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<p>Previous studies have shown that conjugate auroral features are displaced in the two hemispheres when the interplanetary magnetic field (IMF) has a transverse (<span class="inline-formula"><i>Y</i></span>) component. It has also been shown that a <span class="inline-formula"><i>B</i>_<i>Y</i></span> component is induced in the closed magnetosphere due to the asymmetric loading of magnetic flux in the lobes following asymmetric dayside reconnection when the IMF has a <span class="inline-formula"><i>Y</i></span> component. The magnetic field lines with azimuthally displaced footpoints map into a “banana”-shaped convection cell in one hemisphere and an “orange”-shaped cell in the other. Due to the Parker spiral our system is most often exposed to a <span class="inline-formula"><i>B</i>_<i>Y</i></span>-dominated IMF. The dipole tilt angle, varying between <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M5" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>±</mo><mn mathvariant="normal">34</mn><msup><mi/><mo>∘</mo></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="26pt" height="11pt" class="svg-formula" dspmath="mathimg" md5hash="f39d1fcf109b05cb1d3103540bab5297"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="angeo-36-1577-2018-ie00001.svg" width="26pt" height="11pt" src="angeo-36-1577-2018-ie00001.png"/></svg:svg></span></span>, leads to warping of the plasma sheet and oppositely directed <span class="inline-formula"><i>B</i>_<i>Y</i></span> components in dawn and dusk in the closed magnetosphere. As a result of the Parker spiral and dipole tilt, geospace is asymmetric most of the time. The magnetic storm on 17 August 2001 offers a unique opportunity to study the dynamics of the asymmetric geospace. IMF <span class="inline-formula"><i>B</i>_<i>Y</i></span> was 20–30&thinsp;nT and tilt angle was <span class="inline-formula">23^∘</span>. Auroral imaging revealed conjugate features displaced by 3–4&thinsp;h magnetic local time. The latitudinal width of the dawnside aurora was quite different (up to <span class="inline-formula">6^∘</span>) in the two hemispheres. The auroral observations together with convection patterns derived entirely from measurements indicate dayside, lobe and tail reconnection in the north, but most likely only dayside and tail reconnection in the Southern Hemisphere. Increased tail reconnection during the substorm expansion phase reduces the asymmetry.</p>