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The EDGES collaboration reported the finding of an unexpectedly deepabsorption in the radio background at 78 MHz and interpreted the dip as a firstdetection of redshifted 21-cm from Cosmic Dawn. We have attempted an alternateanalysis, adopting a maximally smooth function approach to model theforeground. A joint fit to the spectrum using such a function together with aflattened absorption profile yields a best fit absorption amplitude of $921 \pm35$ mK. The depth of the 21-cm absorption inferred by the EDGES analysisrequired invoking non-standard cosmology or new physics or new sources atCosmic Dawn and this tension with accepted models is compounded by our analysisthat suggests absorption of greater depth. Alternatively, the measured spectrummay be equally-well fit assuming that there exists a residual unmodeledsystematic sinusoidal feature and we explore this possibility further byexamining for any additional 21-cm signal. The data then favors an absorptionwith Gaussian model parameters of amplitude $133 \pm 60$ mK, best width athalf-power $9 \pm 3$ MHz and center frequency $72.5 \pm 0.8$ MHz. We alsoexamine the consistency of the measured spectrum with plausible redshifted21-cm models: a set of 3 of the 265 profiles in the global 21-cm atlas of Cohenet al. 2017 are favored by the spectrum. We conclude that the EDGES data may beconsistent with standard cosmology and astrophysics, without invoking excessradio backgrounds or baryon-dark matter interactions.

The redshifted 21-cm signal in the EDGES low-band spectrum