On this day in 1977 was launched the space probe Voyager 1.
Voyager 1 is a space probe launched by NASA on September 5, 1977. Part of the Voyager program to study the outer Solar System, Voyager 1 launched 16 days after its twin, Voyager 2. Having operated for 41 years as of September 5, 2018, the spacecraft still communicates with the Deep Space Network to receive routine commands and return data. At a distance of 142.31 astronomical units from the Sun as of June 4, 2018, it is the most distant man-made object from Earth.
The probe’s objectives included flybys of Jupiter, Saturn, and Saturn’s largest moon, Titan. While the spacecraft’s course could have been altered to include a Pluto encounter by forgoing the Titan flyby, exploration of the moon, which was known to have a substantial atmosphere, took priority. It studied the weather, magnetic fields and rings of the two planets and was the first probe to provide detailed images of their moons. (read more)
A ground-penetrating radar aboard the European Space Agency’s Mars Express satellite has found evidence for a pool of liquid water, a potentially habitable environment, buried under layers of ice and dust at the red planet’s south pole.
“This subsurface anomaly on Mars has radar properties matching water or water-rich sediments,” said Roberto Orosei, principal investigator of the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument, or MARSIS, lead author of a paper in the journal Science describing the discovery.
The conclusion is based on observations of a relatively small area of Mars, but “it is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered,” added Orosei.
Scientists have long theorised the presence of subsurface pools under the martian poles where the melting point of water could be decreased due to the weight of overlying layers of ice. The presence of salts in the Martian soil also would act to reduce the melting point and, perhaps, keep water liquid even at sub-freezing temperatures.
Earlier observations by MARSIS were inconclusive, but researchers developed new techniques to improve resolution and accuracy.
“We’d seen hints of interesting subsurface features for years but we couldn’t reproduce the result from orbit to orbit, because the sampling rates and resolution of our data was previously too low,” said Andrea Cicchetti, MARSIS operations manager.
“We had to come up with a new operating mode to bypass some onboard processing and trigger a higher sampling rate and thus improve the resolution of the footprint of our dataset. Now we see things that simply were not possible before.”
MARSIS works by firing penetrating radar beams at the surface of Mars and then measuring the strength of the signals as they are reflected back to the spacecraft.
The data indicating water came from a 200-kilometre-wide (124-mile-wide) area that shows the south polar region features multiple layers of ice and dust down to a depth of about 1.5 kilometres (0.9 miles). A particularly bright reflection below the layered deposits can be seen in a zone measuring about 20 kilometres (12 miles) across.
Orosei’s team interprets the bright reflection as the interface between overlying ice and a pool or pond of liquid water. The pool must be at least several centimetres thick for the MARSIS instrument to detect it.
“The long duration of Mars Express, and the exhausting effort made by the radar team to overcome many analytical challenges, enabled this much-awaited result, demonstrating that the mission and its payload still have a great science potential,” says Dmitri Titov, ESA’s Mars Express project scientist.
The discovery is significant because it raises the possibility, at least, of potentially habitable sub-surface environments.
“Some forms of microbial life are known to thrive in Earth’s subglacial environments, but could underground pockets of salty, sediment-rich liquid water on Mars also provide a suitable habitat, either now or in the past?” ESA asked in a statement. “Whether life has ever existed on Mars remains an open question.”
The Venera series space probes were developed by the Soviet Union between 1961 and 1984 to gather data from Venus, Venera being the Russian name for Venus. As with some of the Soviet Union’s other planetary probes, the later versions were launched in pairs with a second vehicle being launched soon after the first of the pair.
Ten probes from the Venera series successfully landed on Venus and transmitted data from the surface of Venus, including the two Vega program and Venera-Halley probes. In addition, thirteen Venera probes successfully transmitted data from the atmosphere of Venus.
Among the other results, probes of the series became the first human-made devices to enter the atmosphere of another planet (Venera 4 on October 18, 1967), to make a soft landing on another planet (Venera 7 on December 15, 1970), to return images from the planetary surface (Venera 9 on June 8, 1975), and to perform high-resolution radar mapping studies of Venus (Venera 15 on June 2, 1983). The later probes in the Venera series successfully carried out their mission, providing the first direct observations of the surface of Venus. Since the surface conditions on Venus are extreme, the probes only survived on the surface for durations varying between 23 minutes (initial probes) up to.
The voyage of Apollo 17 marked the program’s concluding expedition to the moon. The mission lifted off after midnight on December 7, 1972 from Kennedy Space Center and touched down on the lunar surface on December 11. The crew spent almost 75 hours on the lunar surface, conducted nearly 22 hours of extravehicular activities (EVAs), and traveled almost 19 miles in the Lunar Roving Vehicle (LRV). During lunar lift-off on December 14, Apollo 17 Mission Commander Eugene A. Cernan remarked that the astronauts were leaving as they came, “with peace and hope for all mankind.” In this photo, taken during the second spacewalk on December 12, 1972, Cernan is standing near the lunar rover designed by Marshall Space Flight Center in Huntsville, Ala.
This gold aluminium cover was designed to protect the Voyager 1 and 2 “Sounds of Earth” gold-plated records from micrometeorite bombardment, but also serves a double purpose in providing the finder a key to playing the record. The explanatory diagram appears on both the inner and outer surfaces of the cover, as the outer diagram will be eroded in time. Flying aboard Voyagers 1 and 2 are identical “golden” records, carrying the story of Earth far into deep space. The 12 inch gold-plated copper discs contain greetings in 60 languages, samples of music from different cultures and eras, and natural and man-made sounds from Earth. They also contain electronic information that an advanced technological civilization could convert into diagrams and photographs. Currently, both Voyager probes are sailing adrift in the black sea of interplanetary space, flying towards the outmost border of our solar system.
On this day in 1972 Pioneer 10 was launched toward Jupiter.
Pioneer 10 is an American space probe, launched in 1972 and weighing 258 kilograms (569 pounds), that completed the first mission to the planet Jupiter.Thereafter, Pioneer 10 became the first of five artificial objects to achieve the escape velocity that will allow them to leave the Solar System. This space exploration project was conducted by the NASA Ames Research Center in California, and the space probe was manufactured by TRW Inc. (read more).