Archive
08/03/2020 – Ephemeris – What is the Perseverance Rover going to do on Mars?
This is Ephemeris for Monday, August 3rd. Today the Sun will be up for 14 hours and 33 minutes, setting at 9:05, and it will rise tomorrow at 6:33. The Moon, at full today, will rise at 9:35 this evening.
The Mars Perseverance Rover looks a lot like the Curiosity Rover that landed on Mars in Gale Crater almost exactly 8 years ago (Earth years that is). It has more and better cameras, some different tools on its arm. It will have a laser like Curiosity. It can take core samples and store them in sealed tubes for later return to the Earth. It has an experimental helicopter drone named Ingenuity that must, like the rover be autonomous since it cannot be controlled in real-time from the Earth. The main mission this time is to look for signs of life in a spot we know water had flowed in the ancient past. The surface water and the life is long gone, but there might be signs that it might have been present in the distant past before Mars lost most of its atmosphere and water.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Artist rendition of the Mars 2020 “Endurance” Rover. Credit NASA.
Artist’s concept of the Mars Helicopter “Ingenuity”. Credit: NASA/JPL-Caltech.
07/30/2020 – Ephemeris – This morning is the first opportunity to launch the Perseverance Rover to Mars
This is Ephemeris for Thursday, July 30th. Today the Sun will be up for 14 hours and 42 minutes, setting at 9:10, and it will rise tomorrow at 6:28. The Moon, 3 days past first quarter, will set at 3:11 tomorrow morning.
This morning is the scheduled launch of the Mars 2020 Rover named Perseverance. The launch will have or had launched at 7:50 am. Or the whole thing was scrubbed for today. I can’t tell, I recorded this last Sunday night. To hit a spot on Mars less than six miles in diameter after a six and a half month coasting flight is quite a fete. Mars is not only moving in orbit of the Sun, but also rotating. The aeroshell the rover is packed in must hit the Mars atmosphere in the right place, and the right time despite the light time from Mars of 11 minutes, 22 seconds. It will take 6 minutes, 50 seconds for the rover to land after it hits the top of Mars’ atmosphere. So it will have landed one way or another before we get the signal that it hit the atmosphere.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Atlas V with Mars 2020 Rover aboard on launch pad. Click on the image to enlarge. Credit: United Launch Alliance (ULA).
07/28/2020 – Ephemeris – The Mars Endurance Rover may launch to Mars on Thursday
This is Ephemeris for Tuesday, July 28th. Today the Sun will be up for 14 hours and 47 minutes, setting at 9:12, and it will rise tomorrow at 6:26. The Moon, 1 day past first quarter, will set at 1:49 tomorrow morning.
This Thursday at 7:50 am is the first opportunity to launch the Mars 2020 or Perseverance Rover to Mars to arrive on February 18th 2021. The rover will be launched on a United Launch Alliance Atlas 5/Centaur rocket with 4 solid boosters. To send a payload to Mars one must launch within a specific window of time called a launch period. This was originally from July17 to August 11th. Some issues with testing caused a delay to July 30th. The launch period was extended to August 15th. Miss that and it’s a wait of 26 months until Earth and Mars are in the same relative position to try again. The landing area or ellipse is less than 6 miles long on the long axis and partially overlaps an ancient dried river delta that flowed into Jezero crater.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
An artist’s concept of the Mars 2020 Rover launch. The rocket is an Atlas V with 4 solid boosters and a Centaur upper stage. Credit NASA.
05/26/2020 – Ephemeris – The first launch of humans to orbit from American soil in 9 years could happen tomorrow
This is Ephemeris for Tuesday, May 26th. Today the Sun will be up for 15 hours and 12 minutes, setting at 9:16, and it will rise tomorrow at 6:03. The Moon, 3 days before first quarter, will set at 1:07 tomorrow morning.
As of Sunday when I’m recording this NASA and SpaceX are still GO for the launch of two American astronauts to the International Space Station tomorrow. This will be the first human launch from the United States since Space Shuttle Atlantis left this same launch pad 39a left on July 8th, 2011. On that flight Doug Hurley was pilot, and he will command this flight. He visited the ISS twice, however his wife Karen Nyberg also visited the ISS twice, however the last time she stayed nearly 6 months. Bob Behnken the second astronaut is also a space shuttle veteran with two construction flights to the ISS and like Hurley is married to an astronaut, Megan McArthur who flew on the last Hubble Space Telescope repair mission.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
SpaceX Demo-2 astronauts Bob Behnken (left) and Doug Hurley. Credit: SpaceX.
05/25/2020 – Ephemeris – Comet SWAN is in our skies in evening twilight
When I recorded this program on the evening of the17th there was hope that Comet SWAN would have achieved naked-eye visibility. It did earlier this month when it was too far south for us to see from 45° North latitude. Predictions now are for it to be 7th magnitude, 2.5 times dimmer than the faintest star visible to the unaided eye.
This is Ephemeris for Memorial Day, Monday, May 25th. Today the Sun will be up for 15 hours and 10 minutes, setting at 9:15, and it will rise tomorrow at 6:03. The Moon, 3 days past new, will set at 12:18 tomorrow morning.
Comet SWAN just might be visible in binoculars tonight by about 10:30 p.m. with binoculars or a small telescope low in the northwestern sky. A pointer to it is the bright star Capella also in that direction. Comet SWAN will be located in the direction of 4 o’clock (to the right and a bit down) by 10 degrees angle, the width of your fist held at arms length. It will be a small fuzzy spot. I doubt you would spot the comet’s tail. It is a thin ion or gaseous tail that is revealed in photographs only. Over the next week it will be moving toward Capella and on June 1st will be just below Capella but half as bright as it is now. There’s another comet coming. Comet NeoWISE will be visible in our skies by late July if it holds up.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addenda
Comet SWAN
Comet SWAN track against the stars for 10 pm May 25 to June 3, 2020 with Mercury and Venus for the 25th They will be moving too. Comet labels show month-day and magnitude. However add 4 to the magnitude to get the approximate actual magnitude. The comet would be hard to spot in binoculars even in a dark sky. But who knows, the comet might flare up and be visible. Created using Cartes du Ciel (Sky Charts).
Northwestern horizon tonight at 10 pm May 25, 2020 with a scale that’s close to that of the image above. The comet is not bright enough to show here. Created using Stellarium.
In Memoriam
Today as we prepare to send humans into space from American soil for the first time in 9 years we pause to remember those who gave their lives for our country. For purposes of this program that includes those courageous enough to sit on top of or beside a million pounds of explosives to be launched into space. From the three astronauts who died in the Apollo one file in 1967, the explosion of the Space Shuttle Challenger in 1986, to the disintegration of the Columbia in 2003, 17 Americans and other nationals have died in NASA space accidents. The Russians too have lost cosmonauts in the exploration of space. Brothers and sisters in the quest for knowledge and to expand the horizons of human habitation. Per aspera, ad astra, Through difficulties to the stars!
A listing of Astronaut and Cosmonaut deaths: http://www.aerospaceweb.org/question/history/q0114.shtml
The Vatican Observatory Calendar
Being Catholic, I occasionally check the Vatican Observatory Foundation website. Besides the director of the Vatican Observatory is Brother Guy Consolmagno SJ, a fellow Michigander, born in Detroit. There were a couple of items on the May calendar that caught my eye.
Today, was marked as Memorial Day, but also Towel Day. Towel Day? It’s the 42nd anniversary of the first BBC Radio broadcast of Douglas Adams’ Hitchhiker’s Guide to the Galaxy. And if you don’t know the significance of a towel or the number 42, I won’t spoil it for you.
Also May 15th was the 300th birthday of Maximilian Hell SJ, first director of the Vienna Observatory, who also observed the transit of Venus in1769 from northern Norway. The crater on the Moon Hell is named for him. I’ve always had fun showing the crater a day or two after first quarter and mentioning that the crater Hell is named after a priest.
05/08/2020 – Ephemeris – A look at Mars 2020 Endurance Rover’s target crater: Jezero
This is Ephemeris for Friday, May 8th. Today the Sun will be up for 14 hours and 34 minutes, setting at 8:56, and it will rise tomorrow at 6:21. The Moon, 1 day past full, will rise at 10:43 this evening.
The Mars 2020 Rover will be launched on July 17th or thereabouts to land at the crater Jezero* on the Red Planet. What’s the big deal about Jezero? In very early Martian history the crater was filled with water with a river flowing into it. What’s left is a dry river delta. The landing ellipse target for the rover will land it near the leading edge of that delta. Spectral analysis from the Mars Reconnaissance Orbiter has detected clays that can contain, on Earth, fossils of single celled organisms. The rover is not equipped with a powerful enough microscope to detect them so they will be cached to be returned to the Earth sometime in the future as one of its objectives. Scientists believe that Mars was friendly for life for only a billion years or so.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jezero is pronounced like the biblical character Jezebel.
Jezero Crater on a map by the Mars Orbiter Laser Altimeter (MOLA) instrument on the Mars Global Surveyor spacecraft (1996-2006). Colors code by altitude (blue-low to red-high). Click on the image to enlarge. Credit NASA/JPL.
The Jezero crater from the European Space Agency’s Mars Express Orbiter. Jezero is 30.4 miles (49.0 km) in diameter. Note the river delta on the left (west) forming a lake with an outlet on the right. Click on the image to enlarge. Credit: NASA/JPL/MSSS/ESA.
Mars Endurance Rover’s planned landing ellipse partially overlapping the dried up river delta. Click on the image to enlarge. Credit: NASA/JPL.
Delta of ancient river that flowed into a lake in the Jezero crater. Color coded based on minerals present. Click on the image to enlarge. Credit NASA.
05/07/2020 – Ephemeris – JPL and NASA preparing a return to Mars via rover and helicopter
This is Ephemeris for Thursday, May 7th. Today the Sun will be up for 14 hours and 32 minutes, setting at 8:55, and it will rise tomorrow at 6:22. The Moon, at full today, will rise at 9:26 this evening.
The Endurance Mars Rover will be launched on or after July 17th. To land on Mars February 18th next year. It has until August 5th to launch. That’s a 20 day launch window. Miss that and it’s a wait of approximately 26 months for the next launch window when the Earth and Mars get into the proper relative positions again. The target of the rover is Jezero crater at the edge of a large Martian feature that can be seen in small telescopes called Syrtis Major. Syrtis Major is cooler sounding than what it means in Latin… The Great Swamp*. Anyway, Jezero crater itself is named after a Bosnian town in 2007 by the International Astronomical Union which named interesting features on Mars after earthly towns. What’s so interesting about Jezero? The answer tomorrow.
* There’s no water there. It’s actually a volcanic plain, maybe a low shield volcano.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Artist rendition of the Mars 2020 “Endurance” Rover. Credit NASA.
Artist’s concept of the Mars Helicopter “Ingenuity”. Credit: NASA/JPL-Caltech.
Jezero Crater on a map by the Mars Orbiter Laser Altimeter (MOLA) instrument on the Mars Global Surveyor spacecraft (1996-2006). Colors code by altitude (blue-low to red-high). Click on the image to enlarge. I’ll have a closer look tomorrow. Credit NASA/JPL with my labels.
05/05/2020 – Ephemeris – SpaceX’s Commercial Crew Demo 2 mission extends to multi-months
This is Ephemeris for Tuesday, May 5th. Today the Sun will be up for 14 hours and 26 minutes, setting at 8:53, and it will rise tomorrow at 6:25. The Moon, 2 days before full, will set at 6:15 tomorrow morning.
On May 27th* or shortly thereafter the first crewed spacecraft will leave American soil since the last Space Shuttle launch in 2011. This is called the SpaceX Demo 2. Notice they’re not called manned spacecraft any more. Especially since the American with the most time in space, man or woman is Peggy Whitson with nearly 666 days in space over three flights to the International Space Station. NASA astronauts Bob Behnken and Doug Hurley will launch from historic Pad 39a at the Kennedy Space Center on a Falcon 9 rocket in a Crew Dragon spacecraft to the International Space Station. What was to be a two week stay will turn out to be a several month tour on the station.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
* The date I gave in the program was the 25th.
Addendum
Crew Dragon atop the Falcon 9 and Crew access arm. Credit SpaceX.
Astronaut humor.
Bob Behnken and Doug Hurley, NASA Astronauts for Demo-2 of SpaceX Crew Dragon. Credit: NASA. Each has had two flights on the Space Shuttle. Hurley was Shuttle Pilot twice. Credit NASA.
03/09/2020 – A NASA mission to the Trojans, strange asteroids in Jupiter’s orbit
Ephemeris for Monday, March 9th. Today the Sun will be up for 11 hours and 36 minutes, setting at 7:41, and it will rise tomorrow at 8:03. The Moon, at full today, will rise at 7:46 this evening.
Lucy is a NASA mission (https://www.nasa.gov/content/goddard/lucy-the-first-mission-to-jupiter-s-trojans) whose name is not some tortured acronym. It is named for a Beatles tune and a hominid fossil found in Africa. It will set off in October next year to study two groups of strange asteroids, Jupiter’s Trojan asteroids. These asteroids lie in two swarms in Jupiter’s orbit averaging 60 degrees ahead and 60 degrees behind Jupiter. They congregate around two gravitational points in the Jupiter-Sun system called Lagrangian points, specifically L4 ahead of Jupiter and L5 behind. The Lucy spacecraft will put itself in such an orbit that it can loop between the Earth’s orbit and each of the two Trojan swarms passing by several of the asteroids. In general the names given to the asteroids are for the characters from Homer’s Iliad. The L4 group named or the Greeks and the L5 group named for the Trojans. I’ll be visiting this mission and that of Trojan asteroids in the future. The Earth actually has one known Trojan asteroid.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum:
The inner solar system with Jupiter’s Trojan asteroids. The Hilda asteroids have orbital periods of 2/3rds Jupiter’s period. Their elliptical orbits rise from the asteroid belt (white dots) to the L3, L4 and L5 points respectively. Credit: Mdf at English Wikipedia.
The 5 Lagrange points about two bodies orbiting each other. The Lagrange or Lagrangian points of gravitational equilibrium were discovered by Joseph-Louis Lagrange (1736-1813). Credit Georgia State University.
12/30/2019 – Ephemeris – Some space advances this year
Ephemeris for Monday, December 30th. Today the Sun will be up for 8 hours and 50 minutes, setting at 5:10, and it will rise tomorrow at 8:20. The Moon, 3 days before first quarter, will set at 9:45 this evening.
Let’s look back at space activity this past year. SpaceX launched its Falcon Heavy rocket twice successfully for commercial payloads. It also performed the Demo 1 flight to send a uncrewed Dragon 2 to the International Space Station. That went off without a hitch. However when testing the same capsule a month later it was destroyed in a fueling mishap that postponed further flight tests until next month. The other Commercial Crew contractor Boeing was having problems with its Star Liner capsule. The latest being a mishap with their test flight to dock with the ISS. Supposedly a timing malfunction caused it to use too much fuel, so it ended in the wrong orbit. However it did land safely.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
A SpaceX Falcon Heavy rocket, carrying the U.S. Air Force’s Space Test Program 2 Mission, lifts off from the Kennedy Space Center in Cape Canaveral, Florida, U.S., June 25, 2019. REUTERS/Joe Skipper
The Demo 1 Dragon docking with the International Space Station. Credit NASA
Starliner Orbital Test Launch on an Atlas 5. Credit Boeing.
Bob Moler's Ephemeris Blog 