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Wikipedia dicit:

Ozone depletion consists of two related events observed since the late 1970s: a steady lowering of about four percent in the total amount of ozone in Earth’s atmosphere (the ozone layer), and a much larger springtime decrease in stratospheric ozone around Earth’s polar regions. The latter phenomenon is referred to as the ozone hole. There are also springtime polar tropospheric ozone depletion events in addition to these stratospheric events. In 2019, NASA announced the “ozone hole” was the smallest ever since it was first discovered in 1982.

The main cause of ozone depletion and the ozone hole is manufactured chemicals, especially manufactured halocarbon refrigerants, solvents, propellants and foam-blowing agents (chlorofluorocarbons (CFCs), HCFCs, halons), referred to as ozone-depleting substances (ODS). These compounds are transported into the stratosphere by turbulent mixing after being emitted from the surface, mixing much faster than the molecules can settle. Once in the stratosphere, they release halogen atoms through photodissociation, which catalyze the breakdown of ozone (O3) into oxygen (O2). Both types of ozone depletion were observed to increase as emissions of halocarbons increased.

Ozone depletion and the ozone hole have generated worldwide concern over increased cancer risks and other negative effects. The ozone layer prevents most harmful UV wavelengths of ultraviolet light (UV light) from passing through the Earth’s atmosphere. These wavelengths cause skin cancer, sunburn and cataracts, which were projected to increase dramatically as a result of thinning ozone, as well as harming plants and animals. These concerns led to the adoption of the Montreal Protocol in 1987, which bans the production of CFCs, halons and other ozone-depleting chemicals.

The ban came into effect in 1989. Ozone levels stabilized by the mid-1990s and began to recover in the 2000s. Recovery is projected to continue over the next century, and the ozone hole is expected to reach pre-1980 levels by around 2075. The Montreal Protocol is considered the most successful international environmental agreement to date.

Video Credit: NASA Goddard

Wikipedia dicit:

Vulcan is a next generation heavy-lift launch vehicle under development by the United Launch Alliance (ULA) to meet the demands of the United States Air Force’s National Security Space Launch (NSSL) competition and launch program.

Vulcan is ULA’s first launch vehicle design, adapting and evolving various technologies previously developed for the Atlas V and Delta IV rockets of the USAF’s EELV program. The first stage propellant tanks share the diameter of the Delta IV Common Booster Core, but will contain liquid methane and liquid oxygen propellants instead of the Delta IV’s liquid hydrogen and liquid oxygen. Vulcan’s upper stage is the Centaur V, an upgraded variant of the Common Centaur/Centaur III currently used on the Atlas V. A lengthened version of the Centaur V will be used on the Vulcan Centaur Heavy. Current plans call for the Centaur V to be eventually upgraded with Integrated Vehicle Fluids technology to become the Advanced Cryogenic Evolved Stage (ACES). Vulcan is intended to undergo the human-rating certification process to allow the launch of crew.

The Vulcan booster will have a 5.4 m (18 ft) outer diameter to support the methane fuel burned by the Blue Origin BE-4 engines. The BE-4 was selected to power Vulcan’s first stage in September 2018 after a competition with the Aerojet Rocketdyne AR1. Zero to six Graphite-Epoxy Motor-63XL (GEM-63XL) solid rocket boosters (SRB)s can be attached to the first stage in pairs, providing additional thrust during the first part of the flight and allowing the six-SRB Vulcan Centaur Heavy to launch a higher mass payload than the most capable Atlas V 551 or Delta IV Heavy. Vulcan will have a 5.4 m diameter fairing available in two lengths. The longer fairing is 21 m long, with a volume of 317 m3.

Video Credit: ULA

Wikipedia dicit:

Artemis 1 (known as Exploration Mission-1 or EM-1 before the introduction of the Artemis program) is the second planned flight of the uncrewed Orion Multi-Purpose Crew Vehicle to be launched on the first flight of the Space Launch System. The launch is planned from Launch Complex 39B at the Kennedy Space Center no earlier than November 2020. The Orion spacecraft will spend approximately 3 weeks in space, including 6 days in a retrograde orbit around the Moon. It is planned to be followed by Artemis 2 between 2022 and 2023.

The Block 1 version of the SLS rocket used on this mission will consist of two five-segment Solid Rocket Boosters, four RS-25D engines built for the Space Shuttle program and an Interim Cryogenic Propulsion Stage. Artemis 1 mission is intended to demonstrate the integrated spacecraft systems prior to a crewed flight, and in addition, test a high speed reentry (11 km/s or 6.8 mi/s) on Orion’s thermal protection system.

Video Credit: NASA

Wikipedia dicit:

The SpaceX Starship is a fully reusable second stage and space vehicle being privately developed by SpaceX. It is being designed to be a long-duration cargo- and passenger-carrying spacecraft. While currently it is tested on its own, it will be used on orbital launches with an additional booster stage, the Super Heavy, where Starship would serve as the second stage on a two-stage-to-orbit launch vehicle. The combination of spacecraft and booster is called Starship as well. Beginning in mid-2019, prototype versions are being flown with Starship as an independent rocket in its own right—without any launch vehicle booster stage at all—as part of an extensive suborbital flight testing program to get launch and landing working and iterate on a variety of design details, particularly with respect to atmospheric reentry of the vehicle.

Integrated system testing of Starship began in March 2019 with the addition of a single Raptor rocket engine to the first flight-capable propellant structure, Starhopper. Starhopper was used through August 2019 for static testing and low-altitude, low-velocity flight testing of vertical launches and landings in July/August. Two additional test articles, Starship orbital prototypes, are being built by competing teams in Texas and in Florida. They are planned to be used for high-altitude, high-velocity testing beginning in late 2019. All test articles have a 9-meter (30 ft)-diameter stainless steel hull.

Video Credit: SpaceX

Northrop Grumman dicit:

Northrop Grumman is developing the next generation of the GEM family of strap-on boosters to support intermediate- and large-class space launch vehicles. These boosters build on the company’s extensive history of the successful GEM 40, GEM 46, and GEM 60 motors. The GEM 63 and GEM 63XL motors will be capable of supporting national security, science and commercial payloads. The company is leveraging its industry-leading expertise in composite large solid rocket motor development and manufacturing to provide customers with a cost-effective, reliable, flexible, and on-time system, starting in 2019 for United Launch Alliance’s Atlas and Vulcan launch vehicles.

Video Credit: Northrop Grumman

NASA dicit:

Exploration Ground Systems continued to make sure the mobile launcher is ready for Artemis I with a multi-arm swing test on Friday, October 4, 2019 at Launch Pad 39B at Kennedy Space Center in Florida. The Umbilical Arm Simultaneous Retract Test included retraction of the connections that will provide fuel, coolant and communications to the Space Launch System rocket up until launch. The umbilicals tested included the Interim Cryogenic Propulsion Stage Umbilical (ICPSU), the Core Stage Forward Skirt Umbilical (CSFSU) and the Core Stage Intertank Umbilical (CSIU).

Video Credit: NASA