January 2

2 January 1920

Isaac Asimov

Prolific science fiction writer Isaac Asimov was born in Petrovichi, Russian SFSR, on an unknown date between October 4, 1919, and January 2, 1920, inclusive. He celebrated his birthday on January 2. Asimov was brought to the United States with his family in 1923, and became a US citizen in 1928. He obtained his undergraduate degree from Columbia University in 1939, and took a Doctor of Philosophy degree in chemistry in 1948. In 1949 he joined the Boston University School of Medicine, where he became associate professor of biochemistry. He left the position in 1958 and became a full-time writer.

Asimov was central to science fiction’s Golden Age. Across a prolific career spanning five decades, he produced nearly 500 books, but it is his science fiction — particularly the "Foundation" series and his robot stories — that secured his place in literary history.

Asimov's robot stories, collected primarily in "I, Robot" (1950), "The Caves of Steel" (1954) and "The Naked Sun" (1957), introduced the famous Three Laws of Robotics, a conceptual framework that has influenced not just science fiction but real-world discussions about artificial intelligence and machine ethics. They created a playground for exploring moral paradoxes and the relationship between humanity and its creations. Through detective R. Daneel Olivaw and other mechanical protagonists, Asimov examined what it means to be conscious, ethical, and alive.

Three Laws of Robotics:

First Law
A robot may not injure a human being or, through inaction, allow a human being to come to harm.

Second Law
A robot must obey the orders given it by human beings except where such orders would conflict with the First Law.

Third Law
A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.

— Isaac Asimov
"Runaround" in Astounding Science Fiction (March 1942); later published in "I, Robot" (1950)

Isaac Asimov

The "Foundation" series (short stories and novellas 1942–50, collected in three books 1951–53) showcased Asimov's grandest vision: a galactic empire spanning thousands of worlds and the mathematical science of "psychohistory" that could predict the future of large populations. Inspired by Edward Gibbon's "The Decline and Fall of the Roman Empire", Asimov crafted an epic exploring how civilizations rise, fall, and regenerate. In 1966, the Foundation trilogy won a Hugo Award for the best science-fiction series ever written.

Asimov's science fiction short story "Nightfall" (1941) was voted in 1968 by the Science Fiction Writers of America as the best sf short story of all time. In the time-travel mystery "The End of Eternity" (1955), considered by some critics to be his best work, he demonstrated his ability to weave complex temporal paradoxes into coherent narratives. Under the pen name Paul French, he wrote the "Lucky Starr" series (1952–1958) of juvenile science-fiction novels. "The Gods Themselves" (1972), which won both Hugo and Nebula awards, was a complex tale involving potentially catastrophic energy transfers between alternate universes and depicts alien beings. In the 1980s, Asimov began writing a series of novels in which he ambitiously attempted to combine the "Robot" and "Foundation" series into a single, coherent series.

Best known for his hard science fiction, Asimov also wrote mysteries and fantasy, as well as much nonfiction, including many popular science books. Most of his popular science books explain concepts in a historical way, reaching back as far as possible to a time when the science in question was at its simplest phase of development. Examples include "Guide to Science", the three-volume "Understanding Physics", and "Asimov's Chronology of Science and Discovery". He wrote on numerous other scientific and non-scientific topics, such as chemistry, astronomy, mathematics, history, biblical exegesis, and literary criticism. Asimov died in Manhattan, New York City, on April 6, 1992.

"Predicting the future is a hopeless, thankless task, with ridicule to begin with and, all too often, scorn to end with."

— Isaac Asimov
"The World of 1990" in The Diners' Club Magazine, January 1965

The front cover arts for the "Foundation" trilogy books. Gnome Press first editions (1951–1953)

See also: Jules Verne, Herbert George Wells, Robert A. Heinlein, Arthur C. Clarke

References:

Encyclopedia Britannica: Isaac Asimov
Encyclopedia of Science Fiction: Asimov, Isaac

2 January 1959

Ye-1 lunar probe. Credit: Roscosmos

Soviet Space Rocket (retroactively named Luna 1) was launched on January 2, 1959, with the goal to reach the Moon with an impact probe. Although the probe failed to impact the Moon as planned, Luna 1 became the first spacecraft to achieve escape velocity, fly close by the Moon and enter orbit around the Sun.

   Ye-1 No. 4 was the fourth Soviet spacecraft with the goal to reach the Moon with an impact probe and the first that survived the launch and was put on a trajectory to the Moon. Previous attempts, conducted on September 23, October 11, and December 4, 1958, ended in launch vehicle failures. After the launch the spacecraft with its entire launch vehicle was officially named in the Soviet press as Soviet Space Rocket (Russian: Советская космическая ракета), and unofficially as Mechta (Russian: Мечта, meaning: Dream). The probe was retroactively renamed Luna 1 in 1963.

   The spacecraft was a simple, pressurized spherical object 80 cm in diameter, made from aluminum-magnesium alloy, with several protruding antennas. It was spin stabilized at about one revolution every 14 minutes. The scientific instruments on board were: flux-gate magnetometer, sodium-iodide scintillation counter, two gas discharge Geiger counters, two micrometeorite counters, Cherenkov detector and four ion traps. Two spheres covered by pentagonal medallions were to break up and scatter across the surface on impact. The upper stage of the rocket (Blok Ye) carried additional instruments, including scintillation counter, radio transmitters and one kilogram of sodium to create an artificial comet on the outbound trajectory that could be photographed from Earth. The spacecraft mass (including the power sources installed on the upper stage) was 361.3 kg. With the third stage of the launch vehicle, the total dry mass was 1,472 kg.

   The scientific goals were to detect the magnetic field of the Moon, study the intensity and variation of cosmic rays, record photons in cosmic rays, detect lunar radiation, study the distribution of heavy nucleii in primary cosmic radiation, study the gas component of interplanetary matter, study corpuscular solar radiation, and record the incidence of meteoric particles.

Diagram of Ye-1 probe:
1.- magnetometer; 2. - 183.6 MHz antenna; 3. - micrometeorite counter; 4. - batteries and electronics; 5. - ventilator fan; 6. - spacecraft shell; 7. - ion traps; 8. - ribbon antenna for 19.993 MHz

On January 2, 1959, at 16:41:24 UT, the three-stage 8K72 launch vehicle, derived from the original R-7 rocket that launched Sputnik, lifted the probe from Tyuratam (now the Baikonur Cosmodrome) Site 1/5 in Kazakh S.S.R. It was put on a direct escape trajectory without first entering the Earth orbit. Due to an error in pointing of a ground-based antenna that transmitted guidance information to the launch vehicle, the second stage of the rocket fired longer than intended and imparted extra 41 meters per second in velocity. The velocity relative to the surface of the Earth was 11.34 kilometers per second. According to some sources*, the probe failed to separate after the launch from Blok Ye of the rocket. Despite this Luna 1 was able to operate normally.

On January 3, at 00:57 UT, the attached Blok Ye of the rocket released one kilogram of sodium at about 113,000 kilometers from Earth, producing a glowing orange cloud visible over the Indian Ocean with the brightness of a sixth-magnitude star. It was photographed by Soviet astronomers near Karaganda, although the quality of the images was poor.

The pressurized container of Object Ye-1 (Luna-1 probe) under the head fairing of the third stage of the 8K72 rocket. Credit: Roscosmos

Because of the longer than planned burn of the second stage and excessive velocity, the probe missed the Moon. About 34 hours following launch, on January 4, at 02:59 UT, the spacecraft passed by the Moon at a distance of about 6,400 kilometers (according to various sources from 5,000 to 7,500 kilometers from its surface or its center). Contact with the probe was lost when the batteries run out of power on January 5, around 07:00 UT, approximately 62 hours after launch at a distance 597,000 kilometers from Earth. The probe entered heliocentric orbit with perihelion 0.978 au, aphelion 1.318 au (146.4 by 197.2 million kilometers) and a period of 449.5 days.

Although the probe failed to impact the Moon as planned, Luna 1 became the first spacecraft to achieve escape velocity, fly close by the Moon and enter orbit around the Sun. The measurements obtained by the probe provided new data on the Earth's radiation belt, discovered the solar wind, established that the micrometeoroid flux between Earth and Moon was small and placed an upper limit on the strength of any magnetic field that the Moon may possess at no more than 1/10,000th that of Earth.

* Anatoly Zak. Luna-1: USSR launches the first artificial planet. RussianSpaceWeb.com

Lift-off of the 8K72 rocket with Luna 1 probe on January 2, 1959

Diagram of the heliocentric orbit of Luna 1

Soviet documentary film: "Automatic interplanetary station Luna-1 E-1" on YouTube

2 January 2004

Artist's rendering of the Stardust spacecraft at comet Wild 2 encounter. Credit: NASA/JPL

On January 2, 2004, the Stardust spacecraft, NASA's fourth Discovery mission, flew by the short-period comet 81P/Wild (Wild 2) at a distance of 236.4 ± 1 km, and a velocity of 6.12 km/s. The comet was at a distance of 1.86 au from the Sun, and 98.8 days past its perihelion. The time of the closest approach was determined from the maximum Navigation Camera (NavCam) mirror rotation rate to be January 2, 19:21:32 UTC. The primary goal of the flyby was to collect samples of the coma and return them to Earth in January 2006. All spacecraft systems performed nominally; there were no faults.

Stardust was launched on February 7, 1999, from the Cape Canaveral Air Force Station in Florida, aboard a Delta II 7426 launch vehicle. Its primary goal was to collect dust samples from the coma of 81P/Wild, as well as samples of interstellar dust, and return these to Earth for analysis. En route to Wild 2, the spacecraft also flew by and imaged asteroid (5535) Annefrank. During the mission extension the probe flew by comet 9P/Tempel (Tempel 1) on February 15, 2011.

81P/Wild is a Jupiter family comet. Its nucleus has dimensions 5.5 km × 4.0 km × 3.3 km. Prior to 1974, the comet orbited between a perihelion at 4.9 au and aphelion at 25 au. In September 1974, the comet had a close encounter, within one million kilometers, with Jupiter that dramatically changed its orbit. The comet now has a perihelion distance of 1.58 au, an aphelion near Jupiter's orbit at 5.2 au, and an orbital period of 6.4 years. Since 1974, Wild 2 has made only five perihelion passages before the Stardust flyby. In this sense, Wild 2 is relatively “fresh” comet and its outer layers have only been subjected to moderate solar heating in recent history. Wild 2 probably represents a sample of the Kuiper Belt source region of the solar nebula consisting of mineral, organic and volatile materials of both presolar and nebular origin. The comet was discovered by Swiss astronomer Paul Wild (1925–2014) on January 6, 1978, using a 40-cm Schmidt telescope at Zimmerwald, Switzerland.

The geometry at the closest approach of Stardust to Wild 2; 6.12 km/s is the relative resultant speed of the Stardust spacecraft trajectory with respect to the comet Wild 2. Credit: Tsou, P. et al.

Stardust conducted five science investigations during the Wild 2 encounter:

(1) a sample collection of Wild 2 coma particles,
(2) the measurement of the chemical composition of small grains in the coma,
(3) the recording of the dust impact rates and particle masses with polyvinylidene fluoride films and acoustic sensors,
(4) the NavCam imaging of the Wild 2 coma and nucleus, and
(5) a tracking the Doppler residuals in the radio signal and the spacecraft attitude control sensors to constrain the mass of the comet nucleus and the size of large coma particles.

The spacecraft successfully captured dust samples in its aerogel collector grid, which was then stowed and sealed in the sample return capsule. In addition, 72 images of the comet's nucleus were also taken, revealing surface details with resolutions less than 30 m, and providing substantial information on the comet's size, shape, and surface morphology. The visible landforms were distinctly better resolved than those of comets 1P/Halley and 19P/Borrelly and included craters, excavation zones, flat-floor depressions, surface crusts, landslides, lineaments, terraces, spires/pinnacles (100 m in height), steep cliffs, overhangs, and small bright patches which were potential vents. The nucleus did not have regolith normally associated with asteroids.

The time-of-flight spectrometer registered 29 dust impact mass spectra during flyby and measured the first negative ion mass spectra of cometary particles. The dust detectors recorded particles over a broad mass range, 10⁻¹¹ to 10⁻⁴ g. Unexpectedly, the dust distribution along Stardust's flight path was far from uniform, but instead occurred in short “bursts,” suggesting in-flight breakup of fragments ejected from the nucleus. Longer-exposure images revealed large numbers of jets projected nearly around the entire perimeter of the nucleus, many of which appeared to be highly collimated. A triaxial ellipsoidal fit of the Wild 2 nucleus images yields the principal nucleus radii of 1.65 × 2.00 × 2.75 km (± 0.05 km). The upper limit of the Wild 2 nucleus mass was estimated as 5 × 10¹⁵ kg.

After the flyby Stardust remained on its final 2-year orbit which returned it to Earth on January 15, 2006. Several hours before entry, the sample capsule was ejected from the main spacecraft bus and parachuted down to the Air Force Utah Test and Training Range.

The nucleus of comet Wild 2. This image is the closest short exposure of the comet, taken at an 11.4-degree phase angle, the angle between the camera, comet and the Sun. Credit: NASA/JPL-Caltech

Comet Wild 2 (81P/Wild) nucleus. Credit: NASA/JPL-Caltech

This composite image was taken by the navigation camera during the close approach phase of Stardust's Jan 2, 2004 flyby of comet Wild 2. Several large depressed regions can be seen. To create this image, a short exposure image showing tremendous surface detail was overlain on a long exposure image taken just 10 seconds later showing jets. Together, the images show an intensely active surface, jetting dust and gas streams into space. Credit: NASA/JPL-Caltech

These images taken by NASA's Stardust spacecraft highlight the diverse features that make up the surface of comet Wild 2. Left side shows a variety of small pinnacles and mesas seen on the limb of the comet. Right side shows the location of a 2-kilometer series of aligned scarps, or cliffs, that are best seen in the stereo images. Credit: NASA/JPL-Caltech

See also: Stardust Annefrank flyby, Stardust-NExT Tempel 1 flyby

References:

Tsou, P. et al.: Stardust encounters comet 81P/Wild 2. Journal of Geophysical Research. Planets. December 2004
Bhaskaran, S. et al.: Optical Navigation for the STARDUST Wild 2 Encounter. (pdf). Proceedings of the 18th International Symposium on Space Flight Dynamics (ESA SP-548). 2004

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