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We present highly resolved and sensitive imaging of the five nearby massivespiral galaxies (with rotation velocities $\rm > 300 km s^{-1}$) observed bythe UltraViolet Imaging Telescope onboard India's multi-wavelength astronomysatellite ASTROSAT, along with other archival observations. These massivespirals show a far-ultraviolet star formation rate in the range of $\sim$$\rm1.4$$-$$\rm13.7 M_{\odot} yr^{-1}$ and fall in the `Green Valley' region with aspecific star formation rate within$\sim$$\rm10^{-11.5}$$-$$\rm10^{-10.5}yr^{-1}$. Moreover, the mean starformation rate density of the highly resolved star-forming clumps of theseobjects are in the range $\rm 0.011$$-$$\rm 0.098 M_{\odot} yr^{-1}kpc^{-2}$,signifying localised star formation. From the spectral energy distributions,under the assumption of a delayed star formation model, we show that the starformation of these objects had peaked in the period of $\sim$$\rm0.8$$-$$\rm2.8$ Gyr after the `Big Bang' and the object that hasexperienced the peak sooner after the `Big Bang' show relatively lessstar-forming activity at $\rm\it{z}$$\sim$0 and falls below the main-sequencerelation for a stellar content of $\rm \gtrsim 10^{11} M_{\odot}$. We also showthat these objects accumulated much of their stellar mass in the early periodof evolution with $\sim31$$-$$42$ per cent of the total stellar mass obtainedin a time of $(1/16)$$-$$(1/5)^{\rm th}$ the age of the Universe. We estimatethat these massive objects convert their halo baryons into stars withefficiencies falling between $\sim 7-31$ percent.

Probing star formation in five of the most massive spiral galaxies observed through $\textit{ASTROSAT UltraViolet Imaging Telescope}$