Editing Very-long-baseline interferometry (section)

== Space VLBI ==
In the quest for even greater angular resolution, dedicated VLBI satellites have been placed in Earth orbit to provide greatly extended baselines. Experiments incorporating such space-borne array elements are termed Space Very Long Baseline Interferometry (SVLBI). The first SVLBI experiment was carried out on [[Salyut-6]] orbital station with KRT-10, a 10-meter radio telescope, which was launched in July 1978.{{citation needed|date=February 2020}}

The first dedicated SVLBI satellite was [[HALCA]], an 8-meter [[radio telescope]], which was launched in February 1997 and made observations until October 2003. Due to the small size of the dish, only very strong radio sources could be observed with SVLBI arrays incorporating it.

Another SVLBI satellite, a 10-meter radio telescope [[Spektr-R]], was launched in July 2011 and made observations until January 2019. It was placed into a highly elliptical orbit, ranging from a perigee of 10,652&nbsp;km to an apogee of 338,541&nbsp;km, making RadioAstron, the SVLBI program incorporating the satellite and ground arrays, the biggest radio interferometer to date. The resolution of the system reached 8 [[microarcsecond]]s.