Rosetta, the Solar System cornerstone mission of ESA's Horizon 2000 programme, consists of an orbiter and a lander, and is due to arrive at the comet 67P/Churyumov–Gerasimenko in May 2014. Following its 2004 launch, Rosetta carried out a series of planetary fly-bys and gravitational assists. On these close fly-bys of the Earth, measurements were taken by the Visible Infrared Thermal Imaging Spectrometer (VIRTIS). Analysis of these spectra and comparison with spectra acquired by Earth-observing satellites can support the verification of the inflight calibration of Rosetta/VIRTIS. In this paper, measurements taken by VIRTIS in November 2009 are compared with suitable coincident data from Earth-observing instruments (ESA-ENVISAT/AATSR and SCIAMACHY, and EOS-TERRA/MODIS). Radiative transfer simulations using NEMESIS (Irwin et al., 2008) are fit to the fly-by data taken by VIRTIS, using representative atmospheric and surface parameters. VIRTIS measurements correlate 90% with AATSR's, 85–94% with MODIS, and 82–88% with SCIAMACHYs. The VIRTIS spectra are reproducible in the 1–5 μm region, except in the 1.4 μm deep water vapour spectral absorption band in the near-infrared in cases in which the radiance is very low (cloud-free topographies), where VIRTIS consistently registers more radiance than do MODIS and SCIAMACHY. Over these cloud-free regions, VIRTIS registers radiances a factor of 3–10 larger than SCIAMACHY and of 3–8 greater than MODIS. It is speculated that this discrepancy could be due to a spectral light leak originating from reflections from the order-sorting filters above the detector around 1.4 μm.

Analysis of Rosetta/VIRTIS spectra of earth using observations from ENVISAT/AATSR, TERRA/MODIS and ENVISAT/SCIAMACHY, and radiative-transfer simulations / J., Hurley; P. G. J., Irwin; A., Adriani; M., Moriconi; Oliva, Fabrizio; F., Capaccioni; A., Smith; G., Filacchione; F., Tosi; G., Thomas. - In: PLANETARY AND SPACE SCIENCE. - ISSN 0032-0633. - ELETTRONICO. - 90:(2014), pp. 37-59. [10.1016/j.pss.2013.06.012]

Analysis of Rosetta/VIRTIS spectra of earth using observations from ENVISAT/AATSR, TERRA/MODIS and ENVISAT/SCIAMACHY, and radiative-transfer simulations

OLIVA, FABRIZIO;
2014

Abstract

Rosetta, the Solar System cornerstone mission of ESA's Horizon 2000 programme, consists of an orbiter and a lander, and is due to arrive at the comet 67P/Churyumov–Gerasimenko in May 2014. Following its 2004 launch, Rosetta carried out a series of planetary fly-bys and gravitational assists. On these close fly-bys of the Earth, measurements were taken by the Visible Infrared Thermal Imaging Spectrometer (VIRTIS). Analysis of these spectra and comparison with spectra acquired by Earth-observing satellites can support the verification of the inflight calibration of Rosetta/VIRTIS. In this paper, measurements taken by VIRTIS in November 2009 are compared with suitable coincident data from Earth-observing instruments (ESA-ENVISAT/AATSR and SCIAMACHY, and EOS-TERRA/MODIS). Radiative transfer simulations using NEMESIS (Irwin et al., 2008) are fit to the fly-by data taken by VIRTIS, using representative atmospheric and surface parameters. VIRTIS measurements correlate 90% with AATSR's, 85–94% with MODIS, and 82–88% with SCIAMACHYs. The VIRTIS spectra are reproducible in the 1–5 μm region, except in the 1.4 μm deep water vapour spectral absorption band in the near-infrared in cases in which the radiance is very low (cloud-free topographies), where VIRTIS consistently registers more radiance than do MODIS and SCIAMACHY. Over these cloud-free regions, VIRTIS registers radiances a factor of 3–10 larger than SCIAMACHY and of 3–8 greater than MODIS. It is speculated that this discrepancy could be due to a spectral light leak originating from reflections from the order-sorting filters above the detector around 1.4 μm.
2014
Rosetta; trasferimento radiativo; Virtis; cometa; churyumov gerasimenko; calibrazione; spettrometri
01 Pubblicazione su rivista::01a Articolo in rivista
Analysis of Rosetta/VIRTIS spectra of earth using observations from ENVISAT/AATSR, TERRA/MODIS and ENVISAT/SCIAMACHY, and radiative-transfer simulations / J., Hurley; P. G. J., Irwin; A., Adriani; M., Moriconi; Oliva, Fabrizio; F., Capaccioni; A., Smith; G., Filacchione; F., Tosi; G., Thomas. - In: PLANETARY AND SPACE SCIENCE. - ISSN 0032-0633. - ELETTRONICO. - 90:(2014), pp. 37-59. [10.1016/j.pss.2013.06.012]
File allegati a questo prodotto
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/543709
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 6
  • ???jsp.display-item.citation.isi??? 5
social impact