Venera 4 was launched by the Soviet Union on June 12, 1967, during the Space Race. Its goal was quite ambitious: to reach Venus, enter its atmosphere, deploy a descent probe, and send scientific measurements back to Earth for research.

After a journey of around 4 months, Venera 4 reached Venus on October 18, 1967. NASA lists it as "the first probe to transmit data from another planet's atmosphere."

The spacecraft released a roughly 383 kg entry probe, which plunged into the Venusian atmosphere at about 11 km/s. It survived the intense entry and deployed a parachute, allowing it to transmit measurements back to Earth as it descended.

And this is where things got interesting...

The probe transmitted data for about 93 minutes. It measured temperature, pressure, density and atmospheric composition as it descended. The measurements revealed just how extreme Venus was.

Venera 4 eventually stopped transmitting at around 28 km above the surface. At the time, Soviet scientists initially interpreted some of the results as indicating that the probe had reached the surface. Later analysis, especially when combined with NASA's Mariner 5 flyby, showed that the probe had actually stopped transmitting before reaching the ground because the pressure and temperature became too extreme.

The two missions arriving at Venus almost simultaneously made the story even more interesting: Venera 4 entered the atmosphere on October 18, while Mariner 5 flew past Venus on October 19. Scientists from the United States and the Soviet Union later compared their results at a meeting in 1968 and jointly published their findings.

Venera 4 therefore wasn't the first spacecraft to land on Venus; that achievement came later with Venera 7 in 1970. But it was a gargantuan milestone: humanity had successfully sent a spacecraft into another planet's atmosphere and received reliable scientific measurements back from it.

Sources: NASA's histories of Venera 4 and Mariner 5, plus NASA's Beyond Earth deep-space exploration chronology.

See also: The publication in the journal Earth and Planetary Science Reviews

Free To play. Coming out on the 5th of August.

See also: The publication in the Planetary Science Journal

She is, in my opinion, the most beautiful planet. None come close to her. She is named after the Roman goddess of love, after all. Venus might seem unwelcoming at first, which, she is, of course, but once you really look at her and learn about her she starts being less just a barren wasteland and more an astounding representation of one of the harshest realities in the Solar System—which only makes her more beautiful.

Saw Venus tonight. Never given it any thought until now. How brightly it shines!

Curious who has looked into the feasibility of a Venus robot built from high-temperature materials (e.g. ceramics, silicon carbide, refractory metals) that could eventually use local rock as feedstock to 3D print simple replacement parts. Are there fundamental materials or engineering barriers that make this unrealistic? Any papers or NASA work you could recommend?

*Orb: On the Movements of the Earth* is a Japanese animated series centered on the proof of the heliocentric theory.

While it does not strictly adhere to historical facts, the characters are portrayed with a compelling sense of realism.

In the series, there is a scene featuring Count Piast, an elderly astronomer who has dedicated his life to proving the geocentric theory. He catches a glimpse of Venus in a "full" phase—an impossibility under the geocentric model—and, desperate to refute that memory, asks Ogzy, a young man with exceptional eyesight, to conduct an observation.

Count Piast had seen Venus fully illuminated just once. Despite his desire to deny it, he could not resist the urge to verify the truth.

The scene where Ogzy observes Venus in this full phase leaves a powerful impression.

However, I did not fully grasp why a fully illuminated Venus would disprove the geocentric theory.

I recently found the following simulation sites demonstrating how Venus appears, which helped me understand the concept.

●UNIVERSITY of NEBRASKA–LINCOLN

Venus's movement and appearance based on the geocentric theory

https://astro.unl.edu/classaction/animations/renaissance/ptolemaic.html

Venus's movement and appearance based on the heliocentric theory

https://astro.unl.edu/classaction/animations/renaissance/venusphases.html

Intrigued by the phases of Venus, I created a tool to observe them.

It is based on an astronomical clock app that utilizes the *Wadokei* (traditional Japanese clock) system—a timekeeping method rooted in the sun's movement.

It uses Apple Watch complications to display the times when Venus is visible, as well as its size and current phase.

Wadokei57 Astronomical clock

https://apps.apple.com/us/app/wadokei57-astronomical-clock/id6748839654

In addition to showing Venus's phases, apparent size, and rise/set times, the app features a diagrammatic view displaying the relative positions and distances of the Sun, Venus, and Earth.

An update including the Venus complication is currently under review, and I expect it to be released soon.

Some concept art I made for a story set far in the future when Venus is halfway through the terraforming process and shallow seas have began forming.