DSST Astronomy case studies
DSST Astronomy · Put your knowledge to work in context.
Astronomy is one of the DSST (DANTES Subject Standardized Tests) titles listed by Get College Credit under the Physical Sciences subject area, carrying a recommended credit level of 3 Baccalaureate. It is aimed at people who already know introductory college astronomy and want to convert that knowledge into credit rather than repeat a course - including service members, adult learners, and homeschooled or currently enrolled students. The DSST Astronomy case studies are 5 cases and about 2,617 words.
1A Close Moon Around a Trans-Neptunian Object
An 18-month astrometric campaign detects a moon around a trans-Neptunian object. The moon's projected separation is 2,400 km, and its orbital period is 1.60 days, measured with 5% uncertainty.
577 words, about 3 min2Choosing Binning for a Small-Telescope Survey
A 0.40 m f/10 telescope feeds a 1024×1024 CCD with 6.0 µm pixels. The site's median seeing is 2.5 arcsec FWHM.
536 words, about 3 min3A Martian Crater With Lobate Ejecta
A Mars orbiter returns images of a 60 km diameter impact crater in the southern highlands. The crater has a central peak, terraced inner walls, and an ejecta blanket with lobate, flow-like margins.
520 words, about 3 min4A Cepheid Distance With Patchy Dust
A Cepheid in a nearby spiral galaxy has a period of 30.0 days and an apparent V magnitude of 22.0 ± 0.1. Its color excess is E(B−V) = 0.25 ± 0.05, and you adopt R V = 3.1.
508 words, about 3 min5A Methane Claim Around an Active M Dwarf
A rocky planet with radius 1.3 R E orbits an M3 dwarf every 25 days at an instellation of 0.9 S E. JWST transmission spectroscopy reports methane at 3.6σ, CO2 at 2.1σ, and no detectable O2, with a 1σ upper limit of 10 ppm.
476 words, about 2 min