January 12 

12 January 1907

Sergei Korolev

Sergei Pavlovich Korolev (Russian: Сергей Павлович Королёв), the Chief Designer of the Soviet space program in the Experimental Design Bureau  No.1 (OKB-1), was born on January 12, 1907 (New Style), in Zhytomyr, the Russian Empire (now in Ukraine). He led the development of the world's first ballistic missile R-7, the R-7 derived family of launch vehicles, science, military and communications satellites, interplanetary probes and manned spacecraft. His identity was not made public until after his death in 1966. 

   Korolev was trained in aeronautical engineering at the Kiev Polytechnic Institute and then at the Bauman Moscow Higher Technical School, graduating in 1929. In 1931 he joined the Central Aero and Hydrodynamics Institute (TsAGI). In July 1932, Korolev was appointed chief of Jet Propulsion Research Group, GIRD, one of the earliest state-sponsored centers for rocket development in the USSR. In 1933, the military, seeing the potential of rockets, replaced GIRD with the Reactive Propulsion Scientific Research Institute (RNII), where he was appointed deputy head. Korolev supervised development of cruise missiles and a crewed rocket-powered glider.

   In June 1938, at the height of Stalin's purges, Korolev was arrested and sent to concentration camps in Siberia. He first spent months in transit on the Transsiberian railway and on a prison vessel at Magadan. This was followed by a year in the Kolyma gold mines, the most dreaded part of the Gulag. Stalin soon recognized the importance of aeronautical engineers in preparing for the impending war with Hitler, however, and retrieved from incarceration Korolev and other technical personnel that could help the Red Army by developing new weapons. A system of sharashkas (prison design bureaus) was set up to exploit the jailed talent. In September 1940, Korolev was saved by the intervention of senior aircraft designer Andrei Tupolev (1888–1972), himself a prisoner, who requested his services in the TsKB-39 sharashka.

   In July 1944, the authorities paroled Korolev and in September 1945, he traveled to Germany for evaluation and restoration of A-4 ballistic missiles (V-2 rockets). In August 1946, Korolev was appointed chief of a department in the newly created NII-88 in Podlipki, in the suburbs of Moscow. This organization was made responsible for the development and industrial production of missile technology based on German hardware. The first Soviet tests of V-2 rockets took place in October 1947 at Kapustin Yar, with Korolev as management lead for the project. In April 1953, Korolev received approval from the Council of Ministers for development of the world's first intercontinental ballistic missile, the R-7. The first successful flight of R-7 took place on August 21, 1957. A variant of the R-7 missile launched Sputnik 1, the world’s first artificial satellite, on October 4, 1957.

   In the following years, Korolev led the development of several generations of ballistic missiles, launch vehicles, science, military and communications satellites, interplanetary probes and manned spacecraft. During the early 1960s, Korolev campaigned to send a Soviet cosmonaut to the Moon. Following the initial reconnaissance of the Moon by Luna 1, Luna 2, and Luna 3, Korolev established three largely independent efforts aimed at achieving a Soviet lunar landing before the Americans. The first objective, met by Vostok and Voskhod, was to prove that human space flight was possible. The second objective was to develop lunar vehicles which would soft-land on the Moon's surface to insure that a cosmonaut would not sink into the dust accumulated by four billion years of meteorite impacts. The third objective, and the most difficult to achieve, was to develop a huge booster to send cosmonauts to the Moon. His design bureau began work on the N-1 launch vehicle, a counterpart to the American Saturn V, beginning in 1962. Although the project continued until 1971 before cancellation, the N-1 never made a successful flight. On January 14, 1966 Sergei Korolev died in Moscow from a botched abdominal operation.

Korolev with Yuri Gagarin

© 2026, Andrew Mirecki

12 January 1910

The Great January Comet of 1910. Credit: Carl Lampland, Lowell Observatory, Arizona, January 29, 1910

On January 12, 1910, the Great January Comet of 1910 (C/1910 A1), popularly called "The Daylight Comet", was discovered by multiple observers. The comet reached perihelion of 0.129 au on January 17, peaking at a brightness of magnitude -4 to -5, and was plainly visible to the unaided eye during broad daylight.

   The comet came to solar conjunction about 1 degree from the Sun on December 17, 1909 but was still about 1 au from the Sun. In January the comet brightened rather suddenly, and was initially visible from the Southern Hemisphere only. A number of individuals claimed "discovery", but the comet is thought to have been first spotted by diamond miners in the Transvaal before dawn on January 12, 1910, by which time it was already a prominent naked-eye object of apparent magnitude −1.0.

   The first person to study the comet properly was Scottish astronomer Robert T. A. Innes (1861–1933) at the Transvaal Observatory in Johannesburg on January 17, after having been alerted two days earlier by the editor of a Johannesburg newspaper.

   The comet reached perihelion on January 17, and was at that time visible in daylight with the unaided eye, having a magnitude of −5.0, brighter than Venus, due to the forward scattering of light. It came to solar conjunction a second time on January 18, 1910. Following perihelion, it declined in brightness but became a spectacular sight from the Northern Hemisphere in the evening twilight, its noticeably curved tail reaching up to 50 degrees by early February. The comet was last observed as a very faint stain in the background sky on July 9, when probably no brighter than 14th magnitude.

Comet C/1910 A1. Credit: unknown author in Stockholm on January 28, 1910

© 2026, Andrew Mirecki

12 January 2005

Artist's concept of Deep Impact's encounter with comet 9P/Tempel. Credit: NASA/JPL-Caltech/UMD/Pat Rawlings

Deep Impact spacecraft was launched on January 12, 2005, at 18:47:08 UTC on a Delta II rocket. The spacecraft deployed an impactor probe that collided with comet 9P/Tempel, on July 4, 2005. The main spacecraft continued an extended mission, designated EPOXI, and flew by the nucleus of comet 103P/Hartley (or Hartley 2), on November 4, 2010. The last communication with the spacecraft was on August 8, 2013, and was lost some time between August 11 and August 14, 2013.

   The spacecraft consists of a 370 kg cylindrical copper impactor attached to a 650 kg flyby bus. The spacecraft is a box-shaped honeycomb aluminum framework with a flat rectangular Whipple debris shield mounted on one side to protect components during comet close approach. Body mounted on the framework are one high- and one medium-resolution instrument, each of which consists of an imaging camera and an infrared spectrometer which will be used to observe the ejected ice and dust, much of which will be exposed to space for the first time in over 4 billion years. The medium resolution camera had a field of view (FOV) of 0.587 degrees and a resolution of 7 m/pixel at 700 km distance and was used for navigation and context images. The high resolution camera had a FOV of 0.118 degrees and a resolution of 1.4 m/pixel at 700 km. The infrared spectrometers cover the range from 1.05 to 4.8 micrometers with FOV of 0.29 degrees (hi-res) and 1.45 degrees (lo-res). The total flyby bus instrument payload has a mass of 90 kg and used an average of 92 W during encounter.

The Deep Impact spacecraft waits inside the mobile service tower on Launch Pad 17-B, Cape Canaveral Air force Station, for fairing installation. Credit: NASA

   The flyby spacecraft measures approximately 3.2 m x 1.7 m x 2.3 m, was three-axis stabilized and uses a blowdown hydrazine primary propulsion system with 5000 N-s RCS total impulse providing a total delta-V of 190 m/s. Communications with the ground from the flyby bus were via X-band (8.000 MHz) through a 1 meter diameter parabolic dish antenna mounted on a 2-axis gimbal or through a fixed low-gain antenna. Communication between the impactor and flyby spacecraft was in S-band. The uplink data rate was 125 bps, downlink was at 175 kbps. Power of 620 W at the encounter was provided by a 7.2 square meter solar array and stored in a small NiH2 battery. The spacecraft control system consisted of four hemispherical resonator gyros, two star trackers, reaction wheels, and hydrazine thrusters. Pointing accuracy was 200 microradians with 65 microradian knowledge. Thermal control was achieved by insulating blankets, surface radiators, finishes, and heaters. The spacecraft had two redundant RAD750 computers with 309 MB each of memory for scientific data. 

   The impactor projectile was made of primarily copper (49%) and only 24% aluminum so it was easily identifiable and minimized contamination in the spectra after the projectile was largely vaporized and mixed in with the comet ejecta on impact. The impactor was a short hexagonal cylinder built above the copper cratering mass. It had a small hydrazine propulsion system for targeting which can provide delta-V of 25 m/s. Targeting was accomplished using a high-precision star-tracker, auto-navigation algorithms, and the Impactor Targeting Sensor (ITS), a camera which provided images for autonomous control and targeting. The ITS operated until impact, and images were sent back to Earth via the flyby spacecraft.

Deep Impact prior to launch on a Delta II rocket. Credit: NASA

Comet 9P/Tempel 67 seconds after it collided with the impactor, taken by the high-resolution camera on the flyby spacecraft. Credit: NASA/JPL-Caltech/UMD

© 2026, Andrew Mirecki