   Answers will vary based on the response to question 2. Answers will likely describe how Rubin’s repeated wide-field imaging of the entire southern hemisphere will create a large dataset of Type Ia supernovae, providing much more precise distance measurements.