Early tomorrow morning will see the launch of an unusual European space mission called Proba-3, which will take off from Satish Dhawan Space Centre in Sriharikota, India. The launch is scheduled for around 5:30 a.m ET on Wednesday, December 4, and will see a pair of spacecraft launch into orbit to try and execute a highly precise maneuver to create an “artificial solar eclipse.”
The launch of the mission will be covered by India’s space agency, the Indian Space Research Organisation, and will also be available to stream on the European Space Agency (ESA)’s Web TV. You can watch using the link below, with coverage staring just after 5 a.m. ET (3:30 p.m. local time):
The pair of spacecraft are designed to study the sun’s corona, or the region immediately around the sun’s surface, but that comes with one big challenge: the sun is so bright that it blots out any details of the corona around it. To deal with this, one of the Proba-3 spacecraft will act as a coronagraph, meaning its job is to fly slightly in front of the other and blot out the light from the brightest part of the sun. Then the other spacecraft can take readings of the corona without the glare of the sun by using the shadow from its partner.
“ESA has flown formation flying missions before, but the distances involved have been measured in the tens of kilometers or more,” explained Damien Galano, Proba-3 mission manager. “Proba-3 is very different because our satellites will be flying just one-and-a-half football fields away from each other during active formation flying. And their relative positions will be maintained precisely to just a single millimeter for six hours at a time.”
This method of blocking out the sun means that only certain orbits will work, though. Many missions sit in low-Earth orbit, where objects like the International Space Station or the Hubble Space Telescope reside, but that wouldn’t work for Proba-3 because the strong pull of Earth’s gravity and fluctuations in the atmosphere would upset the delicate positioning of the pair. Another option would be a complex orbit around the sun called a Sun-Earth Lagrange Point, such as where the James Webb Space Telescope orbits, but this was too far away and too expensive for a small mission.
Instead, the pair will end up in an oval-shaped orbit, moving from just 370 miles altitude at its nearest to 37,000 miles at its furthest over each orbit of 19 hours and 36 minutes. The spacecraft will line themselves up autonomously when they are in a good position to observe the sun, using positioning technologies like GPS, optical cameras, a laser link, and shadow position sensors to automatically move into the correct positions.
Though the spacecraft will collect science data, the main aim of the mission is to test out this new method for observing the sun. The pair will try a variety of formations over their two-year lifespan to test out different ways to observe the sun.
After 13 suborbital test flights and more than $15 billion in development costs, SpaceX's Starship has finally reached orbit. The 407-foot megarocket, the most powerful ever built, lifted off from Starbase, Texas, on Monday and delivered its first real payload on it's 14th attempt. The celebration came with an asterisk, though, since SpaceX had to cut the planned 10-hour mission to roughly three hours.
https://twitter.com/SpaceX/status/2104601695711904180
SpaceX is finally ready to give Starship its biggest test yet. The company says the massive rocket's 14th test flight is scheduled for September 22, when it will attempt to put the upper stage into Earth orbit for the first time. The launch is currently pending regulatory approval, with a 75-minute window opening at 7:15 a.m. CT.
Starship has 26 Starlink satellites to deliver
For decades, humanity has looked up at the Moon and wondered what it would be like to live on it. Think sprawling cities, factories, research centers, and permanent human settlements. Unfortunately, there is one fairly fundamental problem with that vision.
A new study published in Frontiers in Space Technologies argues that even the Moon's potentially enormous reserves of frozen water may be nowhere near enough to support city-sized populations sustainably. Researchers Martin Elvis and Jonathan McDowell estimate that the permanently shadowed regions near the lunar poles could contain roughly one billion tons of water. It sounds like an extraordinary amount until you put a million thirsty humans next to it.