Today NASA released a report outlining its plans for sustainable lunar exploration and development and how it relates to the longer term goal of sending humans to Mars. The 13-page report to the White House National Space Council lacks specifics, but helps to connect the dots between the near-, mid- and long-term goals of the human spaceflight program.

NASA’s immediate focus is fulfilling the Trump Administration’s directive to put astronauts back on the Moon by 2024, the end of a second Trump term if he wins reelection this fall. Called the Artemis program, details of the exact plan, or architecture, for doing that are eagerly awaited. They were expected to be revealed at a March 24 meeting of the Space Council, but it was postponed amidst the coronavirus crisis.

NASA’s concept for getting humans on the Moon by 2024 is evolving and apparently underwent a significant change in recent weeks. This report does not clarify what the revised plan is, however.

The idea had been that astronauts in Orion spacecraft would launch to a small space station, Gateway, in lunar orbit aboard NASA’s new big rocket, the Space Launch System (SLS). There they would transfer to Human Landing Systems (HLS), previously launched in segments and assembled at the Gateway, for the trip down to and back from the surface. Orion would then bring them back to Earth. Between 2024 and 2028, the Gateway would expand to include modules and other hardware provided by international partners and continue to be a transfer point for crews and a scientific research facility. Commercial companies would provide logistics support.

However, last month Doug Loverro, the new head of human space exploration at NASA, told an advisory committee that the Gateway no longer was a mandatory part of the Moon-by- 2024 phase of the Artemis program. He insisted NASA was still committed to building it, but later as part of the sustainability phase. Apparently getting astronauts to the lunar surface by 2024 will be accomplished using SLS and Orion with some other type of landing system that is not assembled at the Gateway.

He did not go into details of what the alternative landing system is and this report does not either. It devotes a considerable amount of its 13 pages to the role of Gateway for both sustainable lunar operations and Mars exploration, but is vague about its timetable. “Orion will deliver the first crew to Gateway when the human landing system (HLS) capability can enable lunar expeditions to be staged from the stable Gateway orbit” and “will offer astronauts easier crew returns, a safe haven in the event of an emergency, the ability to navigate to different orbits around the Moon and later, an advancement in human life support systems.”

Whenever it is built, international and commercial partners are still expected to play important roles. The report notes that Canada, Japan and Europe already have indicated interest and Russia may provide an airlock. NASA just awarded the first logistics contract to SpaceX, although no date was mentioned as to when Gateway might need logistics support.

According to the report, Gateway also now is envisioned to serve in an analog mode for a Mars mission. Four astronauts would live on Gateway for many months, similar to an outbound Mars journey, then two would travel down to the lunar surface to simulate a Mars landing excursion, then return to the Gateway and their crewmates and stay for many more months as though returning from Mars.

When that mission or actual trips to Mars might take place is also unclear. NASA officials often talk about humans going to Mars in the 2030s and that time frame is mentioned once in passing, but the section on Mars exploration identifies the many difficult challenges that must be overcome first and says only that such journeys will take place “as soon as possible.”

The bulk of the report is about what happens between 2024 and eventual trips to Mars — the sustainability phase — and how lunar missions enable Mars exploration.

An Artemis Base Camp at the Moon’s South Pole, a Lunar Terrain Vehicle, habitats, solar and nuclear power systems, in-situ resource utilization (ISRU) systems, and the Gateway will “ensure that our return to the Moon is sustainable and leads directly to the first human mission to Mars.” Durations on the lunar surface will grow from seven days to one-to-two months.

Except for the 2024 date, the timetable for all of these activities is up in the air. Many factors are involved, including “capability maturity and availability, budget, launch vehicle availability, and system complexity,” but NASA is intent on creating an “annual cadence of demonstrable progress and a gradual increase in mission duration and complexity.”

Loverro and others from the Human Exploration and Operations Mission Directorate (HEOMD) are scheduled to brief the NASA Advisory Council’s Human Exploration and Operations committee on April 14-15 about the Artemis program.

Today’s report was written for Vice President Pence, who chairs the Space Council, and it may meet his needs, but there is little question that the outlook for the Artemis program is decidedly less promising than just a few weeks ago. The coronavirus crisis, with its dire economic consequences, has completely changed the landscape.

Meeting the 2024 goal, never mind all that follows, requires a lot of money. NASA is requesting $71 billion over the next five years (FY2021-2025) to execute Artemis on top of its other activities. The agency wants a 12 percent overall increase for FY2021 — $25.2 billion compared to $22.6 billion in FY2020. Whether Congress will think that a wise investment while spending trillions to keep the economy afloat is highly questionable. Not to mention that NASA’s authorization committees have not agreed on the plan NASA was putting forward a few months ago, with sharp differences between the House and Senate versions. Without a united front, it will be all that more difficult to move forward.