Exoplanet Watch

  • What is Exoplanet Watch?

    Exoplanet Watch is a citizen science project to observe transiting exoplanets, or planets outside our solar system, with small telescopes. A transiting exoplanet is one that periodically passes in front of its host star, causing the star to slightly dim (by about 1%). Observing exoplanet transits is important, as they allow us to directly measure a planet's radius and composition. Exoplanet Watch will help increase the efficiency of exoplanet studies by large telescopes by reducing uncertainty about the predicted timing of transit events.

  • How many exoplanets are in our galaxy? How many have we found?

    Potentially hundreds of billions, or even more! We’ve found a few thousand so far.

  • How do we find exoplanets?

    There are many ways to find an exoplanet, but most have been found with the transit method. By participating in Exoplanet Watch, you can use small telescopes to help make your own transit observations!

  • What’s a transit?

    When a planet passes between its star and an observer, this is called a transit. These events can be detected as a slight dimming of the star's light as the planet is transiting across the face of the star. Transits of the Moon, Venus and Mercury across the Sun can be directly seen from Earth.

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  • Why should I participate in Exoplanet Watch?

    Exoplanet Watch is a citizen science project that will help keep predicted upcoming exoplanet transit times precise. It's exciting to contribute to the global body of knowledge about planets that orbit stars beyond our solar system! The measurements you make will help scientists use large telescopes, such as Hubble, James Webb Space Telescope, Wide Field Infrared Space Telescope (Nancy Grace Roman Space Telescope), and ARIEL, more efficiently when they observe a transit to characterize an exoplanet’s atmosphere. Your observations of transiting exoplanets will help Exoplanet Watch to keep these predicted times “fresh,” and therefore you will directly help current and future NASA missions! Also, if any of your observations or light curves are included in a publication, you will be listed as a co-author. 

  • How can I get involved?

    If you have your own telescope, you can make your own transit observations and reduce them with EXOTIC to make your own light curves. You can find suggested targets here and reduce them using  Exoplanet Watch’s official software, EXOTIC. If you do not have your own telescope or transiting exoplanet data, use our data checkout system to request some archival data for you to reduce yourself. You will have one week to process the data that is assigned to you.

  • What should I observe?

    Exoplanet Watch posts high-priority targets, here — these targets are those likely to observed with current and future large missions, like Hubble, the James Webb Space Telescope, the Nancy Grace Roman Space Telescope (WFIRST), and ARIEL. While these targets have been determined to be ideal for small telescopes, you are welcome to observe any stars you want to on any given night.

  • How do I observe?

    You can find observation and data-collection guides on the AAVSO website, here and here. Dennis Conti, the Lead of the AAVSO’s Exoplanet Section, has made a useful exoplanet observing guide that can be accessed here.

  • How do I share my light curve with Exoplanet Watch?

    You can upload your light curve to the AAVSO’s Exoplanet Database. The first time you do this, you will first need to register for a free account on the AAVSO website and then apply for an Observer Code that will anonymously associate you with your data. You may also need to include details about the telescope that was used to make the observations. Include your Observer Code when creating your light curves, so that you will get credit for your work.

  • How can I stay connected?

    You can sign up for our monthly newsletter on our email list to get the  latest news, updates, and monthly observing targets. We also have an active Slack, where participants can ask questions, mentor each other, meet other team members, and collaborate. Click on the purple "Slack" link on the sidebar of our website to join or log into our Slack. From there, join channels that interest you.

  • What is EXOTIC?

    EXOTIC, the EXOplanet Transit Interpretation Code, is free software that turns observations of transiting exoplanets into scientific-grade lightcurves. You can find EXOTIC here. There's a tutorial for beginners, a standard online platform-independent version that you can use with data observed by someone else's telescope, and an advanced version for people who use their own telescopes to observe transiting exoplanets.

  • How do I cite Exoplanet Watch and/or EXOTIC?

    Please cite the papers Zellem et al. 2020 and Pearson et al. 2022.

  • I'm using Exoplanet Watch data in my publication — what next?

    If you use any Exoplanet Watch data in your publication, you are required to include the observers and processors of those data as co-authors on your paper. To get in touch with your anonymous observer, contact Dennis Conti, the Lead of the AAVSO’s Exoplanet Section, with their observer code. Please also include the following statement in the acknowledgements section of your paper:

    This publication makes use of data products from Exoplanet Watch, a citizen science project managed by NASA’s Jet Propulsion Laboratory on behalf of NASA’s Universe of Learning. This work is supported by NASA under award number NNX16AC65A to the Space Telescope Science Institute.

  • What is an exoplanet?

    An exoplanet is a planet outside our solar system, usually orbiting another star. They are also sometimes called "extrasolar planets," "extra-" implying that they are outside of our solar system.

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  • What kind of equipment do I need to participate in Exoplanet Watch?

    If you want to observe exoplanets yourself, you will need a telescope (6" or larger), a robotic telescope mount that can track one star across the sky, a camera that can take pictures through the eyepiece of the telescope, a laptop computer, and software to control the telescope.

    If you don't have your own telescope, you can still participate in Exoplanet Watch by requesting data to process with our EXOTIC software.

  • How many exoplanets have Exoplanet Watch citizen scientists studied so far?

    As of December 2022, over 260 different exoplanets have been studied, with over 1,260 light curves. This number updates several times a week, so check out our Results page for the latest metrics.

  • In EXOTIC, I'm having trouble finding the right star in the field of view. What should I do?

    Compare the field of view of your observation with the AAVSO field of view for the same exoplanet. Try to find the x and y coordinates that show where the exoplanet is in your field of view. (x represents how far to the right the star is located in the picture. y is how far up the star is.) If you really can't find it, choose a star you think might be the right one. EXOTIC will give you the coordinates of your target star if you make a mistake, so don't worry about it. It takes time to learn how to recognize a star in a star field. Keep practicing, and it will get easier.

  • What are comparison stars, why do I need them, and how can I find them?

    Comparison stars are stars that are used to compare their steady brightness with the small changes in brightness of the target star as the exoplanet passes in front of it. Comparison stars should not be variable stars (stars that are known to change in brightness) and should be near the target star in the field of view in the observation. Choose one or two comparison stars to compare with the target star. The AAVSO finder chart for each exoplanet identifies comparison stars with numbers associated with them. Use the coordinates of two of the numbered stars in EXOTIC when prompted to enter comp stars.

  • What is a .FITS file?

    .FITS files (Flexible Image Transport System files) are used by astronomers to add metadata about the conditions under which an astronomical observation was made. The header includes information about the location of the telescope, the filter used, and other information.

  • What is a citizen scientist? Do I have to be a citizen of a specific country to participate?

    Citizen scientists are members of the general public who collect and analyze data relating to the natural world as part of a collaborative project with professional scientists. You don't have to be a citizen of a specific country to be able to participate. Everyone is welcome!

  • What't the naming convention for exoplanets?

    Exoplanets are named after the telescope that discovered them. The first exoplanet discovered orbiting its star is named after the host star with the letter "b" following the star's name, so TrES-2 b is the first exoplanet discovered orbiting its host star, TrES 2. WASP-67 b orbits WASP-67, etc. If several exoplanets are discovered at the same time orbiting a star, they will be named from closest to farthest from the star, so TRAPPIST-1 c is the second closest exoplanet discovered orbiting its host star, TRAPPIST-1.

  • Where can I find free software to look at .FITS file?

    The Center for Astrophysics | Harvard & Smithsonian has free software called DS9 that you can download to look at .FITS files: https://sites.google.com/cfa.harvard.edu/saoimageds9 

  • What should I do if I'm not sure my light curve is good enough to upload to the AAVSO?

    You can post a picture of your light curve on our Slack and ask for advice, or just upload it and we'll filter it out if it has any problems.

  • What should I do if I can't see any stars in my field of view when using EXOTIC?

    You may be looking at a cloudy image, or you may be looking at one of the darks instead of a picture that shows the stars. If the data is cloudy, but some frames are clear, you can remove individual cloudy images, and run EXOTIC with the good images. If all of the images are cloudy, you can request another data set. Darks should be moved to a new folder called darks if they haven't already been put in a separate folder when you get the data.It could also be one bad image, which can be erased. Then you can run EXOTIC again and see if that fixed the problem.

  • Where do I find the name of the exoplanet for the data I'm given?

    The name of the exoplaonet can be found in the filename. Check our Results page to see whether your exoplaonet is listed there. It's also in the README file we send you with the data set. The name of the exoplanet is the name of the star it orbits, with the letter b at the end. WASP-49 b orbits the star WASP-49, for example.

  • Who is the main point of contact for Exoplanet Watch?

    Dr. Rob Zellem is the main point of contact for Exoplanet Watch. Email him or reach out to him on Slack if you want him to be a guest speaker at your astronomy club.

  • I have a data set that I requested from Exoplanet Watch, but some of the images are cloudy. Why is that?

    The MicroObservatory observes the night sky every single night of the year, regardless of the weather (the telescope is fully weather-proofed), so occasionally it will take data during cloudy weather. If you cannot see any stars in your images, it could be because the observation was made on a cloudy night. One way to check/confirm is to look at the weather rating of your data, which is listed in the README file that came with your data.

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