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tokens: in magnetospheric size for the Earth, both with solar rotation and age. We calculate the magnetospheric size considering the Earth's magnetic field to be constant with time (blue solid line) and varying with time according to the model by Zuluaga et al. ( 2013 ; purple dotted line). This model is constrained by magnetic field measurements showing a 50 per cent field strength for a 1 Gyr system estimated by Tarduno et al. ( 2010 ). We can see that both models differ only slightly, with the most significant differences occurring around 1–2 Gyr, showing a spread of just under 1 R M . In particular, we find at early ages, both models predict magnetospheric sizes of ≈ 3 R E . This is understandable, considering the weak dependence on the planetary magnetic field of 1/6, shown in equation ( 23 ). We find a small magnetospheric standoff distance of 3.0 R E for a young Earth 100 Myr old, with the same planetary magnetic field as today ( B p = 0.3 G). These standoff distances would be similar to extreme modern day events, such as the 2003 Halloween storm (Rosenqvist et al. 2005 ), caused by coronal mass ejections (CMEs). However, these transient CME events last only on the scale of hours, but at 100 Myr these magnetosphere sizes would have been typical. Increased solar activity at younger ages (e.g. CMEs) would further compress the young magnetosphere, resulting in even smaller standoff distances. Younger stars are expected to be more active and would be more likely to produce large and more frequent transient events such as CMEs. Figure 4. We observe trends in magnetospheric size with respect to rotation (left-hand panel) and age (right-hand panel). Blue x's: calculated standoff distances with a constant planetary magnetic field of 0.3G. The solar-Earth scenario as it is currently, given as ⊕ . Purple dashed line: This depicts the standoff distances of the magnetosphere if the planetary magnetic field varied according to models described in Zuluaga et al. ( 2013 ). 5 DISCUSSION 5.1 Global properties Since direct observations of mass-loss rate and radio emission from stellar winds are difficult to obtain, we can use models to help understand the physical processes behind these winds. These models can provide information on the strength and location of the wind emission, therefore aiding in observing these winds directly. Recently, there has been research into the mass-loss rates of solar-analogue winds and how they would effect an orbiting planet, including a young Earth. Although some work focuses directly on the Sun–Earth interaction (Sterenborg et al. 2011 ), others focus more on the stellar evolution of these types of stars (Wood et al. 2002 , 2005 , 2014 ; Cranmer Saar 2011 ; Matt et al. 2012 ; Fichtinger et al. 2017 ) and their effects on exoplanets (Vidotto et al. 2012 , 2013 , 2015 ; See et al. 2014 ; Zuluaga, Mason Cuartas-Restrepo 2016 ; See et al. 2017 ). The main basis of our models is the temperature–rotation relation we presented in Fig.