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Disertaciones Astronómicas Boletín Número 64 De Efemérides Astronómicas 11 De Febrero De 2021

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Disertaciones Astronómicas Boletín Número 64 De Efemérides Astronómicas 11 De Febrero De 2021 Disertaciones astronómicas Boletín Número 64 de efemérides astronómicas 11 de febrero de 2021 Realiza Luis Fernando Ocampo O. ([email protected]). Noticias de la semana. Histórico de las Misiones a Marte. Imagen 1: Vista del planeta Marte, compuesta por más de 100 imágenes del orbitador Viking. Imagen: NASA La Era Espacial comenzó el 4 de octubre de 1957. En esa fecha, la Unión Soviética utilizó un cohete originalmente destinado a ser utilizado con misiles balísticos, para lanzar el Sputnik 1, una pequeña esfera de metal pulido que pesaba 84 kg. Al llegar a su órbita, se convirtió en el primer satélite artificial de la Tierra. Viajando a cinco millas por segundo, con una altitud que oscilaba entre unas 140 millas en su punto más bajo y 600 millas en su punto más alto, orbitaba la Tierra una vez cada 98 minutos. Fue casi un fracaso. La telemetría después del hecho indicó que un desequilibrio de refuerzo inicial se produjo un segundo después de hacer que el cohete se inclinara tan bajo que se hubiera desviado hacia abajo, provocando que se estrellara cerca del sitio de lanzamiento. En noviembre, los soviéticos siguieron ese lanzamiento exitoso con Sputnik 2, que albergaba a un perro, la primera víctima con vida de la nueva carrera espacial. Imagen 2: Wernher von Braun. Imagen: Wikipedia. Von Braun trabajó en el programa de desarrollo de cohetes de la Alemania Nazi. Ayudó a diseñar y desarrollar el cohete V-2 en Peenemünde durante la Segunda Guerra Mundial. Después de la guerra, fue trasladado en secreto a Estados Unidos, junto con otros 1.600 científicos, ingenieros y técnicos alemanes, como parte de la Operación Paperclip. Trabajó para el Ejército de los Estados Unidos en un programa de misiles balísticos de alcance intermedio y desarrolló los cohetes que lanzaron el primer satélite espacial Explorer 1 de los Estados Unidos Imagen 3: Explorer 1 de Estados Unidos, fue parte de la participación estadounidense en el Año Geofísico Internacional. Imagen NASA. Explorer 1 fue el primer satélite lanzado por Estados Unidos y fue parte de la participación estadounidense en el Año Geofísico Internacional. La misión siguió a los dos primeros satélites el año anterior; Sputnik 1 y 2 de la Unión Soviética, comenzando la Carrera Espacial de la Guerra Fría entre las dos naciones. Desde el primer sobrevuelo exitoso en 1965, cuatro agencias espaciales han logrado llegar a Marte: la NASA, el programa espacial de la antigua Unión Soviética, la Agencia Espacial Europea, la Organización de Investigación Espacial de la India, y ahora los Emiratos Árabes Unidos con la misión HOPE. El último lote de misiones con destino a Marte en febrero de 2021 fueron el rover Perseverance y el helicóptero Ingenuity de la NASA, el orbitador Hope de los Emiratos Árabes Unidos (el primero en ese país) y la misión orbital y aterrizador- rover Tianwen-1 de China (otro intento para China para llegar a Marte). Más adelante, en esta década, diferentes agencias espaciales planean una misión de retorno de muestras desde la luna Fobos y una misión de retorno de muestras desde el mismo Marte. Los primeros intentos de llegar a Marte ocurrieron cerca de los albores de la exploración espacial. Teniendo en cuenta que el primer satélite, el Sputnik de la Unión Soviética, lanzado en 1957, es extraordinario que solo tres años después, el programa espacial de la Unión Soviética buscara extender su alcance a Marte. Más formalmente conocida como la Unión de Repúblicas Socialistas Soviéticas (URSS) en ese momento, la Unión Soviética hizo múltiples intentos en la década de 1960 para llegar al Planeta Rojo, y la NASA pronto la siguió con su nave espacial Mariner 3. Estas primeras misiones no lograron llegar ni siquiera cerca de Marte. La línea de tiempo fue la siguiente: 10 de octubre de 1960: Marsnik 1 / Mars 1M No.1 (URSS) lanzado para un sobrevuelo previsto a Marte. La nave espacial fue destruida durante el lanzamiento y no pudo alcanzar la órbita terrestre. 14 de octubre de 1960: Lanzamiento del Marsnik 2 / Mars 1M No. 2 (URSS), también para un sobrevuelo previsto en Marte. Pero de manera similar a Mars 1M No. 1, la nave espacial explotó durante el lanzamiento y no alcanzó la órbita terrestre. 24 de octubre de 1962: Lanzamiento del Sputnik 22 (URSS) para un sobrevuelo previsto a Marte. El cohete que lanzó la nave espacial tuvo un problema fatal y la nave espacial fue destruida poco después de alcanzar la órbita terrestre. Imagen 4: Misión Mars 1, URSS; año 1962. Imagen: Wikipedia. 1 de noviembre de 1962: Mars 1 (URSS) se lanza para un sobrevuelo planeado a Marte. La nave espacial llegó a la órbita terrestre y más allá. Pero casi cinco meses después, el 21 de marzo de 1963, la nave espacial estaba a 106 millones de kilómetros de la Tierra cuando su radio falló y la comunicación con la nave cesó permanentemente. 4 de noviembre de 1962: Lanzamiento del Sputnik 24 (URSS) para un sobrevuelo previsto a Marte. La nave espacial alcanzó la órbita terrestre, pero tuvo un problema fatal cuando cambió su trayectoria hacia Marte y finalmente volvió a caer a la Tierra, en pedazos. 5 de noviembre de 1964: el Mariner 3 (EE. UU.) Se lanza para un sobrevuelo previsto a Marte. Una hora después del lanzamiento, hubo un problema con los paneles solares. Los equipos de tierra no pudieron solucionar el problema antes de que las baterías de la nave espacial se agotaran y la misión fallara. Si bien esas primeras misiones no alcanzaron su objetivo, el Mariner 4 de la NASA finalmente lo hizo. La nave espacial se lanzó el 28 de noviembre de 1964 y fue la primera en volar por Marte el 14 de julio de 1965. Envió 21 fotos del Planeta Rojo a la Tierra. Dos días después del lanzamiento del Mariner 4, la Unión Soviética volvió a intentarlo con Zond 2. La nave pasó por Marte pero la radio falló y no devolvió ningún dato planetario. Imagen 5: Misión Mariner 7 -7. Imagen: NASA Mariner 6 y 7 fueron el segundo par de misiones a Marte en la serie Mariner de exploración del sistema solar de la NASA en la década de 1960 y principios de la de 1970. Al igual que con los otros Marineros, cada uno se lanzó en un cohete Atlas con un propulsor de etapa superior Agena o Centaur y pesaba menos de media tonelada (sin propulsor de cohete a bordo). En 1969, Mariner 6 y Mariner 7 completaron la primera misión dual a Marte, sobrevolando el ecuador y las regiones polares del sur y analizando la atmósfera y la superficie marcianas con sensores remotos, además de grabar y transmitir cientos de imágenes. Por casualidad, ambos volaron sobre regiones llenas de cráteres y se perdieron tanto los volcanes gigantes del norte como el gran cañón ecuatorial que se descubrió más tarde. Sin embargo, sus imágenes de aproximación mostraron que las características oscuras de la superficie vistas desde la Tierra durante mucho tiempo no eran canales, como se interpretó una vez en el siglo XIX. 27 de marzo de 1969: Lanzamiento de Mars 1969A (URSS), pero fue destruido antes de alcanzar la órbita terrestre. 2 de abril de 1969: Mars 1969B (URSS) falló durante su intento de lanzamiento. 8 de mayo de 1971: el Mariner 8 (EE. UU.) También falló durante su intento de lanzamiento. Imagen 6: Misión Mariner 9. Imagen: NASA La imagen de Marte cambió con la llegada del Mariner 9 de la NASA en noviembre de 1971. La nave espacial, que se lanzó el 30 de mayo de 1971, llegó a Marte cuando todo el planeta se vio envuelto en una tormenta de polvo. Es más, algo misterioso asomaba por encima de las columnas de polvo. Cuando los escombros se asentaron en la superficie, los científicos descubrieron que esas características inusuales eran las cimas de volcanes inactivos. Mariner 9 también descubrió una enorme grieta en la superficie de Marte, más tarde llamada Valles Marineris, en honor a la nave espacial que lo descubrió. Mariner 9 pasó casi un año orbitando el Planeta Rojo y devolvió 7.329 fotos. De las más de 7.000 imágenes que transmitió, algunas de las más significativas fueron las primeras vistas detalladas del volcán más grande del sistema solar (Olympus), un sistema de cañones que empequeñece el Gran Cañón (Valles Marineris), y las lunas marcianas Fobos y Deimos. Imagen 7: Mariner H / I (8 – 9). Imagen: NASA. 21 de julio de 1973: Mars 4 (URSS) se lanzó y luego voló sobre Marte el 10 de febrero de 1974, pero ese no era el plan; estaba destinado a orbitar el planeta, no a seguir. Mars 4 (en ruso: Марс-4), también conocido como 3MS No.52S era una nave espacial soviética destinada a explorar Marte. Una nave espacial 3MS lanzada como parte del programa de Marte, estaba destinada a entrar en órbita alrededor de Marte en 1974. Sin embargo, problemas informáticos impidieron que ocurriera la inserción orbital. 25 de julio de 1973: Mars 5 (URSS) se lanzó y se colocó en órbita alrededor de Marte el 12 de febrero de 1974, pero duró solo unos pocos días. 5 de agosto de 1973: Mars 6 (URSS) se lanzó con un módulo de sobrevuelo y un módulo de aterrizaje que llegó al Planeta Rojo el 3 de marzo de 1974, pero el módulo de aterrizaje fue destruido por el impacto. 9 de agosto de 1973: Mars 7 (URSS) se lanzó de nuevo con un módulo de sobrevuelo y un módulo de aterrizaje, y llegó al Planeta Rojo el 3 de marzo de 1974, pero el módulo de aterrizaje no alcanzó el planeta.
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