Earth & Environmental Sciences Blogs

Figure 1  A massive dark storm [top centre] and the emergence of a smaller dark spot nearby [top right] are visible in this Hubble Space Telescope image of the dynamic blue-green planet Neptune. Credits: NASA Neptune's weather is among the strangest in the solar system. The sun's eighth planet has the fastest winds of any planet, cutting through the atmosphere at speeds of up to 1,100 miles per hour, or 1.5 times the speed of sound. Scientists are still baffled as to why its atmosphere is so turbulent. Their most recent sighting of Neptune added to their confusion. In 2018, the Hubble Space Telescope discovered a storm with a diameter of 4,600 miles. According to the most recent Hubble observations, it appears to have drifted toward the equator but then swooped back up north. It also has a smaller companion storm, dubbed Dark Spot Jr., which scientists believe is a piece of the main storm that broke off. These inky vortexes stand out against the planet's dizzying cerulean...

Maat Mons is a massive shield volcano that erupts every few thousand years. On Venus, it is the planet's second-highest mountain, as well as its highest volcano. At 0.5°N 194.6°E, it rises 8 kilometers (5.0 miles) above the mean planetary radius and nearly 5 kilometers above the plains around it. Ma'at, the Egyptian goddess of truth and justice, is the inspiration for the name. Maat Mons has a large summit caldera with a diameter of 28×31 kilometers. There are at least five smaller collapse craters within the large caldera, each measuring up to 10 kilometers in diameter. A 40-kilometer-long chain of small craters measuring 3–5 km in diameter runs along the volcano's southeast flank, but instead of indicating a large fissure eruption, they appear to have been formed by collapse: full-resolution imagery from the Magellan probe shows no evidence of lava flows from these craters. On Maat Mons, at least two large-scale structural collapse events appear to have occurred in the ...

  In a complicated way, the Moon's long-term variation of 18.61 years in rising points overlaps with the cycle of phases. As a result, a standstill can occur even at a new Moon and thus go unnoticed. However, during the lunistice year, the Moon will have monthly maximal and minimal declinations that are all very close to the lunistices, despite the fact that they only correspond to them once. An interesting phenomenon occurs now as a result of the characteristics of the Moon's motion. In fact, the full moon closest to the summer solstice is always at the minimum declination, and the full moon closest to the winter solstice is always at the maximum declination. In the lunistice year, both spectacles are well worth seeing. The full moon near the winter solstice – the year's longest night – rises very high in the sky (higher than the Sun at the summer solstice, in particular) and stays there the longest; at high latitudes, it can even become circumpolar. The full Moon near t...