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Planetary Instrument for X-ray Lithochemistry (PIXL) is a micro-focus X-ray fluorescence spectrometer mounted on the robotic arm of NASA’s Perseverance rover. PIXL will acquire high spatial resolution observations of rock and soil chemistry, rapidly analyzing the elemental chemistry of a target surface. In 10 seconds, PIXL can use its powerful 120 μm-diameter X-ray beam to analyze a single, sand-sized grain with enough sensitivity to detect major and minor rock-forming elements, as well as many trace elements. Over a period of several hours, PIXL can autonomously raster-scan an area of the rock surface and acquire a hyperspectral map comprised of several thousand individual measured points. When correlated to a visual image acquired by PIXL’s camera, these maps reveal the distribution and abundance variations of chemical elements making up the rock, tied accurately to the physical texture and structure of the rock, at a scale comparable to a 10X magnifying geological hand lens. The many thousands of spectra in these postage stamp-sized elemental maps may be analyzed individually or summed together to create a bulk rock analysis, or subsets of spectra may be summed, quantified, analyzed, and compared using PIXLISE data analysis software. This hand lens-scale view of the petrology and geochemistry of materials at the Perseverance landing site will provide a valuable link between the larger, centimeter- to meter-scale observations by Mastcam-Z, RIMFAX and Supercam, and the much smaller (micron-scale) measurements that would be made on returned samples in terrestrial laboratories.

A Correction to this paper has been published: https://doi.org/10.1007/s11214-021-00801-2

Purpose The purpose of this paper is to examine the ways in which stock market valuation and managerial incentives jointly affect merger and acquisition M&A decisions and postM&A performance, and to provide new evidence on the agency implications where such acquisitions are driven by the stock market. Designmethodologyapproach Utilizing all publiclytraded US firms in the NYSE, AMEX and NASDAQ during the period from 1992 to 2005 excluding financial and utility firms, obtained from COMPUSTAT, CRSP, IBES, and the M&A database provided by SDC Platinum, this paper adopts a twostage approach the first stage, predicts the probability of an M&A based on the market valuation variables the second stage, regresses the postM&A firm performance on the predicted probability of a merger or acquisition from the first stage and other control variables. Findings Market valuation has a significant influence on corporate acquisition decisions, particularly for those firms whose compensation packages include less managerial equity ownership, more executive stock options and no longterm incentive plans, and in those firms where CEOs are serving on the board of directors. The valuedestroying acquisitions made by these types of managers are likely to be financed using the firms' stocks, executed with high premiums and undertaken during periods of high market valuation. Originalityvalue The main finding suggests that marketdriven acquisitions could be value destroying when managers engage in opportunistic acquisitions for reasons of selfinterest. Managerial myopia, overconfidence, misaligned incentives, empirebuilding motives and poor corporate governance can all exacerbate the agency problem of marketdriven acquisitions.