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There is a demand for more STEM professionals. Early elementary students’ conceptions about engineering can influence whether or not they explore STEM career paths and ultimately select an engineering career. This study examined the conceptions elementary students have regarding the work that engineers perform. The research questions were the following: (1) what images do early elementary students associate with engineering and engineers, (2) do these associations vary from grade to grade, (3) are there gendered differences in these associations, and (4) how do the associations from this sample compare with the associations from the broader (grades one–five) Cunningham, Lachapelle, and Lindgren-Steider (2005) sample? Survey data from 1811 students in grades one–three were analyzed by comparison analysis and cluster analysis and then compared to the initial Cunningham et al. (2005) study. The results indicate two ways elementary students envision engineering: (a) creating designs or collecting and analyzing data, and (b) utilizing equipment to build and improve things. Comparison with the Cunningham et al. (2005) study suggests that there may be shifts in the way elementary students perceive engineering. Since these shifts could be attributed to a variety of factors, future work that determines what learning experiences might be contributing to students’ conceptions about engineering is recommended. 

In response to a growing need for STEM professionals, this study reports the results of the initial validation of a refined survey instrument that purports to measure the five constructs of the social cognitive career theory framework within the subjects of mathematics, science, engineering and technology. To investigate the instrument’s reliability and psychometric properties, we administered this 45-item survey to students in grades 4–12. Reliability and validity (content and construct) were assessed using Cronbach’s coefficient alphas and structural equation modeling. Path coefficients for the five constructs indicated weak to moderate influences on the subscales, and the goodness-of-fit indices demonstrated that the model is acceptable. Initial results indicate the survey has the potential to collect reliable and valid data and suggest the instrument may be helpful in measuring students’ interests and choices in STEM careers for research, partnerships, and curricular development. Additionally, results highlight two areas for further investigation, which include the impact conscientious or random responders have on the survey’s psychometric properties and what constitutes satisfactory Cronbach’s alpha for results to be interpreted in a significant way. 

Asteroid Ryugu and Ivuna-type carbonaceous meteorites may have originated from the outskirts of the Solar System. 

The Hamburg meteorite fell on January 16, 2018, near Hamburg, Michigan, after a fireball event widely observed in the U.S. Midwest and in Ontario, Canada. Several fragments fell onto frozen surfaces of lakes and, thanks to weather radar data, were recovered days after the fall. The studied rock fragments show no or little signs of terrestrial weathering. Here, we present the initial results from an international consortium study to describe the fall, characterize the meteorite, and probe the collision history of Hamburg. About 1 kg of recovered meteorites was initially reported. Petrology, mineral chemistry, trace element and organic chemistry, and O and Cr isotopic compositions are characteristic of H4 chondrites. Cosmic ray exposure ages based on cosmogenic³He,²¹Ne, and³⁸Ar are ~12 Ma, and roughly agree with each other. Noble gas data as well as the cosmogenic¹⁰Be concentration point to a small 40–60 cm diameter meteoroid. An⁴⁰Ar‐³⁹Ar age of 4532 ± 24 Ma indicates no major impact event occurring later in its evolutionary history, consistent with data of other H4 chondrites. Microanalyses of phosphates with LA‐ICPMS give an average Pb‐Pb age of 4549 ± 36 Ma. This is in good agreement with the average SIMS Pb‐Pb phosphate age of 4535.3 ± 9.5 Ma and U‐Pb Concordia age of 4535 ± 10 Ma. The weighted average age of 4541.6 ± 9.5 Ma reflects the metamorphic phosphate crystallization age after parent body formation in the early solar system.