Chinese rover finds lunar nights ‘colder than expected’

Posted: February 2, 2019 by oldbrew in exploration, moon, Temperature

View from the Moon [credit: NASA]

Quoting from another report: ‘Data from the Apollo missions had already revealed that the moon’s sunlit surface can climb to 260 degrees Fahrenheit (127 degrees Celsius) during the day, and drop to minus 280 F (minus 173 C) at night. But all of that data comes from the side of the moon that faces Earth.’ They think the answer to the mystery lies in the soil, which might raise other questions about the rotating sphere with no ‘sides’ that the lander is on.

China’s lunar lander has woken from a freezing fortnight-long hibernation to find night-time temperatures on the moon’s dark side are colder than previously thought, the national space agency said Thursday.

The Chang’e-4 probe—named after a Chinese moon goddess—made the first ever soft landing on the far side of the moon on January 3, a major step in China’s ambitions to become a space superpower, says

Temperatures on the moon’s surface plummeted to minus 190 degrees celsius (-310 degrees Fahrenheit) during the probe’s first lunar night, which “was colder than scientists expected,” the China National Space Administration (CNSA) said.

The night-time temperatures were recorded by the Chinese probe after it became active on Wednesday, following a slumber that lasted for about two earth weeks.

They were lower than those recorded by previous US missions to the near side of the moon, Zhang He, executive director of the Chang’e-4 mission, told Xinhua news agency.

“That’s probably due to the difference in lunar soil composition between the two sides of the moon,” he said.

Full report here.

  1. A C Osborn says:

    Does that affect the Overall Temperature enough to also affect N & Z calculations?

  2. Graeme No.3 says:

    They should blame the polar vortex.

  3. Jim says:

    Interesting, but the composition of the moon should have been similar on both sides. Each is sunlight for similar times, supposedly equally heated, but one faces earth. An additional heating source. One would wonder, if the same apparent difference can be found on the space station. Earthside vs. hidden side?

  4. tallbloke says:

    That’s 83K. Pretty chilly, you’ll need a hat and scarf.
    The rover is in the Aitken basin, which is near the lunar south pole:

    The DIVINER model got 93K as equatorial Tmin. As reported in N&Z’s first paper:

  5. Richard111 says:

    I doubt the Earth is an additional heating source, but I suspect it can reduce the rate of cooling for surfaces directly facing the Earth.

  6. HM says:

    re: the composition of the moon regolith

    not sure of the source but someone suggested the Earth’s magnetic field forms a plasma sheath slightly deflected towards the moon. That after meteorites disintegrate in the Earth atmosphere (which happens all the time), some ionized very fine particles are carried to the closer lunar surface.

    This would make the near side of the moon have a thicker regolith – seemingly paradoxical / despite being less exposed.

  7. Ed Bo says:

    The properties of the surface on the far side of the moon are substantially different (on average of course) from the near side. This was a big surprise the first time we were able to survey the far side.

  8. oldbrew says:

    Ed Bo says: February 3, 2019 at 2:17 am

    Which raises the question of whether constantly facing the Earth has had a long-term effect on its near-side surface – and if so, how that might work.

  9. Jim says:

    But, we are getting second hand reports. An asside, never used a rock to reflect heat of a campfire toward the door of a tent? It works. Since the earth is modeled as a black body, it does reflect some of the radiation inputted. Some is reflected toward the moon. Not a lot but some. Backscatter. But. So a tidally locked body should be warmer on the earthside? Illogically, the sunside is colder? I don’t rember reading of large enough of a magnetic field to collect stuff, but, there should be more exposed sunside elements on the dark side then the earthside because of Earth’s magnetic fields. Interesting. Should they be mapping ion distributions?

  10. elcrustace says:

    Temperature without atmosphere? Colder than expected? It’s just thermal radiation. Easily measured with satellites.

  11. gymnosperm says:

    We used to think only H and He could escape the earth’s gravitation, but recently even O ions seem to be stripped from our atmosphere by solar ejections and blown, periodically, towards the moon.

    The moon’s regolith (cheese) is itself thought to have been stripped from the earth by impact. How this cheese would differ in emissivity on the far side, even given periodic accretions of earth stuff on the near side, would require considerable explanation.

    I’m with Jim and his campfire reflecting rock. Thermometers on the near side register both the moon’s emissivity and earthlight.