Banca de QUALIFICAÇÃO: WILLIAM HUMBERTO ÚSUGA GIRALDO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : WILLIAM HUMBERTO ÚSUGA GIRALDO
DATE: 30/04/2021
TIME: 16:00
LOCAL: https://zoom.us/j/5435517313
TITLE:

Mask technique for detecting space debris with ground telescope images acquired in static mode

KEY WORDS:

Mask; CCD images; detecting;  space debris; telescope; astronomy

PAGES: 50
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUBÁREA: Áreas Clássicas de Fenomenologia e suas Aplicações
SUMMARY:

Orbital debris of approximately 10 cm in size can be measured with ground-based telescopes. This debris threatens the functioning of satellites and has an impact on the economy and the global security of space activities. In the GEO orbit, where most of the economically active satellites are located, exists approximately 842 cataloged debris. On the other side, orbiting LEO exists approximately 13485 debris cataloged. In this context, the  ESA studies show that hundreds of millions of small objects over 1 mm are currently in the two orbits GEO and LEO above the Earth and have not yet been cataloged. In this study, we created a computational procedure to detect space debris in GEO orbit based on images obtained from ground-based telescopes on the static mode. In this mode,  the field sky stars appear as lines in the CCD images and the garbage in the form of dots.  CCD images of 2992 x 2092 pixels (high resolution) and with 5 degrees of field of view (FOV) and with 7 seconds of exposure used in this work were obtained with the PanEOS telescope (Panoramic Electro-Optical System), 750 mm aperture, and installed at the Picos dos Dias observatory of the National Astrophysics Laboratory (LNA). For this research, we adapted the Photoutils package written in Python to build a mask and separate stars from candidates for space debris. Our methodology consisted of first smoothing the images using a Gaussian Kernel filter, then each element was categorized into two categories, and finally, the stars were erased resulting only in space debris candidates. We tested combinations of flow to establish the detection limit and used the different points spread function (PSF) to determine the limit of the elongation of objects. Our methodology works with a single image at a time in a fast and efficient way.  This allows us to detect objects with different PSF and therefore requires low hardware capability. Our results in this validation phase identified 100% of the artificial training debris. In the real images of the PanEOS telescope, we detected a few real debris consistent with the  expected size. In the next steps, we must estimate the size of the object and characterize its orbit.

BANKING MEMBERS:
Interno - 4857669 - JEFFERSON SOARES DA COSTA
Presidente - 2496004 - JOSE DIAS DO NASCIMENTO JUNIOR
Externo à Instituição - LEANDRO DE ALMEIDA