It’s Raining Mushballs on Jupiter

Here’s NASA’s explanation of this video: This animation takes the viewer high into a large storm high in Jupiter’s atmosphere, where a mushy water-ammonia particle (represented in green) descends through the atmosphere, collecting water ice in the process. The process creates a “mushball” – a special hailstone with a center made partially of liquid water-ammonia mush and a solid water-ice crust exterior. Within about 10 to 60 minutes (depending on their sizes), these mushballs reach Jupiter’s deeper layers, below the water clouds, where they rapidly melt and evaporate. Theoretical models predict these mushballs could grow to about 4 inches (10 centimeters) in diameter, weigh up to 2 pounds (1 kilogram), and reach speeds up to 450 mph (700 kph) during their descent.

Video Credit: NASA / JPL—Caltech / SwRI / MSSS / CNRS

Yeah, It’s 2020

This year has been … um … interesting, and it looks as if the summer and early autumn may bring us more intriguing events.

I’m an amateur radio operator. Many of us provide backup communications support for government agencies and NGOs (like the Red Cross and Salvation Army) during natural disasters. One of the agencies we support is the National Hurricane Center through the Hurricane Watch Net. I received an email yesterday that contained the following:

Long-range forecasts for the 2020 Atlantic Basin hurricane season, which begins on June 1 and extends until November 30, anticipate above-normal activity. The National Hurricane Center (NHC) 2020 outlook calls for a season about 140% more active than average, with four Category 3 to Category 5 hurricanes. The 2019 season saw three major hurricanes (out of six).

“The above-average prediction is largely due to the hot Atlantic and Caribbean waters and lack of a substantial El Niño in the Pacific,” the NHC explained, noting that the combination of a busy hurricane season and the ongoing COVID-19 pandemic could create a nightmare scenario for affected areas. FEMA and local emergency management agencies are already issuing COVID-19 guidelines for hurricane shelters, which include face masks and social distancing.

Given the way 2020 has gone so far, …

Morning Clouds on Mars

morning_clouds_vikingThe last missions that NASA had with orbits around Mars that were synched to view the morning weather on the planet was the Viking orbiters back in 1976. This picture was taken in August, 1976, and shows water-ice clouds in the Valles Marineris area of equatorial Mars during local morning time. North is to the upper left, and the scene is about 1,000 km across.

Although a few observations of Mars in morning daylight have come from the Viking orbiters and the European Space Agency’s Mars Express orbiter, no mission has systematically studied how morning features such as clouds, fogs, and surface frost develop during different Martian seasons on different parts of the planet. NASA’s Mars Odyssey orbiter is in the process of changing its orbit to begin systematic morning daylight observations.

Image Credit: NASA

Thunder and Lightning on Saturn

head_to_tailThis collection of images from the Cassini spacecraft orbiting Saturn shows the evolution of a massive thunder storm that circled all the way around the planet and fizzled out when it ran into its own tail. The storm was first detected on 5 December, 2010. It developed a head of bright clouds which began rapidly moving west and also spawned a much slower moving clockwise-spinning vortex.

The bright clouds at the head of the storm are indicated with red triangles. Yellow triangles mark the vortex.

The top image was taken not long after the start of the storm on 22 January, 2011. It shows the bright head of the storm just ahead of the vortex by about 40,000 km. The next image from 5 May shows that the head of the storm had traveled around the planet and started approaching the vortex from the east. The storm’s body had stretched over 220,000 km, and the head was within about 80,000 km of the vortex. That image also shows that the  vortex was losing steam compared to the head of the storm. The third image was taken on 14 June. The head of the storm had made its way roughly 290,000 km—almost entirely around the planet, and it was about to catch up with the vortex. The head of the storm was just 14,000 km east of the vortex. The bottom image, from 12 July, 2011, shows that the storm fizzled once the head and vortex met. Only the vortex remains; the bright cloud has disappeared. By late August, the storm stopped generating lightning for good.

These are false color images with the colors denoting the altitudes of the clouds. Red data is from a wavelength of radiation that penetrates the atmosphere deep down to the top of the tropospheric cloud deck (750 nm). Green represents an intermediate wavelength above the troposphere (728 nm). Blue is for a wavelength that penetrates only to the top of tropospheric haze (890 nm). White is for thick clouds at high altitudes.

Image Credit: NASA