I am interested in whether there are Earth-like planets of other stars and if these have life. While this has been a topic of speculation for thousands of years, only now is the technology becoming available to undertake astronomical observations with enough sensitivity. Neville Woolf and I realized that cold telescopes in space could potentially resolve the thermal emission of terrestrial planets and that greenhouse gases could be detected in relatively crude spectra. We would hope to detect in another planet the strong water and ozone features that in Earth's spectrum are indicators of oceans and life. The kind of telescope needed to make these observations combines the light from several large, lightweight mirrors in space, destructively interfering the stellar emission to reveal the much fainter planet. While such a telescope, first proposed by Ron Bracewell, is still more than a decade off, we have now demonstrated the technique with ground telescopes and will soon use it to study Jupiter-like exoplanets with the large binocular telescope. An even bigger ground-based interferometer now on the drawing boards, combining two 20-m telescopes, could make the first detection of Earth-like planets if they are commonly present around stars like the Sun.