Bibcode
Lorenzi, V.; Pinilla-Alonso, N.; Licandro, J.
Bibliographical reference
Astronomy and Astrophysics, Volume 577, id.A86, 6 pp.
Advertised on:
5
2015
Journal
Citations
14
Refereed citations
14
Description
Context. Icy dwarf planets are key for studying the chemical and
physical states of ices in the outer solar system. The study of secular
and rotational variations gives us hints of the processes that
contribute to the evolution of their surface. Aims: The aim of
this work is to search for rotational variability on the surface
composition of the dwarf planet (136472) Makemake Methods: We
observed Makemake in April 2008 with the medium-resolution spectrograph
ISIS, at the William Herschel Telescope (La Palma, Spain) and obtained a
set of spectra in the 0.28-0.52 μm and 0.70-0.95 μm ranges,
covering 82% of its rotational period. For the rotational analysis, we
organized the spectra in four different sets corresponding to different
rotational phases, and after discarding one with low signal to noise, we
analyzed three of them that cover 71% of the surface. For these spectra
we computed the spectral slope and compared the observed spectral bands
of methane ice with reflectances of pure methane ice to search for
shifts of the center of the bands, related to the presence of
CH4/N2 solid solution. Results: All the
spectra have a red color with spectral slopes between 20%/1000 Å
and 32%/1000 Å in accordance with previously reported values. Some
variation in the spectral slope is detected, pointing to the possibility
of a variation in the surface content or the particle size of the solid
organic compound. The absorption bands of methane ice present a shift
toward shorter wavelengths, indicating that methane (at least partially)
is in solid solution with nitrogen. There is no variation within the
errors of the shifts with the wavelength or with the depth of the bands,
so there is no evidence of variation in the CH4/N2
mixing ratio with rotation. By comparing with all the available data in
the literature, no secular compositional variations between 2005 and
2008 is found.
Related projects
Exoplanets and Astrobiology
The search for life in the universe has been driven by recent discoveries of planets around other stars (known as exoplanets), becoming one of the most active fields in modern astrophysics. The growing number of new exoplanets discovered in recent years and the recent advance on the study of their atmospheres are not only providing new valuable
Enric
Pallé Bago
Minor Bodies of the Solar System
This project studies the physical and compositional properties of the so-called minor bodies of the Solar System, that includes asteroids, icy objects, and comets. Of special interest are the trans-neptunian objects (TNOs), including those considered the most distant objects detected so far (Extreme-TNOs or ETNOs); the comets and the comet-asteroid
Julia de
León Cruz