  Peculiar motion of the solar system, determined from the dipole anisotropy in
the Cosmic Microwave Background Radiation (CMBR), has given a velocity $370$ km
s$^{-1}$ along RA$=168^{\circ}$, Dec$=-7^{\circ}$. Subsequent peculiar motion
determinations from the number counts, sky brightness or redshift dipoles
observed in large samples of distant radio galaxies and quasars yielded
peculiar velocities two to ten times larger than CMBR, though in all cases the
directions matched with the CMBR dipole. Here we introduce a novel technique
for determining the peculiar motion from the magnitude-redshift ($m_{\rm B}-z$)
Hubble diagram of Type Ia Supernovae (SN Ia), one of the best standard candles
available. We find a peculiar velocity $1.6\pm 0.5 \times 10^3$ km s$^{-1}$,
larger than the CMBR value roughly by a factor of four, along
RA$=173^{\circ}\pm12^{\circ}$, Dec$=10^{\circ}\pm9^{\circ}$, the direction
being within $\stackrel{<}{_{\sim}}2\sigma$ of the CMBR dipole. Since a genuine
solar motion would not depend upon the method or the dataset employed, large
discrepancies seen among various dipole amplitudes could imply that these
dipoles, including the CMBR one, might not pertain to observer's peculiar
motion. However, a common direction for various dipoles might indicate a
preferred direction in the universe, implying an intrinsic anisotropy, in
violation of the cosmological principle, a cornerstone of the modern cosmology.
