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Ephemeris: 11/12/2024 – SpaceX uses Cargo Dragon to change orbit of the ISS
This is Bob Moler with Ephemeris for Tuesday, November 12th. Today the Sun will be up for 9 hours and 40 minutes, setting at 5:17, and it will rise tomorrow at 7:37. The Moon, halfway from first quarter to full, will set at 4:39 tomorrow morning.
After the last SpaceX cargo mission arrived at the International Space Station, they used the thrusters on the SpaceX capsule to raise the orbital space station a little bit as a test. SpaceX capsules dock at the forward end of the space station according to direction of travel so in order to boost the station’s orbit they had to flip the station around so that the docking port was at the rear before they could apply the needed thrust. When thrust is applied to an object in orbit the effect of the change occurs mostly at the opposite side of the orbit. In order to permanently raise or lower an object’s circular orbit one must make 2 adjustments 180° away from each other. This is the essence of the Hohmann Transfer Orbit, proposed by German scientist Walter Hohmann in 1925.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations
Addendum
Ephemeris: 08/27/2024 – Space news
Sorry, about posting this late. I was working on our astronomical society article and newsletter. The article will be posted as an Ephemeris Extra in a couple of weeks. For a preview see my August 22nd post.
This is Ephemeris for Tuesday, August 27th. Today the Sun will be up for 13 hours and 27 minutes, setting at 8:27, and it will rise tomorrow at 7:01. The Moon, 1 day past last quarter, will rise at 12:55 tomorrow morning.
Let’s take a look at some space news. Today is the first day of the launch window for the SpaceX commercial mission Polaris Dawn where 4 private astronauts will ride a SpaceX Dragon capsule to the highest point astronauts have been since the Apollo days, some 1400 kilometers or 870 miles above the Earth. They will also perform the first commercial EVA or space walk. Two of the astronauts will take turns poking their body out the hatch capsule for a short period of time. They will not be free floating, but they will be connected to the capsule by foot or hand restraints.
In other news NASA has decided to bring Suni Williams and Butch Wilmore, the Boeing Starliner test astronauts, back to Earth on a Dragon capsule in February due to safety concerns.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT–4 hours). Times will be different for other locations.
Addendum
Ephemeris: 06/10/2024 – Finding Draco the Dragon
This is Ephemeris for Monday, June 10th. Today the Sun will be up for 15 hours and 31 minutes, setting at 9:28, and it will rise tomorrow at 5:56. The Moon, halfway from new to first quarter, will set at 1:09 tomorrow morning.
High in the northern sky at 11 p.m. lies the twisted constellation, that of Draco the dragon. This dragon is more like the snakelike Chinese dragon than the dinosaur-like dragon of European legend. I find it better to start at the tail of Draco, to trace him out in the stars. Draco’s tail starts, or ends, between the bowl of the Big Dipper and the Little Dipper high in the north-northwest. The Dragon is seen in a line of stars that extends parallel to the handle of the Big Dipper before curving around the bowl of the Little Dipper then bends back down to the level of Polaris in the north-northeast before turning toward the east. The head of Draco is an odd box of stars near the bright star Vega, high in the east. Though not made up of very bright stars, Draco has an easy shape to trace.
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
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.
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