Constraining the deep interior structure of the Moon

22/07/21 14:12
moon_interior


Planetary interior structure models suffer from an inherent non-uniqueness. However, it is possible to better constrain parameters governing the interior structure using available observational constraints. For the Moon, these constraints are derived from seismic measurements, lunar laser ranging, and magnetic and gravity observations. Following up on previous suggestions of partial melting at the bottom of the Lunar mantle based on early seismic data analyses, recent studies have argued for the presence of a low rigidity layer between the liquid outer core and the mantle. As a participating scientist with NASA’s GRAIL mission, I constrained the interior structure by solving the inverse problem using the observed mass, moment of inertia, and Love numbers. The work provides rigorous measures of uncertainty and resolving power, and indicates that a low rigidity layer between the liquid outer core and mantle is not favored by current observations.

Relevant publications:
  • Matsuyama, I., Nimmo, F., Keane, J. T., Chan, N. H., Taylor, G. J., et al. (2016). GRAIL, LLR, and LOLA constraints on the interior structure of the Moon. Geophysical Research Letters, 1–11. http://doi.org/10.1002/2016GL069952
library(scholar) library(tidyverse) library(glue) # escape some special chars, german umlauts, ... char2html <- function(x){ dictionary <- data.frame( symbol = c("ä","ö","ü","Ä", "Ö", "Ü", "ß"), html = c("ä","ö", "ü","Ä", "Ö", "Ü","ß")) for(i in 1:dim(dictionary)[1]){ x <- gsub(dictionary$symbol[i],dictionary$html[i],x) } x } # my google scholar user id from my profile url # https://scholar.google.com/citations?user=b8bWNkUAAAAJ&hl=en thackl <- "b8bWNkUAAAAJ" # pull from google html_1 <- get_publications(thackl) # convert to htlm table - the ugly way ;) html_2 <- html_1 %>% as_tibble %>% arrange(desc(year)) %>% mutate( # author=str_replace_all(author, " (\\S) ", "\\1 "), author=str_replace_all(author, "([A-Z]) ([A-Z]) ", "\\1\\2 "), author=str_replace_all(author, ", \\.\\.\\.", " et al."), author=str_replace_all(author, "T Hackl", "T Hackl") # make my name fat ) %>% split(.$year) %>% map(function(x){ x <- x %>% glue_data('{author} ({year}) {title}, {journal}, {number}') %>% str_replace_all("(, )+

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Last updated ', format(Sys.Date(), format="%B %d, %Y"), '– Pulled automatically from my Google Scholar profile. See this post for how it works.

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