Analysis of the Sun-Earth Lagrangian environment for the New Worlds Observer (NWO)

Analysis of the Sun-Earth Lagrangian environment for the New Worlds Observer (NWO)

Deccia, C.M.A.

Noomen, R. (mentor)

Aerospace Engineering

Space Flight

2017-06-07

Exoplanets have been detected for more than 15 years. In the vast majority of instances, this has been accomplished through indirect observation. Such methods include among others the observation of radial velocity, transit photometry, and timing variations. These techniques allow for the vast majority of exoplanet detections up to date. An example for a very successful detection that has been achieved recently is the TRAPPIST-1 system. Indirect methods like these can provide us with estimates of a planet’s size and orbit for Earth-like planets. Yet, when we would like to detect life outside our Solar System, the fact alone that a planet lies in the habitable zone and that it has the right size is not a guarantee, but an indication of possible habitability. In order to have absolute certainty, a direct analysis of the atmosphere is needed. Direct observations would allow for a first-hand spectroscopy of the atmosphere in order to search for bio-signatures. These bio-signatures are markers created through biological processes and are indicative of life. Such elements include oxygen, ozone, nitrous oxide and methane. In order to allow for direct observations of Earth-like exoplanets, the New Worlds Observer (NWO) has been proposed as part of NASA Innovative Advanced Concepts (NIAC). NWO is a space-based observatory that will search for Earth-like planets that are located in the habitable zone in neighboring stellar systems. NWO consists of two spacecraft: a 4 m aperture-diameter diffraction-limited telescope and an occulter, called Starshade, which is 50 m in diameter. These spacecraft are located thousands of kilometers apart. This thesis discusses an analysis of the behavior of a satellite pair to be used for a preliminary observation campaign design for the NWO mission concept. In this concept, the two NWO spacecraft are positioned in Halo orbits about the Sun-Earth L2 point. This study demonstrates a novel method that may be used to redirect NWO’s observation vector from one star to another using dynamical systems theory, taking advantage of the non-linear dynamics around L2. To analyze the sensitivity of this method variations of the given constraints have been explored and analyzed.

New Worlds Observer
Starshade
Telescope
Exoplanet
Dynamical systems theory
Lagrange
Free drift

http://resolver.tudelft.nl/uuid:b5b2b94b-3982-4457-a56f-51b5b3574f51

2017-06-07

Student theses

master thesis

(c) 2017 Deccia, C.M.A.