CURE 2017 internship at JPL Rosetta Mission Amateur Data Archive, Photometry of Pluto Using New Horizons Data Mary Abgarian, Los Angeles City College Dr. Bonnie Buratti, Jet Propulsion Laboratory Dr. Padma Yanamandra-Fisher, Space Science Institute Funded By NASA © 2017 Caltech Images: courtesy of NASA unless otherwise noted Projects • Data Archive: Obtaining and preparing amateur astronomers’ data of comet 67P for ESA’s Planetary Science Archive • Data Analysis: Analyzing New Horizons data from the Ralph Instrument (MVIC), and preparing light curves to support a larger research project involving the comparison of Pluto to Titan and Triton Spacecraft vs. Ground-Based Data Ground-Based Observing Campaign Why Ground-Based Data? • Comparison of spacecraft vs. ground-based observations • Comet activity vs Brightness • Coma trail Image Courtesy of Colin Snodgrass THE ROSETTA ORBITER (11 instruments) • Alice- Ultraviolet Imaging Spectrometer • CONSERT- Comet Nucleus Sounding Experiment by Radio wave Transmission • COSIMA- Cometary Secondary Ion Mass Analyser • GIADA- Grain Impact Analyser and Dust Accumulator • MIDAS- Micro-Imaging Dust Analysis System • MIRO- Microwave Instrument for the Rosetta Orbiter • OSIRIS- Optical, Spectroscopic, and Infrared Remote Imaging System • ROSINA- Rosetta Orbiter Spectrometer for Ion and Neutral Analysis • RPC- Rosetta Plasma Consortium • RSI- Radio Science Investigation • VIRTIS- Visible and Infrared Thermal Imaging Spectrometer Rosetta Spacecraft facts: • International mission to a comet • Launched on March 4, 2005 • First spacecraft to orbit comet’s nucleus • First to dispatch a robotic lander (Philae) on a comet • First spacecraft to closely observe a comet near it’s perihelion Additional Facts: • Launch: 2 March 2004 • Arrive at comet: 6 August 2014 • Start global mapping of comet: 10 September 2014 • Lander delivery: 12 November 2014 • Perihelion passage: 13 August 2015 • Mission End: September 2016 67P/Churyumov-Gerasimenko • Size of nucleus: 4.34 km × 2.60 km × 2.12 km • Small lobe: 2.50 km × 2.14 km × 1.64 km • Large lobe: 4.10 km × 3.52 km × 1.63 km • Mass: 10^13 kg • Volume: 18.7 km^3 • Orbital period: 6.45 years • Perihelion distance from Sun: 186 million km (1.243 AU) • Aphelion distance from Sun: 849.7 million km (5.68 AU) • Surface temperature: -93 °C to 53 °C • Year of discovery: 1969 • Discoverers: Klim Churyumov & Svetlana Gerasimenko Data Collection • First step was to contact astronomers via email and invite them to share their data • Email was sent to ~300 astronomers • 30 responded indicating they have observations of 67P they would like to share • Obtained ~40Gb Data through Large File Transfer Protocol • Total of 10,916 FITS images • Used Raffi Shirinian’s program to read the headers of the files and name each file according to it’s date, time, exposure time and filter • Bash Scripts to further automate the process of organizing the data Pluto New Horizons Spacecraft • New Horizons spacecraft made first exploration of Pluto: 14 July 2015 • Closest approach: 13,691km from Pluto’s center • Ralph Instrument (multicolor, pan mapper) and mapping infrared composition spectrometer • LORRI Instrument: long-focal –length panchromatic visible imager • Alice: extreme/far ultraviolet mapping spectrograph • REX: radio science experiments • SWAP: solar wind detector • PEPSSI: high-energy charged particle spectrometer • VSDC: a dust impact detector • Together, these collected over 50 gigabits of data on the Pluto system during closest approach Data Analysis • Worked with MVIC (Multispectral Visible Imaging Camera) FITS images using IRAF and ISIS • Subtracted background and added up pixel values (Data Numbers) • Used JPL’s Horizons ephemeris to gather information on phase angle ( Sun-Target-Observer), Pluto’s longitude, spacecraft’s distance from target • Brightness =(DN x distance^2)/(exp time) Similarity of Pluto’s atmosphere to other Moons • Titan • Triton Side 0 vs. Side 1 Light gain drifted if the output was read through the primary electronics side (known as side 1), while remained stable when read through the backup electronics side (side 0). (Howett et al., 2016) Similarity of Pluto’s atmosphere to other Moons • Titan • Triton Acknowledgements • Dr. Bonnie Burat • Professor Paul McCudden • Dr. Padma Yanamandra-Fisher • Spencer Devins • Bill Adler • Raffi Shirinian This work supported by NSF grant #1460538 to Los Angeles City College Thank you..