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Archive for the ‘Artemis Program’ Category

09/16/2021 – Ephemeris – How safe is the Space Launch System (SLS) compared to the Space Shuttle?

September 16, 2021 Comments off

This is Ephemeris for Thursday, September 16th. Today the Sun will be up for 12 hours and 27 minutes, setting at 7:51, and it will rise tomorrow at 7:24. The Moon, 3 days past first quarter, will set at 3:10 tomorrow morning.

Tonight, the planet Saturn will appear above the bright gibbous Moon. It might be a bit hard to spot.

The big NASA moon rocket, the Space Launch System or SLS, borrowed a lot of features from the Space Shuttle. Is it any safer? The answer is yes. The Space Shuttle had no abort system for a catastrophic failure, as we saw with the Challenger accident in 1986. However, even though the SLS uses the same type solid rocket boosters that failed Challenger, the Crew in the Orion capsule is on top of the rocket with an escape system to rocket them away from an exploding core stage. With the Orion capsule, the escape tower will be jettisoned at some point before reaching orbit, possibly making escape impossible in the latter stage of powered flight. Both SpaceX’s Dragon and Boeing’s Starliner have escape rockets built in for the entire flight.

Addendum

Shuttle-SLS comparisons

Shuttle-SLS comparisons. Note that this image is 10 years old. The center core stage will, like the external tank on the shuttle, remain unpainted. So far, the cargo version of the is still in the design stage. The Multipurpose Crew Vehicle is now called the Orion Spacecraft. Credit: How Stuff Works.

09/14/2021 – Ephemeris – Lack of spacesuits just one of Artemis problems of getting humans back to the Moon

September 14, 2021 Comments off

This is Ephemeris for Tuesday, September 14th. Today the Sun will be up for 12 hours and 33 minutes, setting at 7:54, and it will rise tomorrow at 7:21. The Moon, 1 day past first quarter, will set at 12:53 tomorrow morning.

The bright gibbous Moon is a feast for binoculars or a telescope. However, the speed-up plan to land crews on the Moon in 2024 proposed by the former President is not appearing to pan out. One major item is space suits, which must be more rugged and impervious to the Lunar regolith, or soil, whose grains are tiny, angular and sharp, and get into everything, and can destroy spacesuit joints. NASA has been working on them for 14 years, and by itself could cost a billion dollars. They might be ready by 2025. Besides delays to the SLS rocket, the contract with SpaceX to furnish a lunar lander is now tied up in litigation by one of the contract losers. NASA’s trying to land humans on the Moon on one half of one percent of the Federal budget, plus do everything else it does.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hr). They may be different for your location.

Addendum

Prototype lunar spacesuit

Prototype lunar spacesuit. xEMU stands for Exploration Extravehicular Activity Mobility Unit. Of course. This uncredited image is from slashgear.com in 2019, so I wouldn’t believe the date. These xEMU suits may eventually cost a billion dollars to develop and produce. Click on the image to enlarge it.

08/23/2021 – Ephemeris – Seeking shelter on the Moon

August 23, 2021 Comments off

This is Ephemeris for Monday, August 23rd. Today the Sun will be up for 13 hours and 39 minutes, setting at 8:34, and it will rise tomorrow at 6:56. The Moon, 1 day past full, will rise at 9:39 this evening.

The area of interest on the Moon for NASA’s Artemis crewed landing program and the target for Chinese lunar ambitions is the south pole, where signs of water ice have been detected in permanently shadowed craters. That is a valuable resource, if one wants to live off the land on the Moon. There’s another resource that is also valuable in finding: shelter from radiation and the Moon’s extreme temperature swings. Those are lava tubes. They are lava channels in which lava flowed, the top and sides cooled and crusted over. They emptied when the lava ran out, leaving a hollow tube. Sometimes part of the upper crust fails, leaving what is called a skylight. Several of these skylights have been found on the Moon and even Mars.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hr). They may be different for your location.

Addendum

Lunar lava tube skylight

A skylight betrays the presence of a lunar lava tube. Credit NASA/LRO.

Lava tube in Hawai'i

Here’s an earthly lava tube on the Island of Hawai’i, I visited in 2012 with my wife. It was on the site of a coffee plantation south of Kona. Credit mine.

08/16/2021 – Ephemeris – The first Artemis mission (maybe) – CAPSTONE

August 16, 2021 Comments off

This is Ephemeris for Monday, August 16th. Today the Sun will be up for 13 hours and 59 minutes, setting at 8:46, and it will rise tomorrow at 6:47. The Moon, 1 day past first quarter, will set at 1:13 tomorrow morning.

Tonight’s Moon is a great one to view with a small telescope. Speaking of the Moon, a company called Rocket Lab will be launching the first Artemis program mission, later this year, in preparation to land crews back on the Moon. They are launching a small CubeSat to orbit the Moon in a Near Rectilinear Halo Orbit which always faces the Earth and never goes behind the Moon. To test whether all the mathematical calculations for the orbit actually work in real life. The satellite is called CAPSTONE (another tortured NASA acronym*). It will be launched from New Zealand, Rocket Lab’s main launch site first into a polar orbit before heading to the lunar orbit, taking several months to get there.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hr). They may be different for your location.

* Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment. Told ya. Cislunar space is a spherical volume of space centered on the Earth, whose radius is the Moon’s distance. Beyond that is interplanetary space.

Addendum

Rocket Lab had been planning to launch the CAPSTONE satellite from Wallops Island, Virginia, but approval was taking too long, so they moved the launch to their New Zealand launch site instead.

NASA CAPSTONE pathfinder for gateway orbit

NASA CAPSTONE* pathfinder for gateway orbit is to be launched late this year by Rocket Lab to prove out the near rectilinear orbit for the Lunar Gateway.

06/17/2021 – Ephemeris – Congress approves more money for NASA’s lunar lander

June 17, 2021 Comments off

This is Bob Moler with Ephemeris for Thursday, June 17th. Today the Sun will be up for 15 hours and 34 minutes, setting at 9:31, and it will rise tomorrow at 5:56. The Moon, at first quarter tonight, will set at 2:18 tomorrow morning. | Tonight’s Moon will be almost exactly cut in half by the sunrise terminator, since the precise moment of first quarter will be at 11:54 this evening. Speaking of the Moon, Congress has approved NASA spending of 10 billion dollars over 5 years on the Human Lander System for the Artemis Moon program. This would allow more than one bidder to win the lander contract. SpaceX’s Lunar Starship was the only one to win a contract. NASA and Congress wanted two to win, but couldn’t afford more than SpaceX. Now comes the rub… Congress will have to appropriate the money out of the budget every year for this. The target date for the first landing is 2024, which I’m pretty sure is already out of reach.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT-4). They may be different for your location.

Addendum

First Quarter Moon with binoculars or low power telescope

First Quarter Moon with binoculars or low power telescope as it might appear tonight at 11 pm. Created using Stellarium.

Three Lunar Lander proposals

Three Lunar Lander proposals. Credit Dynetics, SpaceX, and Blue Origin. Credit NASA.

Also, SpaceX’s bid was the lowest by a wide margin. With the extra funds, it looks like Blue Origin will be the second successful bidder.

04/20/2021 – Ephemeris – SpaceX gets NASA contract for Human Landing System for the Artemis (Moon) Program

April 20, 2021 Comments off

This is Bob Moler with Ephemeris for Tuesday, April 20th. Today the Sun will be up for 13 hours and 44 minutes, setting at 8:34, and it will rise tomorrow at 6:47. The Moon, at first quarter today, will set at 4:24 tomorrow morning.

Late last week NASA announced that it had selected SpaceX to provide the Human Lander System for the Artemis program. That lander is the lunar variant of the Starship SpaceX is currently testing near Boca Chica, Texas, just north of the mouth of the Rio Grande. A Starship consists of two stages: a booster called Super Heavy and the Starship upper stage. The Super Heavy returns to the launch site, while the Starship must be refueled several times in orbit to be able to head on out to the Moon. The astronauts would be launched as planned in an Orion capsule with the Space Launch System, then transfer the astronauts to the Starship waiting in lunar orbit or from the Lunar Gateway also in lunar orbit for the trip down to the lunar surface.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

SpaceX Concept lunar Lander as of 04/16/2021
SpaceX’s updated concept of their Starship lunar lander as of 04/16/2021. Credit: SpaceX.

NASA’s Source Selection Document (the rationale for their selection): https://www.nasa.gov/sites/default/files/atoms/files/option-a-source-selection-statement-final.pdf

03/25/2021 – Ephemeris – NASA successfully tests the core stage of the Artemis Moon Rocket

March 25, 2021 Comments off

This is Ephemeris for Thursday, March 25th. Today the Sun will be up for 12 hours and 25 minutes, setting at 8:02, and it will rise tomorrow at 7:34. The Moon, 3 days before full, will set at 6:57 tomorrow morning.

Last week’s 8-minute static fire test of the four Shuttle main engines of the core stage of the NASA’s Space Launch System or SLS rocket was an apparent success at the Stennis Space Center in southern Mississippi. This came after a failed test two months ago. The core stage will be refurbished and floated through the Gulf, around the tip of Florida to Cape Canaveral where the solid boosters are waiting to be mated to it in the Vertical Assembly Building. It will be used for the Artemis 1 mission to be launched late this year. That mission will take an uncrewed  Orion Crew Capsule and European Service Module to the Moon for several orbits close and more distant from it before returning to the Earth. The entire mission could take nearly a month.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Views of the SLS Core Stage green run test

Views of the SLS Core Stage green run test. Credit NASA via scitechdaily.com.

02/22/2021 – Ephemeris – What’s happening with NASA’s Artemis Moon Program

February 22, 2021 Comments off

This is Ephemeris for Monday, February 22nd. Today the Sun will be up for 10 hours and 49 minutes, setting at 6:21, and it will rise tomorrow at 7:30. The Moon, 3 days past first quarter, will set at 5:28 tomorrow morning.

It appears that the Artemis Moon Program is still on schedule despite a new administration and a setback when a few weeks ago an all up 8 minute firing of the 4 main engines of the Space Launch System Core Stage aborted after little over a minute. (NASA is scheduled to repeat this Green Run test this week) The first launch of the complete rocket is slated for later this year with an uncrewed lunar orbit mission. Recently NASA announced that Elon Musk’s SpaceX was awarded the contract to launch the first two lunar gateway modules on a single Falcon Heavy rocket. The two modules, Power and Propulsion Element (PPE) and Habitation and Logistics Outpost (HALO) will be placed in low earth orbit. From there the PPE would use its ion engines to propel the two modules out to a near rectilinear halo orbit of the Moon over many months.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

SLS first green run at Stennis

SLS first green run of all 4 RS-25 engines mounted on the core stage for the Artemis-1 mission on a test stand at Stennis Space Center in Mississippi. Credit: NASA.

Lunar Gateway PPE and HALO modules

An artist’s depiction of the Lunar Gateway PPE and HALO modules in lunar orbit. The PPE module is the part with the solar panels. Credit: NASA.