Astroblog

 

 You may have seen the rather breathless statements about the up coming planetary lineup (or planet parade) often illustrated with telescope images of the planets all rather close together and claiming 6-7 planets will be present in the evening sky. 

While this is (mostly) true, you won't see anything like the illustrations. The hype distracts from what is a beautiful phenomenon.The planets, only 4 of which are bright dots, are strung out from west to east along the ecliptic like beads on a wire, Jupiter and Mars are bright and in some beautiful night sky territory. 

I have some charts and spotting tips below to help you enjoy this without the hype.

Evening sky on Saturday, January 18 as seen from Adelaide at 21:34 ACDST (60 minutes after sunset, Similar views will be seen from the rest of Australia at roughly the equivalent local time, click to embiggen)	Evening sky on Saturday, January 25 as seen from Adelaide at 21:30 ACDST (60 minutes after sunset, Similar views will be seen from the rest of Australia at roughly the equivalent local time, click to embiggen)	Evening sky on Friday, February 28 as seen from Adelaide at 20:20 ACDST (30 minutes after sunset, Similar views will be seen from the rest of Australia at roughly the equivalent local time, click to embiggen)
Orientation of the inner planets on Saturday, January 18 as seen from above the plane of the solar system	Orientation of the inner planets on Saturday, January 25 as seen from above the plane of the solar system	Orientation of the inner planets on Friday, February 28 as seen from above the plane of the solar system
Orientation of the outer planets on Saturday, January 18 as seen from above the plane of the solar system	Orientation of the outer planets on Saturday, January 25 as seen from above the plane of the solar system	Orientation of the outer planets on Friday, February 28 as seen from above the plane of the solar system

Basically, you can only see 4 of the 6-7 with your unaided eye, and rather than all being scrunched up close together, they are spread out over most of the sky from west to north-east.

From the 18th of January to mid February,  face west, looking 60 minutes after sunset. Venus is obvious above the western horizon as the brightest object in the sky. Much dimmer Saturn is a spark just above obvious Venus. Turning to the north the next brightest object is golden Jupiter, the second brightest object in the sky after Venus, just below bright red star Aldebaran and the "V" of the Hyades, not far from the delightful Pleiades cluster. Then looking towards the north east, bright red Mars, just past opposition and the third brightest object in the sky, just edging out the bright star Sirius, is lined up with the pair of stars Castor and Pollux, in Gemini. Neptune is telescope visible only and will be difficult to see low on the horizon (see charts above). 

Uranus is theoretically unaided eye visible under dark sky sites if you know where to look but is best with binoculars or telescope. Uranus is 3° above delta Ari and roughly halfway between Alpha Ceti and the Pleiades (see chart to the left), it is relatively easy to find in binoculars.

The black and white chart suitable for printing shows the location of Uranus, the circle is the approximate field of view of 10x50 binoculars.

The best times to look are between 60 minutes (nautical twilight) and 90 minutes (astronomical twilight, when the sky is fully dark) after sunset, and it helps if you have a clear and level western horizon. Although Venus and Saturn set about 30 minutes or so after astronomical twilight, ~ 2 hours after sunset, trees and houses tend to get in the way. 

You should be able to see this lineup from now until around 15 February, when Saturn is too low in the twilight to see (although you should be able to see it with binoculars). 

After January the 18th, Saturn draws away from Saturn as the pair lower in the evening twilight. On February the first the crescent Moon is between Saturn and the obvious bright Venus low above the western horizon 60 minutes after sunset. The Moon then goes on to visit all the bright planets in turn over the next few days, this will look very nice . Venus is at its greatest brilliance on the 15th of February. 

Although Jupiter and Mars move somewhat over this time they will be roughly where they are on the 18th of January, although Mars is fading rapidly.

Mercury Joins the line up around February the 15th, making 7 planets present, but is hard to see very low in the twilight. By Feb 28 Mercury is higher, but it, Saturn and Neptune are too deep in the twilight to see, and Venus is marginal. Binoculars will be required to see Mercury, and possibly Venus, which is now a thin crescent. 

So ignore the hype and head out in the early evening to enjoy the sight as well the constellation of Orion and bright Sirius  in Canis Major are there to look at too.

 

Labels: alignment, binocular, Jupiter, Mars, public outreach, Saturn, unaided eye, Venus

Morning sky at 5:44 ACST (60 minutes minutes before sunrise) facing east as seen from Adelaide on Tuesday, April 14.	Morning sky at 5:44 ACST (60 minutes minutes before sunrise) facing east as seen from Adelaide on Wednesday, April 15.
Morning sky at 5:45 ACDST (60 minutes minutes before sunrise) facing east as seen from Adelaide on Thursday, April 16	Morning sky at 5:46 ACDST (60 minutes minutes before sunrise) facing east as seen from Adelaide on Friday, April 17

The next four days offers some excellent sky viewing if you are prepared to get up in the early hours.

Staring tomorrow morning the Moon climbs down the ladder of planets. On Tuesday the 14th the waning Moon aligns with the four bright planets, on Wednesday the 15th the last quarter Moon is close to Jupiter, on Thursday the 14th the crescent Moon is between Saturn and Mars and finally on the Friday 17th the crescent Moon lines up with the planets again.

On the 22nd Mercury and the thin crescent Moon will be difficult to see low in the twilight.

On the 15th the Moon and Jupiter are in binocular range, but sadly not in telescope range. 

Labels: alignment, Jupiter, Mars, Mercury, Moon, Saturn, unaided eye

From bottom to top, Venus, Mercury, Jupiter and the Moon on the evening of 6 August (Canon IXUS ASA 400, 1 second exposure) Click to embigen.	From bottom to top, Venus, Mercury, Jupiter and the Moon on the evening of 7 August (Canon IXUS ASA 400, 1 second exposure) Click to embigen.

After being clouded/rained out on the early pat of the Planet Dance (4th and 5th), the 6th and 7th were clear, the 6th stunningly so. Had to go out to the opera on the 6th (the Co-opera group which gave a recital of "The Clemency of Tito" at the Port Adelaide Flour Warehouse - not a high culture event) so I couldn't get images of the Moon and Jupiter close together.

The colours in the sky on Saturday the 6th were stunning, on Sunday the 7th there was a lot of horizon cloud, nd I had to wait until a bit later for Venus to come out from behind the cloud, so the effect was not as pronounced.

Labels: alignment, Jupiter, Mercury, Moon, Venus

Planets as seen at the time of the Carrington Event, this is not much of an alignment (simulated in Celestia, click to embiggen)

Hot on the heels of claims about alignments and earthquakes, comes the notion that planetary alignments are associated with solar flares. A recent video points out that the Carrington event, the most massive solar flare ever recorded, occurred during an "alignment" (see also here). It then goes on to draw a very long bow to try and associate solar flares with planetary alignments.

Again, people apparently think that because planets are large, they will have significant gravitational/tidal effects that might affect the Sun, but as we have previously seen,  these effects fall off rapidly with distance, with Venus having less than a millionth of the tidal force of the Moon, for example.

The problem is that, during a solar maximum, there are a lot of flares. There are also a lot of alignments (depending on how you define alignment, well get to that later). By chance alone you would expect to see flares and alignments overlap occasionally.  

Planets as seen at the time of the1989 Event, which blacked out much of Canada. No alignment (simulated in Celestia, click to embiggen) 

How frequent are flares? Well, it depends on the size of the flare and the time. The rarest and most powerful events are the X-class flares (the Carrington Event was a super X flare), and we have the most of these during solar maximum.

According to this document, there is an average of one X-class flare a month during solar maximum (which would mean that alignments and flares would pretty well occur often by chance alone). M and C class flares are even more common, the amount of data makes it hard to work with.

Of course, the flares are not evenly distributed, with far more occurring during the peak years than the start years.

I've approached the issue of alignments and flares in two ways.

1. I've taken the list of most powerful X class flares since 1976 and looked at whether there were alignments close to or during these times.
2. I've looked at all alignments during the 2001-2003 solar maximum, when there were the most X-class flares, and looked to see if they are significantly associated with flares.

This brings us to what constitutes an "alignment". In astronomical terms two or more objects are considered aligned if they are within 5º of each other. 5º represents the width of the top of your hand as seen when held out at arms length, or 10 times the width of the Moon as seen in the sky.


For example, for the alignment on the "Night of the Smiley Face Fritz", Venus, Jupiter and the crescent Moon were all together within 3º of each other. On the same night, Mars, Mercury and the Sun were all within 3º of each other (there weren't any X-class flares though).

The "alignment" at the time of the Carrington Event had Mercury, Venus, Mars and Saturn strung out in a line that covered 12º, with Venus 7 º from the Sun. This is pretty marginal as alignments go.

For example, much tighter and closer alignments have not produced any significant solar flares. Like the 17 June 1872 conjunction when Venus, Mars and Mercury were all within 1º of each other and 7º from the Sun, nothing happened, or 22 August 1891, when Mars and Venus were 0.01º from each other and 7º from the Sun, or 19 June 1904 when Mars and Venus were 0.3º from each other and 5º from the Sun.

Or  24 August 1987, when Venus and Mars were lees than 30' (arc seconds) apart, 1º from the Sun, the Moon 3º away and Mercury 4º away, Zilch (solar flare wise).

But these are isolated examples, to get an unbiased picture of what is going on, we need to look at statistically valid samples of flares and alignments. 

Which brings us back to what an alignment is. 

For the purposes of this exercise, for a single planet to be aligned with the Sun, it has to be within 5º of it. For multiple planets, I've allowed that two planets must be within at last 10º of each other and at least one member of the group within 15º of the Sun.

So with those definitions, what does the flare/alignment profile look like.

Table 1. The most powerful X class flares since 1976 and their association with alignments. Alignments found using the events tool in SkyMap. Alignments defined as described above.

-------	-------------------------------	--------
Ranking	Day/Month/Year
-------	-------------------------------	X-Ray Class	Alignment Present?
1	4/11/2003	X28+	No
2	2/04/2001	X20.0	No
2	16/08/1989	X20.0	No
3	28/10/2003	X17.2	Mercury 2 degrees from Sun
4	7/09/2005	X17	Venus and Moon close, but 40 degrees from Sun
5	6/03/1989	X15.0	No
5	11/07/1978	X15.0	Jupiter 25' from Sun
6	15/04/2001	X14.4	No
7	24/04/1984	X13.0	Mercury 3 degrees from Sun
7	19/10/1989	X13.0	No
8	15/12/1982	X12.9	Moon 4 degrees away
9	6/06/1982	X12.0	No
9	1/06/1991	X12.0	No
9	4/06/1991	X12.0	No
9	6/06/1991	X12.0	No
9	11/06/1991	X12.0	No
9	15/06/1991	X12.0	Mercury  3 degrees from Sun
10	17/12/1982	X10.1	Mercury, Venus 2 degrees from each other, 7 degrees from Sun
10	20/05/1984	X10.1	No
11	29/10/2003	X10	Mercury 2 degrees from Sun
11	25/01/1991	X10.0	No
11	9/06/1991	X10.0	No
12	9/07/1982	X 9.8	No
12	29/09/1989	X 9.8	Mars 1 degree from Sun, Mercury and Moon 2 degrees appart 10 degress from Sun
13	22/03/1991	X 9.4	No
13	6/11/1997	X 9.4	No
14	24/05/1990	X 9.3	Moon 8 degrees away
15	5/12/2006	X 9.0	Mars, Mercury, Jupiter within 6 degrees of each other, Jupiter 10 degrees from Sun
15	6/11/1980	X 9.0	No
15	2/11/1992	X 9.0	No

A Carrington Event style alignment on 15 May 2002. No flares occurred at this time (click to embiggen).

As you can see, there were no alignments during the most powerful X-class flare recorded since 1976, and neither was there an alignment during the 1989 flare that blacked out Canada. Mercury comes close to the Sun (in the absence of other planets nearby) during a few flares, but as Mercury comes close to the Sun often that is expected by chance alone.

So far not looking good for alignments and flares.

So lets look at alignments during the 2001-2003 peak of the last solar maximum.

Table 2. Planetary alignments during the last solar Maximum (2001-2003) and their association with X class flares. These are the dates when Venus and the Moon were aligned (minimum separation distance of 5º between Venus and the Moon, and maximum distance of 15º from the Sun). Other planets identified as being within either 5º of Venus or the Moon. Alignments identified using the events tool in SkyMap. Flare list from NASA, a flare occurring in the same month as any alignment was counted as positive.

Date of Alignment	X-Class Flares?	Other Planet?
25 Mar 2001	Yes	No
14 Nov 2001	Yes	No
14 Dec 2001	Yes	No
13 Jan 2002	No	Mercury
12 Feb 2002	No	No
15 May 2002	No	No
04 Nov 2002	No	Mercury
28 Jun 2003	Yes	No
28 Jul 2003	No	Saturn
27 Aug 2003	No	Jupiter
26 Sep 2003	No	Mercury

Again, not looking good for flares and alignments. While there were other occasions when planets were close together they all occur too far away from the Sun (>20º) to be meaningful in the solar flare context. Also, in quiet years alignments go on quite happily, without any flares (I leave this as an exercise for the reader).

Everything we have seen is entirely consistent with chance association with flares and alignments.

The video does give some predictions, but they are very fuzzy "may result in exaggerated solar activity" this could mean anything from mere M class flares to high rating X class flares. Certainly The two X class flares we have had since July (13 July X1.4 and 23 October X1.6), were not predicted. The predicted dates of August 22 and September 21 (and the days either side) are devoid of flare activity greater than C8. October 3 and October 14 (and the days either side) miss out on anything and October 21 has an M class flare.

Hardly an encouraging hit rate, given that since July we have had roughly a C8 or larger flare roughly every 4 days. You could do better by flipping a coin.

Planetary alignments and solar flares? Just say no!

Labels: alignment, Moon, Pseudoscience, Solar flare, Sun