X-Ray Star Measured By Rocket

Press, Volume CVI, Issue 31085, 14 June 1966, Page 12

X-Ray Star Measured By Rocket

The spectacular space successes like the Surveyor moon landing and the manned Gemini flights tend to crowd out the achievements of the small sounding rockets which are launched in far greater numbers. Last month, for example, eighteen meteorological rockets were launched in three days from Wallops Island rocket range in Virginia, U.S.A., and across the continent at the White Sands missile range in New Mexico a sounding rocket made the most precise measurement yet of a celestial source of X-rays. Dr Ricardo Giacconi, the principal experimenter, has said that initial data from the flight reveals that the size of the X-ray source in the con-

stellation Scorpius cannot exceed 20 seconds of arc. In other words it appears to be smaller than the size of a football two miles away. It can still be a very large object, but if so it must be at a very great distance. This result strengthens the idea that these newly discovered sources of X-rays are members of an entirely new class of celestial objects. So far no visible objects have been associated with any of the ten or so known X-ray objects, but this recent flight should provide sufficiently accurate position data to enable optical and radio astronomers to point their telescopes right at this mysterious object in Scorpius and possibly find what it is.