Archive
07/22/2021 – Ephemeris – Hubble’s trouble is fixed
This is Bob Moler with Ephemeris for Thursday, July 22nd. Today the Sun will be up for 15 hours even, setting at 9:19, and it will rise tomorrow at 6:19. The Moon, 1 day before full, will set at 5:18 tomorrow morning.
Folks at NASA are breathing a sigh of relief. After a month when one of its computers failed in the Hubble Space Telescope, ground controllers were able to diagnose that the problem was actually in the computer and not somewhere else. They switched to a backup computer. This wasn’t the main computer, but the one that ran the instruments. Hubble resumed operations this past Sunday. Hubble’s more or less replacement, the James Webb Space Telescope is many years overdue to be launched, and is expected to be launched later this year by the European Space Agency from French Guiana, as their contribution to the project. The Webb telescope operates in the infrared, while Hubble operates mostly in visible light.
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
The Hubble Space Telescope after its last servicing mission. Credit: NASA.
Full scale model of the James Webb Space Telescope at Goddard Space Flight Center. Note its scale with the people in front of it.
06/17/2021 – Ephemeris – Congress approves more money for NASA’s lunar lander
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 as it might appear tonight at 11 pm. Created using Stellarium.
Three Lunar Lander proposals. Credit Dynetics, SpaceX, and Blue Origin. Credit NASA.
Technical and Management Adjectival Ratings from https://www.nasa.gov/sites/default/files/atoms/files/option-a-source-selection-statement-final.pdf
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
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
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
03/29/2021 – Ephemeris – NASA will fly spacecraft Psyche to asteroid 16 Psyche
This is Ephemeris for Monday, March 29th. Today the Sun will be up for 12 hours and 38 minutes, setting at 8:07, and it will rise tomorrow at 7:26. The Moon, 1 day past full, will rise at 9:28 this evening.
In the summer of 2022, about 15 months from now, NASA will launch a spacecraft called Psyche on a SpaceX Falcon Heavy rocket to 16 Psyche, an asteroid. 16 Psyche is a very special asteroid. It is mostly made of iron and nickel like iron meteorites and the cores of planets like the Earth. The spacecraft will be launched to get a gravity assist from Mars and will be using an ion engine to make its way to 16 Psyche and orbit it at various altitudes to see if it really is the remnant core of a protoplanet that was destroyed by collisions with other large asteroids. It would be of great interest for the future of asteroid mining companies for the precious metals it might contain. It’s big and has an average diameter of 140 miles (225 kilometers).
<p value="<amp-fit-text layout="fixed-height" min-font-size="6" max-font-size="72" height="80">The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.Addendum
03/25/2021 – Ephemeris – NASA successfully tests the core stage of the Artemis Moon Rocket
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. Credit NASA via scitechdaily.com.
03/18/2021 – Ephemeris – The aging Hubble Space Telescope survived its latest glitch
This is Bob Moler with Ephemeris for Thursday, March 18th. Today the Sun will be up for 12 hours and 4 minutes, setting at 7:53, and it will rise tomorrow at 7:47. The Moon, 3 days before first quarter, will set at 1:21 tomorrow morning.
On Sunday the 7th the Hubble Space Telescope, arguably the most famous telescope there is entered safe mode. Whenever a spacecraft finds an unexpected problem it stops what it is doing, orients itself, so its solar panels face the Sun if it can. It may or may not phone home. And waits for instructions. The last time Hubble experienced a glitch that forced a safe mode was 2018. Then it took 3 weeks to get it back to normal operations. This time it was 4 days. However, the ground controllers are still checking out one of its cameras, while the others are working again. Hubble is over 30 years old. It’s replacement, the James Webb Space Telescope is expected to finally be launched this October on the European Space Agency’s Ariane 5 rocket.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Hubble Space Telescope after a servicing mission. Credit: NASA.
Full scale model of the James Webb Space Telescope at Goddard Space Flight Center. Note its scale with the people in front of it.
I’ll be covering the James Webb Space Telescope in more detail as we count down to its launch.
02/25/2021 – Ephemeris – Moon Dust, bad stuff
This is Ephemeris for Thursday, February 25th. Today the Sun will be up for 10 hours and 58 minutes, setting at 6:25, and it will rise tomorrow at 7:24. The Moon, 2 days before full, will set at 7:30 tomorrow morning.
One of the big problems that will have to be solved before the Artemis program sets up a permanent base on the Moon is what to do about lunar soil or Moon dust. That stuff gets into everything. The Apollo astronauts said it smelled like gunpowder. Unlike beach sand the particles aren’t rounded, but angular, being produced by rocks being hit by meteoroids large and micro over the eons by space weathering. With no atmosphere small particles can even weld themselves together. Though no studies have been done, any brought into the habitat would do damage to the lungs, like that to miners on Earth. Moon dust has compromised the seals on the containers of soil the Apollo crews brought back from the Moon.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Lunar soil sample. Credit Larry Taylor U of TN Knoxville from https://ntrs.nasa.gov/api/citations/20090026015/downloads/20090026015.pdf
02/23/2021 – Ephemeris – The Perseverance rover landed on Mars taking video all the way down
Note: There was a news conference at JPL, Monday at 2 pm EST where videos of the parts of the landing were shown. Most hadn’t made it to the https://mars.nasa.gov website by Monday night. The news conference with the videos can be found on NASA TV, NASA’s YouTube channel and other sites.
This is Ephemeris for Tuesday, February 23rd. Today the Sun will be up for 10 hours and 52 minutes, setting at 6:22, and it will rise tomorrow at 7:28. The Moon, halfway from first quarter to full, will set at 6:15 tomorrow morning.
It looks like the Perseverance Rover was gently lowered to a flat spot in Jezero crater on Mars about a kilometer or two from the edge of the river delta it was aiming to be near. It is in the midst of checkouts and the unfolding of its masts and its various appendages. For the third time the Mars Reconnaissance Orbiter was able to take a picture of the entry craft on its parachute seen above the delta, as it had with Curiosity and the Phoenix lander before all the while performing its communication relay duties. A few images have come back from Percy, as the Rover is nicknamed as I record this Sunday night. By Monday Percy should have sent back more images and perhaps parts of the landing video.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
A frame from the video looking down at the Perseverance rover from the Sky Crane. In the video as the rover neared the ground it was enveloped by a cloud of dust, so the support lines simply disappeared into the cloud of dust that enveloped the rover. Click on the image to enlarge. Credit NASA/JPL.
The Perseverance rover on the parachute over Jezero crater from the Mars Reconnaissance Orbiter. The circle on the image is the point where the rover landed. Click on the image to enlarge. Credit NASA/JPL-Caltech/University of Arizona.
02/22/2021 – Ephemeris – What’s happening with NASA’s Artemis Moon Program
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 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.
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.
02/18/2021 – Ephemeris – The Perseverance Rover will land on Mars this afternoon
This is Ephemeris for Thursday, February 18th. Today the Sun will be up for 10 hours and 37 minutes, setting at 6:15, and it will rise tomorrow at 7:36. The Moon, 1 day before first quarter, will set at 1:30 tomorrow morning.
Later this afternoon the Perseverance Rover will land in Jezero crater on Mars. NASA will have a live Internet feed from the Jet Propulsion Laboratory starting at 2:15 pm EST (19:15 UTC). Atmospheric entry will be at 3:48 pm EST (20:48 UTC), landing at 3:55 pm EST (20:55 UTC). This is Earth received time. The events actually happened 11 minutes 22 seconds earlier on Mars. Though cameras on the spacecraft will be recording the landing activity it will not be sent to Earth in real time due to the weak signal during entry. The spacecraft will be sending tones only for specific events during what is called EDL, Entry, Descent and Landing or “Seven Minutes of Terror”. If all goes well the first images will be taken and sent of its surroundings. And in the next weeks we’ll get an actual replay sent back of the landing with color and sound. It will be so cool!
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Links
NASA on YouTube: https://www.youtube.com/results?search_query=nasa
NASA TV: https://www.nasa.gov/multimedia/nasatv/#public
Graphic of the Entry, Descent and Landing of the Perseverance Rover. Click on the image to enlarge. Credit: NASA/JPL.
Perseverance drilling for a sample in Jezero crater. Artist drawing – NASA/JPL
Bob Moler's Ephemeris Blog 