Untitled_Artwork 6.png

Ruling out false positives

In this mini-series Kassie and Nora talk about false positives and how we can rule them out! In our case here, false positives are signals that look like planet transit events but are in facts caused by something other than a planet (such as an asteroid or the telescope wobbling). There are lots of false positives in the TESS data so it's important to learn how to rule then out! 

Accompanying python coding notebooks can be found underneath the videos. 

All Colab notebooks can be found here: 

https://drive.google.com/drive/folders/1s88SM7XPPk5BFZDhutN1NEOIyJNOkC0j?usp=sharing

And all Jupyter Notebooks can be found here: 

https://github.com/noraeisner/PH_Coffee_Chat/tree/main/False%20Positive

How do we rule out false positives using the background flux?

In this video Kassie and Nora discuss what false positives are and how we can use the background flux (brightness of the background) to determine whether a signal could be real or not!

Click the logos to open up the Colab notebook or to download the Jupyter notebook. You can use these to follow along with the video.

How do we rule out false positives using target pixel files?

In this video Kassie and Nora discuss two different diagnostics tests that can be used to rule out false positives: the pixel-level-lightcurve plot and the in and out of transit flux comparison. There is a notebook for each of these two tests. 

pixel-level-lightcurve plot
 
in and out of transit flux comparison

Click the logos to open up the Colab notebook or to download the Jupyter notebook. You can use these to follow along with the video.

How do we rule out false positives using centroid motion?

Kassie wasn't able to join us this week so we have Cole Johnston - a researcher who studies stars and how they evolve - jump in for her. He forgets forgot to introduce himself properly in the video so we'll have to ask him to come back and do that in a future episode (hopefully we can also convince him to talk about stars for us). 

In this video Cole and Nora discuss how we can use the centroid position to determine whether something is a false positive! 

 
 
 

How can the nearest neighbor stars tell you about systematics and asteroids?

In this video Cole and Nora look at lightcurves of stars close to the target that we're interested in. Looking at these can help us rule out false positives due to systematics AND they can be used to track asteroids...

Unfortunately there is no notebook to accompany this episode, but the next episode will show you how you can make this plot! 

 

How can I use LATTE to rule out false positives?

This is the final video in this mini series of false positives. Nora and Cole look into using the LATTE tool to make a pdf report that summarises all of the diagnostic plots (and more) in one concise document. You can download and use LATTE yourself! 

Click here to download instructions on how to install LATTE:

Click here for more information on how to interpret the figures:

More information can be found at: https://github.com/noraeisner/LATTE

 

How do odd/even transits help rule out false positives?

In response to some viewer questions, we're continuing our 'ruling out false positives' series and are going to learn about odd/even transits.

Click the logos to open up the Colab notebook or to download the Jupyter notebook. You can use these to follow along with the video.

7 steps to identify a good exoplanet candidate

In today's episode, Kassie and Nora are going to go through the seven steps it takes to find a good exoplanet candidate. If you've watched our other videos these should be familiar to you, but this is the first time we're going through them in order, from start to finish.