Archive for October 6, 2020

10/06/2020 – Ephemeris – Mars is closest today, also the Draconid meteors are at peak

October 6, 2020 Comments off

This is Ephemeris for Tuesday, October 6th. Today the Sun will be up for 11 hours and 25 minutes, setting at 7:13, and it will rise tomorrow at 7:48. The Moon, 3 days before last quarter, will rise at 9:46 this evening.

Today Mars is at its closest to the Earth of this close approach, what astronomers call an apparition. The last close approach was at the end of July two years ago. It is still pretty small in telescopes. However being this close, 38.6 million miles (62.1 million kilometers) away, it is actually slightly brighter than Jupiter. Check them out. Mars is the bright orange tinged star in the east while Jupiter is in the south-southwest at 9 pm tonight. It’s still a week before Mars lines up with the Earth and Sun in opposition. Mars is closer now because it is moving away from the Sun in its orbit. We are at the peak of a weak meteor shower most years. It’s the Draconids, which appear to come from the head of Draco the dragon near the bright star Vega, nearly overhead in the evening.

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



Inner solar system on October 6, 2020 showing Mars at it’s closest to the Earth. Note the motion of the planets and space probes are counterclockwise. Mars is moving away from its closest point to the Sun at about the 2 o’clock point in its orbit. Note that at this time Mars, the Earth and Sun are not yet in line, so Mars isn’t directly opposite the Sun from the Earth, called opposition. That will occur on the 13th. The Mars 2020 Rover “Percy” has a bit more than 4 months to go to reach Mars. Credit: NASA Eyes App

Draconid Meteor Shower

The Draconid radiant in the head of Draco. Looking high in the northwest at 9 pm October 6th. The source of the Draconids is the Comet 21P/Giacobini-Zinner. The stars of the Summer Triangle are named.

Comet Giacobini-Zinner was the third comet I had ever seen. It was through my newly completed 8″ reflector in 1959, when the comet was quite close to the Earth. The comet just skims the Earth’s orbit at its perihelion, so the Earth passes through its trail of debris each year at this time. The meteor shower is very weak, 5-10 meteors an hour, unless the comet is near to the Earth at the time, as it was in 2018. The comet has an orbital period of about 6.6 years, so this year’s peak isn’t supposed to be the best. However this year me might have two mini peaks tonight in the 9 to 10 pm hour as the Earth is expected to pass through two old meteoroid trails. according to the International Meteor Organization’s 2020 Meteor Shower Calendar we are expected to pass through the 1704 trail at 9:25 pm, EDT and the 1711 trail at 9:57 pm EDT. This is October 7th at 1:25 UT and 1:57 UT. The normal projected peak is October 8 at 12:30 UT, that’s Thursday at 8:30 am, after sunrise.