January 30

30 January 1964

Model of Ranger Block III spacecraft. Credit: NASA/JPL-Caltech

On January 30, 1964, Ranger VI lunar probe, the first in the series of four Ranger Block III spacecraft, was launched. It carried a suite of six TV cameras capable of taking 300 pictures a minute, and was expected to transmit high-resolution photographs of the lunar surface in the last minutes of the flight until the impact. The spacecraft impacted the Moon as planned on February 2, 1964, but a TV power system failure prevented it from transmitting any images of the Moon's surface.

Ranger VI under construction, September 24, 1963. Credit NASA JPL-Caltech

Full Description from NASA Space Science Data Coordinated Archive:

Ranger 6 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. The spacecraft carried six television vidicon cameras, 2 full-scan cameras (channel F, one wide-angle, one narrow-angle) and 4 partial scan cameras (channel P, two wide-angle, two narrow-angle) to accomplish these objectives. The cameras were arranged in two separate chains, or channels, each self-contained with separate power supplies, timers, and transmitters so as to afford the greatest reliability and probability of obtaining high-quality video pictures. No other experiments were carried on the spacecraft. Due to a failure of the camera system no images were returned.

Spacecraft and Subsystems

   Rangers 6, 7, 8, and 9 were the so-called Block 3 versions of the Ranger spacecraft. The spacecraft consisted of a hexagonal aluminum frame base 1.5 m across on which was mounted the propulsion and power units, topped by a truncated conical tower which held the TV cameras. Two solar panel wings, each 73.9 cm wide by 153.7 cm long, extended from opposite edges of the base with a full span of 4.6 m, and a pointable high gain dish antenna was hinge mounted at one of the corners of the base away from the solar panels. A cylindrical quasiomnidirectional antenna was seated on top of the conical tower. The overall height of the spacecraft was 3.6 m, total mass was 381 kg.

   Propulsion for the mid-course trajectory correction was provided by a 224-N thrust monopropellant hydrazine engine with 4 jet-vane vector control. Orientation and attitude control about 3 axes was enabled by 12 nitrogen gas jets coupled to a system of 3 gyros, 4 primary Sun sensors, 2 secondary Sun sensors, and an Earth sensor. Power was supplied by 9792 Si solar cells contained in the two solar panels, giving a total array area of 2.3 square meters and producing 200 W. Two 1200 Watt-hr AgZnO batteries rated at 26.5 V with a capacity for 9 hours of operation provided power to each of the separate communication/TV camera chains. Two 1000 Watt-hr AgZnO batteries stored power for spacecraft operations.

   Communications were through the quasiomnidirectional low-gain antenna and the parabolic high-gain antenna. Transmitters aboard the spacecraft included a 60 W TV channel F at 959.52 MHz, a 60 W TV channel P at 960.05 MHz, and a 3 W transponder channel 8 at 960.58 MHz. The telecommunications equipment converted the composite video signal from the camera transmitters into an RF signal for subsequent transmission through the spacecraft high-gain antenna. Sufficient video bandwidth was provided to allow for rapid framing sequences of both narrow- and wide-angle television pictures.

Mission Profile

   Ranger 6 was launched into an Earth parking orbit and injected on a lunar trajectory by a second Agena burn. The midcourse trajectory correction was accomplished early in the flight by ground control. On February 2, 1964, at 9:24:32 UT, 65.5 hours after launch, Ranger 6 impacted the Moon as planned on the eastern edge of Mare Tranquillitatis (Sea of Tranquility) at 9.3864 N, 21.4806 E (impact site identified from Lunar Reconnaissance Orbiter images). The trajectory of the spacecraft was on target and the orientation of the spacecraft to the surface during descent was correct, but no video signal was received and no camera data obtained. A review board determined the most likely cause of failure was due to an arc-over in the TV power system when it inadvertently turned on for 67 seconds approximately 2 minutes after launch during the period of booster-engine separation. 

Ranger VI lifts off from Launch Complex 12 aboard an Atlas Agena launch vehicle.

© 2026, Andrew Mirecki

30 January 1996

Comet Hyakutake (C/1996 B2) on March 26, 1996. Credit: Doug Zubenel

On January 30, 1996 (January 31 in Japan), comet Hyakutake (C/1996 B2) was discovered by Japanese amateur astronomer Yuji Hyakutake (1950–2002), who tracked it down using a pair of 25 x 150 binoculars.. The comet passed Earth at a distance of 15 million km (0,10 au) on March 25, 1996. It was one of the closest cometary approaches of the previous 200 years. Reaching an apparent visual magnitude of zero and spanning nearly 80°, Hyakutake appeared very bright in the night sky and was widely seen around the world. The comet's head appeared distinctly blue-green, possibly due to emissions from diatomic carbon (C2) combined with sunlight reflected from dust grains.

   Hyakutake is a long-period comet that passed perihelion at 0.23 au on May 1, 1996. Before its most recent passage through the Solar System, its orbital period was about 17,000 years, but the gravitational perturbation of the giant planets has increased this period to 70,000 years. This is the first comet to have an X-ray emission detected, which is most likely the result of ionised solar wind particles interacting with neutral atoms in the coma of the comet. The Ulysses spacecraft fortuitously crossed the comet's tail at a distance of more than 500 million km from the nucleus, showing that Hyakutake had the longest tail known for a comet.

The last known observation of the comet took place on November 2, 1996.

The near-nucleus region of Comet Hyakutake imaged by the Hubble Space Telescope on March 27, 1996. Some fragments can be seen breaking off. Credit: H. Weaver (ARC), HST Comet Hyakutake Observing Team, and NASA

© 2026, Andrew Mirecki