Now it’s really happening! NASA launches the first rocket of the Artemis program, which in a few years will return astronauts to the surface of the moon, after a 50-year hiatus. The unmanned Orion capsule will arrive at the moon in a few days, and the mission will last 42 days. Artemis is a program that could eventually be worth nearly $100 billion, and the first big step will be taken in the next few hours.

SLS, delays and problems

In May 2019, the then head of NASA announced that the mission to return humans to the moon would be named after Artemis, a goddess who, according to mythology, was the twin sister of the Greek god Apollo. It has special significance: the Apollo program first landed men on the moon more than 50 years ago. Artemis will return humans to the moon, the idea is that this time humans will finish building a lunar base after 2030.

It’s a long way to get there. In 2012, it was estimated that the SLS rocket could be built for six billion dollars, but so far more than 23 billion have already been spent, and the rocket has already launched for the first time. A decade ago, it was believed that the launch could cost 500 million dollars, but the latest estimates indicate more than 4 billion for the launch. Ten years ago, the most optimistic believed that the rocket could be launched in 2017.

It’s an expensive program, the audit estimates, costing $93 billion between 2012 and 2025, when four Americans are expected to set foot on the moon’s south pole as part of the Artemis III mission. Already in May 2024, the Orion capsule should send several astronauts on a mission around the moon, but without landing. The schedule is likely to change as there are many technical issues and many questions are postponed.

NASA reuses important elements

Artemis is an expensive program that’s been delayed, but it’s great that it exists, that it’s funded, and will send humans to the moon for the first time since 1972. NASA is a changed institution, even if it still works in small steps. and very carefully.. NASA is working more efficiently than ten years ago, and it is clear that it is very important to work with private companies like SpaceX and Blue Origin, and not only with large aeronautical concerns. However, various elements were built on the SLS by major companies: Boeing, Aerojet Rocketdyne, Northrop Grumman and United Launch Alliance (a joint venture between Lockheed Martin and Boeing).

Then it should be said that the engines on the SLS rocket, which launches on Monday, are part of the NASA inventory and have been used by the space shuttles in the past. These are the engines that have been used on past space shuttle flights (over 20 flights in total), but unfortunately, the Artemis mission will not have the engines recovered, but will fall into the Pacific Ocean after the first stage fuel is exhausted. was used completed

The SLS rocket has four RS-25 engines and two auxiliary boosters. The main stage tanks will contain a total of 3.3 million liters of liquid hydrogen and liquid oxygen.

The Orion capsule is also not new: it was built almost 20 years ago, but the cancellation of the Constellation program in 2010 meant that Orion could not go into space. After a series of modifications, Orion will reach space and become essential to the Artemis program, provided it can be successfully recovered and thus safely reach ocean waters.

In the capsule will not be people, but three mannequins: Helga, Zohar and Commander Munikin Campos, two mannequins equipped with plastic models of human organs, the purpose of which is to measure the effects of cosmic radiation on future astronauts.

Orion should lift off when the SLS rocket reaches 3,700 km from Earth, and the engines will carry it on a mission around the moon, after which Orion will travel 2 million km in 42 days and reach 100 km of the lunar surface. The return is scheduled for October 10, in the waters of the Pacific Ocean.

Orion and what happens immediately after launch

On September 3, Orion will reach the closest point to the surface of the Moon (altitude 100 km), and on September 8, it will reach the farthest point reached by a space shuttle designed to carry people (more than 450,000 km from Earth, surpassing the record set by Apollo 13 in April 1970 The Moon is 384,000 km from Earth, and Orion will reach its maximum point 64,000 km from the Moon.

Orion will also launch 10 small satellites, called “cubsats,” to study the moon and its surroundings.

Orion cannot land, but it will also be used in the Artemis III mission, which will return humans to the lunar surface in 2025 or later. Orion will take astronauts into lunar orbit, near the south pole, and they will arrive on the surface of the moon after landing in a capsule that will be built by SpaceX.

A big advantage is that Orion is designed to also handle re-entry into the Earth’s atmosphere from interplanetary orbit (where speeds are higher than re-entry from lunar orbit), meaning NASA will be able to use the capsule for future missions to Mars and from it.

On August 29, two minutes and 12 seconds after launch, the boosters disengaged and fell into the ocean. Eight minutes after launch, the rocket’s orange main stage will detach. After that, Orion will be in Earth orbit with the rocket’s upper stage still attached to it.

Orion’s solar arrays will open, followed by an Earth orbit, and the upper stage will set Orion on the correct trajectory toward the Moon and detach from the capsule two hours after launch. About half an hour before that time, Orion will reach a speed of more than 35,000 km/h.

The journey back to Earth will begin on October 3, but the point of maximum distance from Earth will be reached on September 24. When re-entering the atmosphere, Orion will reach a maximum speed of more than 39,000 km at an altitude of more than 130 km. It will also be possible to see if the heat shield perfectly withstands temperatures of several thousand degrees, after re-entry into the atmosphere, and then three special parachutes will have to open.