About these Notes
The following Astro-Landscape Photography Notes October 2018 is designed with the nightscape photographer in mind. I searched the web for information about astronomical objects that were presented in a condensed form that a landscape photographer could use to plan interesting photographs. When I couldn’t find any I liked, I made this list for myself. After putting all this together, I figured I’d put it on the web for others to use. So I expanded the scope to include information for a world-wide audience.
Please Note: All times are given in UTC, Coordinated Universal Time. Your local times may vary based on your location. If you’re unfamiliar with UTC, check out the excellent description at http://earthsky.org/astronomy-essentials/universal-time. Even with that information, it can sometimes be confusing converting UTC times to your local time. To help with that, try http://www.timebie.com/std/utc.php for converting specific a UTC time to your local time.
There are two highlights for this month –
- Three Visible Planets in a Row. Jupiter, Saturn, and Mars, in that order, will all be in a row across in the evening sky.
- Aurora season has returned.
This Months Articles
Have you ever wondered what’s up with the Kp Index numbers that people mention when talking about the aurora? See my article, “The Aurora K-Index“, below for a discussion of what these numbers mean and how to use them.
Finally, my Dark Sky Site of the Month is Bodmin Moor, England. Located in the Cornwall countryside, it is noted for stone walls, stone circles, and megalithic structures as well as some of the best dark skies in England.
Milky Way Core (MWC) Best Visibility – October 1st to 12th
The Milky Way Core is still visible world-wide, but it is only visible if the night sky gets dark enough to see it. The next deciding factor is the moon – if the moon is too bright or near the horizon, it washes out the sky giving poor MWC visibility. Interference from the moon does not change much with latitude. And third, the MWC is visible only in the evening hours now, setting well before midnight.
Nighttime by Latitude
True nighttime has returned to all northern latitudes this month. The long nights of winter have come to an end in the southern latitudes of Earth now that September Equinox has passed.
Nighttime Visibility by Latitude
|65° N||Nighttime has returned – more than 7 hours each night.|
|60° N||More than 7.5 hours all month.|
|55° N||About 8 hours all month.|
|40° N||More than 9 hours all month.|
|20° N||More than 9.5 hours all month.|
|Southern Hemisphere||Nighttime is getting shorter.|
|35° S||More than 7 hours all month.|
|50° S||More than 7 hours of at the start, but only 5 hours by months end.|
Milky Way Core (MWC) Visibility
There’s not much time left to photograph the Milky Way Core for this year. The Milky Way Core sets around 10 PM at the start of October for mid-northern latitudes. A waning Moon at the start of the month doesn’t interfere with MWC visibility, as the moon rises after the MWC sets. By the 13th, a waxing crescent Moon begins to interfere with visibility. After the 15th, the Moon washes out the MWC all evening until the last few days when the month. By the end of the month, the MWC will only be visible for around two hours.
Milky Way Core Visibility
45 N Latitude
|October 1-12||Best time for this month! MWC visible only from mid-evening until around midnight. Less than 90 minutes of visibility by the 12th.|
|October 13-14||Growing crescent moon begins to interfere with MWC visibility.|
|October 15-26||MWC not visible without the moon being up.|
|October 27-29||Only about 30 minutes of MWC visibility. Moon rising before midnight.|
|October 30||More than 2 hours of MWC visibility. Moon rising just before the MLC sets.|
35 S Latitude
|October 1-10||Best time for this month! Over 4 hours of MWC visibility.|
|October 11-14||The waxing crescent moon begins to interfere.|
|October 15-25||MWC not visible without the moon being up.|
|October 26-27||Less than 2 hours of MWC visibility. Moon rising before midnight.|
|October 28-31||More than 2 hours of MWC visibility. Moon rising near or after the MLC sets.|
October starts with a waning gibbous moon, about 6 days past full, rising around midnight. The new moon is on the 9th, so the first half of the month will have moonless evenings. By the 12th, a thin crescent moon appears in the evening sky. At month’s end, the moon is about 21 days old and is at last quarter.
|10/02 09:45 UTC||Third/Last Quarter||Waning Gibbous|
|10/09 03:47 UTC||New Moon|
|10/16 18:02 UTC||First Quarter||Waxing Gibbous|
|10/24 16:45 UTC||Full Moon|
|10/31 16:40 UTC||Third/Last Quarter||Waning Gibbous|
Lunar Trivia – American-Centric Traditional Moon Names for October
Supposedly from “Native Americans” of the NE and Eastern USA
|Hunter’s Moon – this year, the October full moon is named for wild game hunting in preparation for the coming winter. The Harvest Moon usually occurs in September, but about every three years it happens in October. The Harvest Moon is the only moon name that is determined by when it occurs, rather than the month in which it occurs. When the full moon occurs early in October, it is known as the Corn Moon.|
|Anglo-Saxon||St. Bede recorded in 725 CE, that the first full moon in October was called “Winterfylleth”, the “winter full moon,” as winter was said to begin on the first full moon in October.|
|Nothing of note.|
Highlights of the Month
|The End of Four Planets in a Row.||After several months with four bright planets in the evening sky, this will come to an end this month. Venus will dip into the sun’s glare and disappear from the evening sky. Hopefully you Astro-Landscape photogs out there captured a panoramic photo of this alignment. Venus, Jupiter, Saturn, and Mars are in that order from the sun. They will still all be in a row across in the evening sky, but with Venus low on the western horizon, it will be increasingly difficult to see as the days pass.
Don’t wait too long into the month. For those around 40° N Venus will be too low to see by October 7th, so don’t delay. At 35° S, Venus will disappear by mid-month.
|Saturn and Mars near the Milky Way Core||As in recent months, October offers a good opportunity to get planets in proximity to the Milky Way Core (MWC). Even though Jupiter is way off to the west now, and Mars and Saturn are still near the Milky Way Core. Mars is moving a little to the east from the MWC due to retrograde motion, but Saturn still nearly dead center to the MWC. It’s a great opportunity photographically.|
|Mercury||Mercury moves out of the Sun’s glare at the end of October. Look for it very low on the western horizon about 30 minutes after sunset. In the Southern Hemisphere, Mercury will actually be higher in the sky than Jupiter.|
|Venus||Venus heads into the glare of the sun by October 7th for those at 40° N and October 15th at 35° S. It heads to inferior conjunction with the Sun on October 26th. (An inferior conjunction is when either Mercury or Venus are on the same side of the sun as the Earth.)
By the end of October, Venus rises just before the sun and may be seen very low to the eastern horizon.
|Mars||Mars starts the month well above the southern horizon during blue hour at 40° N. It climbs higher into the sky as the month continues. It still shines brightly a bit east of the Milky Way Core. At 35° S, Mars is very high in the NE sky at the start of evening.
Like last month, Mars will lose about half of its brightness. Look for its distinctive red color. Hurry and catch it before it gets too dim to stand out.
The Martian Winter Solstice is on October 16th for the Martian northern hemisphere.
|Jupiter||Jupiter is still bright in the southwestern sky at the beginning of October, moving closer to the horizon as the month progresses. At mid-northern latitudes, it sets early in the evening at the beginning of October but only about an hour after the sun by the 31st.
At 35° S, Jupiter sets about 3 hours after sunset at the start of October but only about just more than an hour after sunset by the end of the month.
|Saturn||Saturn continue to rise along with the Milky Way Core through the entire month. It is highest in the sky at sunset and for an observer at 40° N it sets about a bit before midnight. By month’s end, it is setting closer to 9PM.
For southern hemisphere viewers, Saturn starts the evening high in the western sky by the end of the month it sets about 4 hours after sunset.
Saturn is still one of the brighter “stars” in the night sky.
Telescope: Even though the rings of Saturn are nearly a year past their maximum tilt, they are still an amazing sight to see. If you can view it through a telescope, look before it moves too far around the sun to get a good view.
|Uranus||Rising shortly after sunset and reaching its highest point in the night sky near midnight, Uranus reaches opposition on October 23rd.|
|Neptune||Rising in the southeast at sunset, Neptune is a little to the east of Mars and sets shortly after Mars.|
|Pluto||Really, if you don’t think Pluto is a planet, check out the photos from the New Horizons space probe. There are dunes of windblown methane ice crystals on it! https://www.nasa.gov/mission_pages/newhorizons/main/index.html
It’s located about halfway between Saturn and Mars. If you look in this area for a second or two, you’ll certainly have a few photons that travelled from Pluto hit your retina! But it’s only Magnitude 14 so you’ll need a big scope to see it as an actual point in the sky.
Note – The times given are for the closest approach. As the moon moves relatively quick across the sky, visibility of the closet approach will depend on your location.
|Date – UTC||Objects||Deg
|Moon Age||Moon Phase||Comments
Rating, 5=Best, 1=Worst
|2018-10-09 19:18||Moon + Mercury||4° 55′||O days||New Moon||In the Sun’s Glare.
1 out of 5
|2018-10-11 14:28||Moon + Jupiter||3° 30′||2 days||Waxing Crescent||Still not exciting.
4 out of 5
|2018-10-14 16:59||Moon + Saturn||1° 12′
|5 days||Waxing Crescent||Excellent.
1 out of 5
|2018-10-18 03:34||Moon + Mars||1° 54′||8 days||Waxing Gibbous||Not Bad.
2 out of 5
|None in July 2018|
Two Showers this Month
There are two meteor showers peaking at the end of October – the Orionids and the Southern Taurids. Coincidentally the both start on October 23rd! Neither one of these showers is expected to be spectacular…
Orionids – Peak October 21st
The Orionids are a medium strength shower but sometimes they do reach higher hourly rates. They typically produce about 25 meteors at maximum, but there have been several years (2006-2009) where 50-75 per hour were reached. Due to the conditions, expect to see about 10 per hour.
The Radiant is to the northeast of the star Betelgeuse in the constellation Orion. It lies in the SE skies for the Northern hemisphere and NE for Southern skies. This shower is associated with the famous Halley’s Comet.
However, this year the peak maximum is expected to occur during the afternoon hours for North America. In addition, a waxing gibbous, nearly full moon is up for much of the night. Try aiming your camera to the north with the moon behind you for the best chance to capture and meteors. The radiant is highest in the sky before sunrise.
Best Seen From: Either hemisphere
Maximum Hourly Rate = 25
Meteor Velocity = Swift – 41 miles/sec, 67 km/sec
Associated Comet = 1P/Halley. Yes, that Halley’s Comet.
Southern Taurid – Peak November 5th
If you see a meteor that’s not an Orionid in October, it is probably a Southern Taurid. Especially if it’s a fireball. They are a weak to medium strength shower. Southern Taurids typically produce at most 5 meteors per hour at maximum.
They are known for colorful fireballs which occur throughout the months of September, October, and November. In 2005 there was a Taurid fireball “swarm” with bright, slow-moving fireballs. The radiant is from the constellation Taurus.
Best Seen From: Either hemisphere
Maximum Hourly Rate = 5
Meteor Velocity = 17 miles/sec (slow) – 27km/sec
Associated Comet = 2P/Encke
For up to the minute aurora forecasts, check out the information at http://auroraforecast.gi.alaska.edu/ For animated forecast maps for both northern and southern hemisphere, try https://www.swpc.noaa.gov/products/aurora-30-minute-forecast
NOAA publishes a 27-day Outlook of Geomagnetic Indices While these are only predictions, they are based on the They are updated on every Monday at 1500 UTC and list the highest daily K values. As of the time of writing, it is predicting a minor to moderate storm event at Kp 6 on Oct 8th. Several days with Kp 4 or 5 activity are predicted as well.
As we approach the end of Solar Cycle 24 in the next, the outlook for solar activity that causes the aurora is expected to increase in the next several years. Despite the current Solar Cycle being very low in activity, aurora activity has been occasionally spectacular. Look for auroras to increase in the next few years. There was even a Kp5 (auroras are measured on a scale of 0 to 9) at the end of August, so even though we’re in a period of very low overall activity, there can still be occasionally high activity.
|Northern Hemisphere||Good – night skies are definitely dark enough for good viewing.|
|Southern Hemisphere||Still Good.|
“Night clouds” are a tenuous, cloud-like phenomena in the upper atmosphere. They are made of ice crystals and are only visible in a deep twilight. Noctilucent clouds are typically visible at higher latitudes in each hemisphere but can occasionally be seen at lower latitudes when the sun is well below the horizon.
|Northern Hemisphere from 50° to 70°||Not likely to be visible.|
|Southern Hemisphere from 50° to 70°||Opportunities are increasing as the sun’s path moves south. Look in the direction of where the sun is as it moves below the southern horizon.|
ISS and Satellites
Go to https://spotthestation.nasa.gov/ and sign up for flyover alerts. Usually show up about 12 hours before the flyover. These alerts tell the time, compass directions, angular elevation, and length of time of the flyover. Check for your location as the time of the flyover greatly affects the visibility of the ISS.
|Northern Hemisphere||It’s still a good time of year to see ISS flyovers even though the sun is moving further south.|
|Southern Hemisphere||Opportunities to see longer flyovers are increasing as the summer months are approaching.|
ISS Transits of the Sun or Moon
There is a possibility that the ISS will pass directly between any location on Earth and the Moon or the Sun. Transits are highly dependent on where the observer is located. And higher latitudes decrease the chances of these transits. The best way to find if a transit will happen nearby, go to https://transit-finder.com/
As the ISS is moving at about 17,000 mph (27,000 km/hr), transits happen quickly! Lasting from about 5 seconds to less than one second. Since these transits happen so quickly, you need to plan! Instead of trying to see the transit and then triggering your shutter by hand, have your camera set up and then either shoot HD or 4K video or have the camera shoot at it’s fastest frame rate. You’ll get more frames shooting video, especially if you have a camera that can shoot at 120 fps.
Since the Sun is so bright, make sure to use a solar filter that meets ISO 12312-2:2015 requirements for solar transits. The same filter that you got for the Great American Solar Eclipse last year will work well. Don’t trust your camera to a standard photographic ND filter as they will most likely not filter out Infrared light. You will risk frying your camera sensor by not having the proper filter.
|Nothing of note this month.|
The Aurora K-Index
When trying to predict auroras, it’s convenient to use a numbered index. To do this, space weather scientists, (yes, that’s an actual field of study), use what’s called the K-index. It’s a quasi-logarithmic scale, just like other scales you’re probably familiar with, such as the scales used to measure earthquakes (Richter magnitude), the pH scale for acidic and basic water solutions, or sound loudness (Decibel).
While it’s not important how K-values are calculated, they use measurements of Earth’s magnetic field and its interaction with charged particles from the sun that have been blown off in the solar wind. This index gives us an easy way to talk about the global level of geomagnetic activity. And the cool thing for Astro-Landscape photographers, more geomagnetic activity means more intense auroras.
The K-index ranges from 0 to 9 and is always a whole number. The larger the number, the more the earth’s magnetic field has been disturbed. That means there are more charged particles coming from the sun that will be funneled by the earth’s magnetic field towards the North and South Poles. When these particles hit the earth’s upper atmosphere, they interact with oxygen and nitrogen molecules and light up the sky with an aurora.
Indices from 0 to 2 typically show no or little aurora activity. Kp 2 activity is categorized as “Unsettled”, and by the time is rises to Kp 3 it’s called “Active”. From Kp 4 and up, K-indices are called storms and can affect radio communications. Starting with Kp 4 and 5 as a “Minor Storm” and Kp 6 as a “Moderate Storm”, aurora activity starts to really pick up in this range. Once the index gets to Kp 7 and higher, geomagnetic activity is called “Strong”, “Severe”, and “Extreme” storms. K-indices at the highest levels of the scale can affect sensitive electronics and power distribution. Storms this strong have caused regional power outages in recent decades.
So, what does this mean for the Astro-Landscape photographer? It means you can better understand aurora predictions by knowing what to expect when Kp values increase. There are a few basic things to remember – as the Kp index increases, the intensity of the aurora increases and the lowest latitude that the aurora is visible moves south. This means that the aurora covers a larger area of the earth’s surface as the Kp number increases.
As a guideline for Europe, a Kp 2 or 3 aurora should be visible in Iceland. A Kp 4 may be visible in the Faroes and a Kp 5 could be visible down to Scotland, southern Norway or Sweden, and all of Finland. A Kp 6 could reach Ireland and northern England, Denmark, and the Baltic States. It could take a Kp 7 to get down to southern England, the Netherlands, northern Germany and Poland. A Kp 8 would be needed to reach France or the Czech Republic. And a Kp 9 might get all the way down to Italy. A map can be seen at: http://www.aurora-service.eu/aurora-school/all-about-the-kp-index/
For North America, a Kp 3 may reach down to the Canadian-USA boarder just north of Minnesota. A Kp 5 may cover nearly all of Canada, except for a bit of British Columbia, southern Ontario, Nova Scotia, and Newfoundland. The Kp 5 could dip into the northern Midwest of the USA. A Kp 7 might be seen from Washington State across to Iowa and then over to New York and New England. Finally, a Kp 9 may cover all of Oregon to Missouri and the Virginias. A map can be seen at: http://www.aurora-service.org/
In the Southern Hemisphere, Antarctica is by far the best location to see the aurora. The South Island of New Zealand may begin to see auroras starting at about Kp 5. But a Kp 8 or 9 may be visible across all New Zealand and even the southern lands of Australia. Only the strongest of geomagnetic storms would be seen in the southern tips of South Africa and South America since they are so far away from the geomagnetic south pole.
Japan, Korea, and China are generally too far south for see the aurora.
It’s not only about the K-Index
Now, with all that said, when and where an aurora is visible is highly dependent on the solar wind and, of course, the position of the sun. A high Kp value will not matter if it happens during daylight hours. And the Kp index doesn’t correspond to a specific location on a map where an aurora will be visible, it’s just a guideline for intensity. Since there’s a lot of variables at play, sometimes, you can get lucky. If you’re located in a place that usually gets auroras at Kp 5, go out look when a Kp 4 is predicted. Find a location with dark skies and an unobscured view to the north. If you look along the northern horizon, you may see the aurora.
Dark Sky Locations
Bodmin Moor Dark Sky Landscape (England)
This month I’ve picked a location in the county of Cornwall, in the most southwest region of England, the Bodmin Moor Dark Sky Landscape. http://darksky.org/idsp/parks/bodminmoor/ Bodmin Moor is rugged and remote, it’s a granite upland that is treeless, exposed, and sometimes desolate. Since it has some of the darkest skies in the British Isles, it has been designated a “Dark Sky Park”. It’s less than 250 miles from London, a bit more than 4 hours from the center of London via the M4, M5, and A30.
Bodmin Moor is the largest unit of the Cornwall Area of Outstanding Natural Beauty (AONB). An AONB is a countryside area which has been designated for conservation due to its national importance and landscape value in England, Wales, or Northern Ireland. Of the twelve units in the Cornwall AONB, Bodmin Moor is the only one that is not on the amazing Cornwall coastline. Bodmin Moor was the first AONB to receive accreditation by the International Dark Sky Association for it’s dark skies.
A Class 4 Bortle Rating
Bodmin Moor is in a Class 4 Rural/Suburban (Dark Green) location on the Bortle Scale. At around 1000 ft / 330 m elevation, Bodmin Moor is the highest point in Cornwall which helps with visibility. Colliford Lake is recognized as an excellent sky gazing spots.
Cornwall has one of the sunniest and mildest climates in the United Kingdom, due to its coastal setting and the influence of the Gulf Stream. However, summer temperatures are not as warm as other parts of southern England, again due to the ocean influence.
As with much of England, lodging is available nearby.
There’s More than Just the Moor!
Bodmin Moor has several locations that will be of interest to the Astro-Landscape photographer. There are several stone circles, stone rows, and megalithic monuments in the area. Granite outcroppings and tors litter the hills. Brown Willy, the highest point in Cornwall, has a large cairn at the summit as well as an Ordinance Survey triangulation station nearby. Outside of the Moor, Cornwall has numerous photogenic seascapes and the remains of Tintagel Castle, reputed to be King Arthur’s birthplace!
International Dark Sky Association
Dark Sky locations help greatly with photographing the Milky Way. To help readers of this blog, I’m listing a dark sky location each month that readers might be interested in visiting. For more information, I’d like to recommend visiting the International Dark-Sky Association (IDA) website at http://darksky.org/about/ The IDA maintains a list of some of the world’s best dark sky locations. They are also dedicated to educating people about light pollution and how to reduce it.
If you find any info that needs clarification or correction for this Astro-Landscape Note, please email me at firstname.lastname@example.org.