We examine the ability to test the black hole no-hair theorem at the 10% level in this decade using the binary black hole in OJ287. In the test we constrain the value of the dimensionless parameter q that relates the scaled quadrupole moment and spin of the primary black hole: q 2 = -q χ2. At the present we can say that q = 1 ± 0.3 (1σ), in

Context. Stray light caused by scattering on optical surfaces and in the Earth's atmosphere degrades the spatial resolution of observations. Whereas post-facto reconstruction techniques are common for 2D imaging and spectroscopy, similar options for slit-spectrograph data are rarely applied. Aims: We study the contribution of stray light to the two

In this contribution, several aspects of the discovery of the Milky Way hosting a central bar are briefly reviewed, as well as some minimal introduction about the barred galaxies in the local Universe. The bulk of the contribution is however dedicated to the two main lines of thought about the true nature of the Galactic bar: that which argues for

Not Available

Not Available

Not Available