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07/11/2022 – Ephemeris – First color images from the James Webb Space Telescope will be released tomorrow
This is Ephemeris for Monday, July 11th. Today the Sun will be up for 15 hours and 20 minutes, setting at 9:28, and it will rise tomorrow at 6:08. The Moon, 2 days before full, will set at 4:19 tomorrow morning.
Tomorrow at 10:30 am, NASA and the Space Telescope Science Institute will present the first results from the James Webb Space Telescope. These will be, I believe, four multi-spectral images rendered in full color, and other data. The spectral range of Webb in the infrared is greater than Hubble Space Telescope by several factors. Hubble operates mostly in visible light and plus a bit in the ultraviolet and the near infrared. The current alignment images released are monochromatic and rendered in orange for aesthetic reasons, and to hint that these are from the long wavelength part of the spectrum. I expect the new images to look as great or better than anything the Hubble has produced. There will be a Webb image release and celebration at the Milliken Auditorium of the Dennos Museum at 10:30, with doors opening at 10 am; and also at the Main Library in Traverse City.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.
Addendum
The alignment image of the James Webb Space Telescope after the 18 primary mirror segments have been aligned to act as a single mirror. Beside the alignment star showing its overexposed diffraction spikes, many faint galaxies can be seen. The alignment star, near the Big Dipper, is almost too faint to be seen in binoculars. Credit: NASA, Space Telescope Science Institute (STScI).
Webb Fine Guidance Sensor (FGC) test image guiding on a star for 72 exposures totaling 32 hours over 8 days. The color key to brightness is white, yellow, orange, red for bright to dim. The black cores to the stars, and at least one galaxy is due to saturating the pixels due to brightness, and are not black holes. Credits: Canadian Space Agency, NASA, FGS team. The Fine Guidance Sensor is a contribution to the James Webb Space Telescope by the Canadian Space Agency.
01/18/2022 – Ephemeris – James Webb Telescope Status
This is Ephemeris for Tuesday, January 18th. Today the Sun will be up for 9 hours and 17 minutes, setting at 5:32, and it will rise tomorrow at 8:13. The Moon, 1 day past full, will rise at 6:07 this evening.
Let’s take a look at what’s happening with the Webb Space Telescope as of Sunday night when I’m recording this program, the technicians are moving the 18 mirror segments of the primary mirror away from their stowed position for liftoff to near their final position. That’s moving each of them forward about a half inch by tiny increments. Then each will be tilted to concentrate each mirror into a single image and focus it. The mirrors can be tilted and also change the curvature of the mirror segment a bit. This is what takes the time, about 5 months. All the teeny tiny adjustments take time, especially with a nearly eight and a half second two-way light-time between the Earth and the telescope.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
Mirror Alignment Tracker for January 17, 2022. It looks like most mirrors are about 3 millimeters from their final position. Shown are 19 mirrors, the center on, labeled SM is the secondary mirror, out in front of the primary mirror segments. Mirrors A3 and A6 have not moved forward very much. From their position, I assume that’s intentional. Credit: NASA.
As of yesterday (January 17, 2022) the James Webb Space Telescope has journeyed to 91% of the distance to L2 (Lagrange point 2), and its speed has dropped to 577 miles per hour (929 kilometers per hour). They do not want to overshoot the velocity to drop into a halo orbit of L2. By next week’s report, the telescope should have entered its halo orbit of L2.
01/11/2022 – Ephemeris – The James Webb Space Telescope has been unfolded but more work is needed
This is Ephemeris for Tuesday, January 11th. Today the Sun will be up for 9 hours and 5 minutes, setting at 5:23, and it will rise tomorrow at 8:17. The Moon, 2 days past first quarter, will set at 3:41 tomorrow morning.
As of Sunday night, when I’m recording this program, the James Webb Space Telescope is nearly 700 thousand miles (1,100 million kilometers) from Earth, more than two thirds the way to the L2 Lagrange point., and slowing down. It doesn’t want to overshoot the mark. The telescope is fully deployed except for the alignment of all the mirrors. 18 of which make up the 6.4 meter primary mirror. They have to be adjusted to act like a monolithic mirror with millionths of an inch tolerance. That may take 5 months. Sometime around the end of that we may get to see the First Light image from the telescope, an image of something other than the calibration stars they were using for the previous months to get all the mirrors aligned.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
James Webb Space Telescope temperatures 16 days after launch. It looks like the cold side temperatures are dropping by 1 or 2 degrees Celsius a day. Credit: James Webb Tracker by The Launch Pad YouTube Channel. Data from NASA.
12/28/2021 – Ephemeris – The James Webb Telescope is on its way to L2
This is Ephemeris for Tuesday, December 28th. Today the Sun will be up for 8 hours and 50 minutes, setting at 5:09, and it will rise tomorrow at 8:19. The Moon, 2 days past last quarter, will rise at 3:18 tomorrow morning.
The James Webb Space Telescope was launched Christmas morning and is heading out past the Moon’s orbit. It was launched from the European Space Agency’s Spaceport in Kourou, French Guiana on the northeast coast of South America, as part of their contribution to the project. It will orbit a point called Lagrange Point 2, or L2 for short, over four times the Moon’s distance in a direction opposite of the Sun. It will take the telescope 29 days to unfold itself. First order of business was to unfold the solar panels to obtain power, then to deploy its high gain antenna for communications with the Earth. Next to begin to deploy a 5 layer, tennis court sized sun shield. After that, the telescope will be unfolded.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
Addendum
The last view of Webb as it separated from the Ariane 5 launch vehicle. Credit: NASA.
12/23/2021 – Ephemeris – The James Webb Space Telescope to launch Real Soon Now
This is Ephemeris for Thursday, December 23rd. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:06, and it will rise tomorrow at 8:18. The Moon, 3 days before last quarter, will rise at 9:23 this evening.
One of the problems in recording a week’s worth of programs at once is: one, not having the freshest news; and two, talking about an imminent space launch that gets canceled a day or two before scheduled launch. As of Sunday night, when I’m recording this, the often delayed James Webb Space Telescope is scheduled to be launched at 7:20 (am EST) tomorrow morning* from the European Space Agency’s Spaceport in Kourou, French Guiana on the northeast coast of South America. It will be launched on an Ariane 5 rocket into an orbit that will take the telescope a million miles away, opposite of the direction of the Sun to a gravitational somewhat stable L2 Lagrange point, which it will lazily orbit.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.
* See? Delayed again, this time for bad weather. The launch is rescheduled for not earlier than 7:20 am EST Christmas Day. This is why I hate to talk about spacecraft launches before they happen, except in a general way.
Addendum
James Webb Space Telescope trajectory to L2 with some milestones of deployment. “ISIM” stands for Integrated Scientific Instruments Module. Credit: Space Telescope Science Institute (STScI).
Full scale model of the James Webb Space Telescope at Goddard Space Flight Center. Note its scale, with the people who worked on it the foreground.
James Webb Space Telescope, folded and ready to be placed atop the Ariane 5 Rocket. After launch and on its way to L2 begins “29 Days of Terror” as various parts of the telescope deploy, including the five layer, tennis court sized, sun shade. Any failure could doom the 10 billion dollar telescope.
10/22/2021 – Ephemeris 3,001st post – Mercury is now visible in the morning before sunrise
This is Bob Moler with Ephemeris for Friday, October 22nd. Today the Sun will be up for 10 hours and 38 minutes, setting at 6:46, and it will rise tomorrow at 8:09. The Moon, 2 days past full, will rise at 7:53 this evening.
The planet Mercury is now visible on clear mornings, low in the east-southeastern sky after 7 am, and twilight gets too bright around 7:50 am. Tiny Mercury is the smallest planet, only 50% larger than our Moon. It looks a lot like our Moon, close up, all gray and covered in craters. But the resemblance is only skin deep. Before the Arecibo radio telescope could bounce radar pulses from the planet in the 1960s, we thought Mercury held one side pointed at the Sun and the other side eternally away. That wasn’t the case due to its elliptical orbit. It rotates in 59 days, two-thirds of its year of 88 days. This makes its solar day, noon to noon, last two of its years. The European BepiColombo mission to orbit Mercury just made its first pass of the planet.
Addendum
Mercury and its apparent orbit for 7:49 am tomorrow, October 23, 2021, two days before its greatest western elongation (separation from the Sun). Created using Stellarium.
BepiColombo takes a picture of Mercury on its first of 6 flybys, October 1st, before settling into orbit of the planet on December 5, 2025. BepiColombo is actually two spacecraft connected together, and parts of the other spacecraft will get into each other’s images until they separate. Credit: ESA/JAXA.
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.
12/05/2019 – Ephemeris – Artemis the new Moon program
Ephemeris for Thursday, December 5th. Today the Sun will be up for 8 hours and 58 minutes, setting at 5:02, and it will rise tomorrow at 8:05. The Moon, 1 day past first quarter, will set at 2:01 tomorrow morning. | NASA has a new program to return to the Moon, perhaps to stay. The program is called Artemis, named after the Greek god Apollo’s twin sister. NASA is building a massive rocket called the Space Launch System, or SLS, and the Orion
, which I’m sure will guarantee European astronauts a ride. This is not going to be an Apollo type one rocket up and back. There will be a space station called the Lunar Gateway of International partners that will orbit the Moon. There the crew of the Orion Spacecraft will transfer to a Lunar Lander for the trip to and from the surface of the Moon. It’s a heavy push to accomplish by 2024.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Block 1b vrsion of the Space Launch System (SLS) which uses elongated Space Shuttle boosters and a core stage with 4 Space Shuttle main engines for the first stage. Credit NASA.
Cone-shaped Orion Multi-Purpose Crew Vehicle with a European Service Module. Credit NASA.
Lunar Gateway supplied by the same partners that built the International Space Station. It will orbit the Moon, Credit NASA.
Lunar Lander. This vehicle has not been designed yet. This is Blue Origin’s Ascent Module on top of a yet to be designed propulsion module. Credit Blue Origin.
11/04/2019 – Ephemeris – It’s a quarter Moon today. On the oceans the smallest difference between high and low tides.
Ephemeris for Monday, November 4th. Today the Sun will be up for 10 hours and 3 minutes, setting at 5:27, and it will rise tomorrow at 7:25. The Moon, at first quarter today, will set at 12:10 tomorrow morning.
Today’s first quarter moon means that this tides caused by the Moon and Sun are pulling on the Earth at right angles which keeps the tides low. These are called neap tides. The Moon also raises higher tides than the Sun, even though the Sun is much more massive. But it’s much farther away. And that’s the reason. Tides are caused by the difference in gravitational pull from one side to the other of the Earth. The Moon, being much closer has a greater difference in gravitational force. Only when the Moon Sun and Earth are lined up do we have the highest tides which are called spring tides. Galaxies, held together by gravity, are easily distorted by the tidal force of other galaxies and pull off what are called tidal tails.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Spring and Neap Tides explained. Credit http://www.millerslocal.co.za/the-inside-skinny-on-tides.html (South Africa).
This ground-based image was taken by Robert Gendler and shows the two merging Antennae Galaxies (NGC 4038 and NGC 4039) and their impressive long tidal tails. Click on the image to enlarge. Credit ESA.
09/12/2019 – Ephemeris – NASA and the Europeans plan to deflect an asteroid
Ephemeris for Thursday, September 12th. Today the Sun will be up for 12 hours and 41 minutes, setting at 7:59, and it will rise tomorrow at 7:19. The Moon, 2 days before full, will set at 6:30 tomorrow morning.
Meeting now in Rome is the AIDA International Conference. It has nothing to do with the opera, but a tortured acronym for Asteroid Impact Deflection Assessment. NASA and the European Space Agency are going to target the satellite of a binary near Earth asteroid Didymos. NASA will supply DART, the impactor, The Italians, a cube sat to fly along and record the impact. Later the Europeans will launch a probe to assess the asteroid deflection. Didymos itself is a half mile in diameter (2560 ft, 780 m), its satellite, a bit more than 500 feet (525 ft, 160 m). The impact should make a marked change in the small body’s orbit of its parent. DART’s launch should come in the summer of 2021 with impact in 2022.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Schematic of the DART mission shows the impact on the moonlet of asteroid (65803) Didymos. Post-impact observations from Earth-based optical telescopes and planetary radar would, in turn, measure the change in the moonlet’s orbit about the parent body. Credits and caption: NASA/Johns Hopkins Applied Physics Lab.
More information: https://www.universetoday.com/143313/europe-and-us-are-going-to-try-and-deflect-an-asteroid/
Bob Moler's Ephemeris Blog 