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Data obtained during the early phases of NEAR's orbital mission answered many first-order questions about the global and regional characteristics of asteroid 433 Eros (1). These data confirmed that the [...], On 25 October 2000, the Near Earth Asteroid Rendevous (NEAR)-Shoemaker spacecraft executed a low-altitude flyover of asteroid 433 Eros, making it possible to image the surface at a resolution of about 1 meter per pixel. The images reveal an evolved surface distinguished by an abundance of ejecta blocks, a dearth of small craters, and smooth material infilling some topographic lows. The subdued appearance of craters of different diameters and the variety of blocks and different degrees of their burial suggest that ejecta from several impact events blanketed the region imaged at closest approach and led to the building up of a substantial and complex regolith consisting of fine materials and abundant meter-sized blocks.

The Near Earth Asteroid Rendezvous (NEAR), a Discovery spacecraft launched on 17 February 1996, was designed to carry out the first detailed orbital investigation of an asteroid (1). After a [...], Eros is a very elongated (34 kilometers by 11 kilometers by 11 kilometers) asteroid, most of the surface of which is saturated with craters smaller than 1 kilometer in diameter. The largest crater is 5.5 kilometers across, but there is a 10-kilometer saddle-like depression with attributes of a large degraded crater. Surface lineations, both grooves and ridges, are prominent on Eros; some probably exploit planes of weakness produced by collisions on Eros and/or its parent body. Ejecta blocks (30 to 100 meters across) are abundant but not uniformly distributed over the surface. Albedo variations are restricted to the inner walls of certain craters and may be related to downslope movement of regolith. On scales of 200 meters to 1 kilometer, Eros is more bland in terms of color variations than Gaspra or Ida. Spectra (800 to 2500 nanometers) are consistent with an ordinary chondrite composition for which the measured mean density of 2.67 ± 0.1 grams per cubic centimeter implies internal porosities ranging from about 10 to 30 percent.

Radio science analyses offer one of the few techniques available for probing the internal structure of asteroids. Doppler and range measurements of the orbiting spacecraft, together with optical observations of [...], We determined the mass of asteroid 433 Eros, its lower order gravitational harmonics, and rotation state, using ground-based Doppler and range tracking of the Near Earth Asteroid Rendezvous (NEAR)--Shoemaker spacecraft and images of the asteroid's surface landmarks. The mass of Eros is (6.687 ± 0.003) x [10.sup.18] grams, which, coupled with our volume estimate, implies a bulk density of 2.67 ± 0.03 grams per cubic centimeter. The asteroid appears to have a uniform density distribution. The right ascension and declination of the rotation pole are 11.37 ± 0.05 and 17.22 ± 0.05 degrees, respectively, and at least over the short term, the rotation state of Eros is stable with no measurable free precession of the spin pole. Escape velocities on the surface vary from 3.1 to 17.2 meters per second. The dynamical environment of Eros suggests that it is covered with regolith and that one might expect material transport toward the deepest potential wells in the saddle and 5.5-kilometer crater regions.

Management and care of men with breast cancer is based on that developed for women. Our study reports that men have specific issues regarding certain aspects of their breast cancer experience, including diagnosis, disclosure, support and gender-specific information, and offers suggestions for improved patient care. [ABSTRACT FROM AUTHOR]