Tuesday, January 2, 2024

New Satellites, Old Satellite; New Mission, Old Mission

The first launch of calendar '24 is scheduled for Tuesday night from Vandenberg SFB in a three hour launch window that begins at 7:22PM PST - aka 10:22PM EST.  The launch, called Starlink group 7-9, includes the first batch of Starlink satellites with direct-to-cell phone capability.  

"This launch will include the first six Starlink satellites with Direct to Cell capabilities that will enable mobile network operators around the world to provide seamless global access to texting, calling, and browsing wherever you may be on land, lakes, or coastal waters," SpaceX wrote in a mission description.

The direct to cell phone or smart phone coverage was first agreed to between T-Mobile and SpaceX in August of 2022 in plan called "Coverage Above and Beyond" that Musk referred to as "a massive game changer" for the users.  

"I think this is really a massive game changer," Musk said. "In a nutshell, it's no more dead zones."

The current landscape features plenty of dead zones — remote regions far from cell towers where smartphone users can't get a signal. Indeed, there are about 500,000 square miles (1.3 million square kilometers) in the United States that aren't covered by any cellular network, [T-Mobile president and CEO Mike] Sievert said.

Perhaps most unusual of all, this mission will fly on the first mission of a new, unused, Falcon 9 booster.  The booster will be as new as the satellites its lifting.

From the "things were really happening over the last two weeks" category, we learn that NASA's Juno probe that's orbiting Jupiter made the closest pass of its mission over Io, Jupiter's most volcanically active moon.

The spacecraft came to within 930 miles (1,500 km) of the surface of Io, a dense moon that is the fourth largest in the Solar System. Unlike a lot of moons around Jupiter and Saturn, which have surface ice or subsurface water, Io is a very dry world. It is also extremely geologically active. Io has more than 400 active volcanoes and is therefore an object of great interest to astronomers and planetary scientists.

Images from the December 30 flyby were posted by NASA over the New Year holiday weekend, and they provide some of the clearest views yet of this hell-hole world. The new data will help planetary scientists determine how often these volcanoes erupt and how this activity is connected to Jupiter's magnetosphere—Io is bathed in intense radiation from the gas-giant planet.

Juno arrived at the Jovian system in July 2016 and in its 56 flybys of Jupiter has never gotten this close to Io, coming only within "several thousand miles" of the moon.  Juno is programmed to make another close flyby of Io on Saturday February 3rd which will allow scientists to compare changes on the moon's surface over a short period of time. 

Surviving over seven years in the hostile environment around Juno is no small feat, and because of the radiation in the system all the electronics on the spacecraft need to be radiation hardened.  That doesn't eliminate damages, it pretty much simply slows the damage.   

"The cumulative effect of all that radiation has begun to show on JunoCam over the last few orbits," said Ed Hirst, project manager of Juno at NASA’s Jet Propulsion Laboratory in Southern California. "Pictures from the last flyby show a reduction in the imager’s dynamic range and the appearance of ‘striping’ noise. Our engineering team has been working on solutions to alleviate the radiation damage and to keep the imager going."

Juno image of Io from the December 30th flyby.  NASA/SWRI image

Eventually, the radiation wins and Juno will have to be abandoned.  Currently, the plan is for the mission to operate until September 2025.  At that point, the satellite will be steered into Jupiter's atmosphere so that it will burn up and be destroyed.


  1. I saw the Vandenberg Falcon launch from my yard, about 90 miles away, quite spectacular for one of these.

    1. Jealous of you. But then again, used to watch the Minuteman launches from the back yard on Cherry Street at Vandenberg AFB in the late 60's.

      Miss Vandenberg.

      Miss the Cape, too.

    2. You know, as a child we lived in Santa Maria and I’m told that we watched launches but I don’t actually recall.

      I would like to get out closer to watch one of these days.

      the weather was a bit iffy lately, but it cleared for the launch, and the ground track seemed to have brought it closer to my house than usual.

      I wonder if there is a way to get the launch ground track?


    3. There's a guy on X (or Twitter or whatever we're supposed to call it) who does that regularly. https://twitter.com/Raul74Cz

      I never subscribed to Twitter, so I can't see if he posted a track for that launch, but here's an older example.

      When the weather pushed the time out past 11:30 PM local, I called it a night and went to bed, since I had to get up early. Early for me, a retired old dude.

    4. Thanks for the links, looks promising.I haven’t joined twitter (or any social media) but now I am tempted.

    5. I was one of the guys doing the launching back in '76.
      Good times!

    6. The hills between Santa Maria and Vandenberg block the launch view, though you can see the rockets once they're up 'there'.

      When living at Satellite Beach, if we knew a launch was happening we could either go down to the beach or climb up on the house to watch launches from the Cape.