Arushi Nath and Artash Nath The 7th IAA Planetary Defense Conference (26 – 30 April 2021) is hosted by the United Nations Office for Outer Space Affairs (UNOOSA), in cooperation […]
Arushi Nath and Artash Nath
The 7th IAA Planetary Defense Conference (26 – 30 April 2021) is hosted by the United Nations Office for Outer Space Affairs (UNOOSA), in cooperation with the European Space Agency. The biennial conference brings together world experts to discuss the threat to Earth posed by asteroids and comets and actions that might be taken to deflect a threatening object.
We are happy to present our paper: “Aiming for Apophis: How we used COVID-19 School Lockdowns as an Opportunity to Do Asteroid Astrometry” based on our several months of research in Session 12: Public Education & Communication of the 2021 PDC Conference.
How did we get started on Apophis: Drawing Inspiration from the 6th IAA Planetary Defense Conference 2019
Artash was in Grade 7 when he first participated in the 2019 Planetary Defense Conference held in Maryland, Washington DC and presented his work on using Machine Learning to predict the Risk Index (Palermo Technical Impact Hazard Scale) of an Asteroid Colliding with Earth. It won him an Honorable Mention Award. See his presentation and detailed conference report. https://hotpoprobot.com/2019/05/03/learnings-from-the-2019-planetary-defense-conference-poster-presentation-and-simulation-exercise/
During this conference, he heard about asteroid Apophis. NASA had deemed Apophis (discovered in 2004) to be one of the most dangerous asteroids to Earth after its discovery in 2004. Close calls in 2029 and 2036 were predicted and later ruled out. Artash also came back with a 3D printed model of the possible shape of asteriod Apophis. In March 2021, NASA dismissed the threat based on new data and Apophis was removed from the list of dangerous asteroids. However the information and mystery of the asteroid Apophis remained in our minds.
Then COVID-19 lockdowns happened in 2020. Our school doors closed but windows to education and night sky watching remained opened. The 3D printed model of Apophis on our table was a constant reminder of the importance of
planetary defense. It beckoned to us every day to learn more about it and find it in the sky. We accepted the challenge!
Finding a Magnitude 20 Asteroid: Journey around the world in search of robotic telescopes
Apophis was a magnitude 20 asteroid when we decided to find it in the night sky. For comparison, the objects in the sky that we can see with the unaided eye is magnitude 6. This one was 400000 times fainter. Our 8-inch telescope proved no match for it. We needed to look elsewhere, and it was the beginning of the worldwide journey (virtual) in search of a robotic telescope.
We had experiences of handling robotic telescopes by connecting the telescope in our home to the internet. In addition, during our previous visits to the Carr Astronomical Observatory (CAO) in Collingwood, Ontario run by the Royal Astronomical Society of
Canada – Toronto, we had opportunities to handle their telescope digitally. We knew about the software behind these telescopes and the settings we need to input (Right Ascension and Declination) to slew the telescope to the desired objects. We had learned how to determine if the object would be visible from the observatory location, at what time it would appear above the horizon, when would be the best time to view it, and if the object was bright enough to be seen from a telescope of that aperture. We also learned about assessing weather and sky conditions to determine the best seeing window. One of our biggest challenge was to learn about CCD cameras, exposure times, limiting magnitudes and the formats in which CCD images would become available.
Searching for robotics telescopes took us on a trip around the world – virtually. We checked websites of robotic observatories in Australia to those in Canary Islands (Spain), New Mexico and Hawaii (USA), Canada and Chile. We had new respect for infrastructure built around the world by the astronomy community to pursue photons from celestial objects that help us improve our understanding of the universe. We tried out many robotic telescopes including iTelescope.net, Slooh, Telescope.org, MicroObservatory Robotic Telescope Network, Abbey Ridge Observatory, Burke-Gaffney Observatory, and the Faulkes Telescope Project (Les Cumbres Observatory). We did so by writing to them with our proposals and doing follow-ups or signing up for their trial memberships. In some cases, we made use of their heaving discounted prices available for telescope use on nights when the Moon was between three-quarters and full. During this time, these telescopes were more likely to be used by amateur astronomers.
We ended up using a mix of telescopes for our project and successfully captured Asteroid Apophis. These telescopes ranged from aperture sizes of 40cms to 2 meters. It allowed us to become more ambitious with our plans and the asteroids we wanted to image. A big thanks to all the observatories who gave us time on their telescopes and answered our questions.
Observing Plans and Software
Getting access to telescopes is of little use if there are no observing plans. Observation plans need to be queued in advance for these remote telescopes. Creating an observing plan requires knowledge of several supporting software. We used an online version of the Stellarium software to see the position of the Moon in the star field to ensure that objects we image are not too close to the Moon. We used the Telescopius website to get the transit time of the asteroids (the time at which the asteroid would appear at the highest point in the sky for that location), and their Right Ascension (RA) and Declination (DEC) positions. We also got data from the NASA HORIZONS Web-Interface. One of the things we spent a lot of time learning were the celestial coordinates systems which were sometime in degrees, other times in hours, minutes, and seconds, and sometimes as a combination of two.
Python Algorithms for Astrometry
We had previous experience of using Astrometrica software for asteroids detection using data from their Pan-STARRS1 telescope. This meant we knew about the movements of asteroids, and how they would appear in a series of photographs taken over a time interval in the same field of view. Asteroids would appear moving in a straight line while the distant background stars would remain fixed. The process however would be different if the field of view changed.
We became aware of the various formats associated with CCD images such as FITS or the compressed FZ format. We become importance of meta data associated with astrophotography images. The header files in the FITS images contained important information about the images taken as well as telescopes and CCD cameras that imaged them. The header files usually included focal length of the telescope, dimensions of the CCD camera, pixel sizes, filters used, exposure times, time of observation (in UTC) and celestial coordinates to which the telescope was pointed.
Astrometry Education and Outreach to Youths and Citizen Scientists
We believe the best way to learn new things is to think about a challenging project that would require a big learning curve, work on it for a few months to do it well, document what we did and turn it into a training module, and then teach others. The entire project took us almost four months to reach this stage. We did it while attending to our daily online school and other activities.
Making science, data, and technologies accessible to all is essential to encourage participation from youths and let them dream big. Astronomy and planetary defense are no different. Participation of the next generation is imperative as protecting the earth from probable collisions with near Earth objects and its impacts would require inter-generational collaboration. Youths can participate in planetary defense missions in several ways using knowledge they have – ranging from machine learning, animations, simulations, working on big datasets, or willingness to stay curious and ask questions. Internet, You Tube videos, Stack Overflow and GitHub have emerged as avenues to flatten the learning curve and make learning curiosity driven. Motivation and opportunities are still needed so youths, irrespective of their ages and backgrounds are supported.
As with all our projects we have created an online tutorial using Jupyter Notebook. The tutorial is available on our GitHub account (http://www.github.com/Artash-N) and is work in progress. It has allowed other youths to learn from our project and access our code. We have reached out to other youths and citizen scientists by delivering presentations at the monthly meeting of the Royal Astronomical Society of Canada, Toronto and answering questions. We have also presented this project in the Global Innovation Field Trip (GIFT) and even in our respective schools.
Read about our entire journey: