The Pluto—Explored! souvenir sheet contains two stamp designs. One shows an artist’s rendering of the New Horizons spacecraft. The other shows the spacecraft’s striking image of Pluto taken near its closest approach. The view — which is color-enhanced to highlight surface texture and composition — is a composite of four images from New Horizons’ Long Range Reconnaissance Imager (LORRI), combined with color data from the imaging instrument, Ralph. It clearly reveals the now-famous, heart-shaped feature that measures about 1,000 miles across at its widest point. The Pluto flyby completes a historic, half-century era of solar system reconnaissance by the United States. After NASA probed every planet out to Neptune between 1962 and 1989, it took another quarter century to reach Pluto. The United States has been the first nation to explore each of the planets. The New Horizons mission to Pluto and the vast region beyond Neptune called the Kuiper Belt is one of the great explorations of history. Views of Our Planets Forever Stamps The planets of our solar system have been viewed with increasing clarity during the modern era of space exploration thanks to the distant voyages of unmanned spacecraft and the development of ever-more powerful telescopes. With this pane of stamps, the U.S. Postal Service showcases some of the more visually compelling full-disk images of the planets obtained during this era. Antonio Alcalá was the project's art director and designer.  Mercury The image of Mercury seen on the stamp pane is one that NASA’s MESSENGER spacecraft captured shortly after entering the planet’s orbit in March 2011. This color image highlights differences—chemical, mineralogical and physical—between the rocks on the planet’s surface. In actuality, Mercury is gray in appearance. MESSENGER circled Mercury thousands of times before completing its mission in April 2015.  Venus Venus, the planet closest to Earth, has been explored many times since NASA’s Mariner 2 completed a flyby in 1962. Most of its surface, however, remained elusive until the 1990s, when NASA’s Magellan spacecraft penetrated the planet’s thick atmosphere and mapped most of the planet’s features using a radar microwave energy sensor. The false color image of Venus shown on the stamp pane was created in 1991 mainly from surface data generated by the Magellan sensor. In actuality, the cloud cover of the planet gives it an off-white appearance. |
GMT+8, 2024-5-20 07:16 , Processed in 0.103149 second(s), 28 queries .
Powered by Discuz! X3.2
© 2001-2013 Comsenz Inc.
