The evolution of a seven day week coalesced from several different societies and time periods. The primary Western evolution comes from the connection of the five ancient planets (Mercury, Venus, Mars, Jupiter and Saturn) and the Sun & Moon. This was later adopted, like so many things, and transformed into the Christian biblical creation story, with Sunday beginning the week.
What are Planetary Days?
The phrase 'planetary days' refers to the idea that a planet has rulership or influence over a certain day of the week. Planetary days are an ancient reference and existed before the discovery of Uranus, Neptune, or Pluto, and correspond not only with the names of each day (sometimes more recognizable in the Latin form) but are also said to rule the energies of each day. While we generally think of a day beginning at 12:01 AM and ending at midnight, planetary days, like most cycles in Western astrology, are more tied to the cycle of the Sun and Earth, rather than your digital clock. A planetary day begins at sunrise for the given location, and ends at sunrise the following day, when the new planet takes over. Here's a look at what planet is said to rule the day and a suggestion of how to best use the energies of that day at work, home, and play.
Monday: Moon Day
The Moon rules Monday (in Latin: Lunae). This is not a fabulous day to go back to the office, unfortunately! On Mondays (Moon-days), try to start off the day gently, giving yourself time to catch up, so you don't find that you've gone on your merry way trying to get things done and then gotten blindsided by an emotional outburst. When you don't make space for this in your consciousness, it's possible you'll find yourself much more reactive in general to things. It's sort of a 'getting adjusted' kind of day. One thing that may be beneficial on these days is to keep it close to home with a focus on domestic tasks (the moon rules over domesticity and home life). What sorts of tasks you might like to do will depend on your moon especially. If your moon is in Virgo, for instance, the simple act of cleaning and getting things in order (with no 'get it all done' pressure) may make you feel better and calmer. In Cancer, you may need some emotional downtime to warm up to the day and stretch out of your shell. Poetry and music, not memos and telephones, are a good start to your day. In Gemini, you may need to shake your routine up or get your brain cells hopping with some interesting data before you can focus on the tasks of the day.
Tuesday: Mars Day
Mars rules Tuesday (in Latin: Martis). As Ms. Budapest points out in her book The Goddess in the Office, Tuesday is when it seems like the real work week begins! You've gotten through the catch up fog and the chatting about your weekends and now you're ready to get going. Whatever was bubbling in your emotional subconscious on Monday is now coming to the surface and ready to be acted on (Mars likes action!) It might be easier to be in high gear that day and get a lot done rapidly on Tuesdays, so if you've got a big to do list in a certain week, Tuesday is a good day to plan on a lot of it. Tuesdays can be good workout days as well, since Mars has a natural connection to our physical health and wants to help you build strength and raise your power and energy. Watch out for conflict on these days, whether it's in traffic, between you and a co-workers or spouse, or situations caused by just general angstyness and impatience. While Wednesday may be the characteristic day for higher traffic, rude or impatient drivers are more likely on Tuesdays. Be especially diligent about not being careless, in all circumstances. Since Mars focuses on action, it doesn't always like to look before it acts.
Wednesday: Mercury Day
Mercury rules Wednesday (in Latin: Mercurii). Mercury rules all kinds of forms of communication. In some ways, this day can feel the busiest and if you have a high amount of Mercurial energy in your chart, you might enjoy these days most. Take care of any kind of administrative tasks on this day, paperwork, financial statements and balancing the checkbook, making phone calls, sending emails and inquiries, etc. Mercury can also be a good day to run errands of an administrative nature (like going to the post office or the bank, for instance). Also, get organized! If your desk, your bag, your car is a mess, it feels good to get it in order today.
Mercury loves data, so it's especially in charge of all things communication (including the objects we use to communicate and move information: phones, faxes, computers, appointment books even cars). This is a good day to plan your office meetings and your out of office meetups. If you are in classes as a teacher or student, Wednesdays may be particularly busy days, but it often goes smoothly. If you've got an important event or task in front of you, this is a good day to brainstorm. Raising the mental energy is the key here, so anything that helps you think more clearly or get that brain humming is what Mercury loves. Distractions may be more easily succumbed to on this day, since Mercury always likes to feed its curiosity and keep moving and devouring input anywhere it finds it. Yet, if something really catches your attention, it can sweep you up for hours (depending on your personality). Times really does fly on this day (Mercury and his winged feet!) and you can get swept up in a task just as easily as you can in a tangent, a side project that was supposed to be a quick deviation. So be careful about where you focus your attention.
This is always a good day to focus on input as well, not just output. If you are a reader, or a net surfer, or a computer game player, this is a day where that kind of thing can be especially rewarding (but see earlier paragraph about distractions!)
Thursday: Jupiter Day
Jupiter rules Thursday (in Latin: Jovis). Thursdays are a great day to start daydreaming about the weekend and all the possibilities. These days seem to be pretty busy too, and you may often find that many problems come to light, sometimes surprisingly, on this day, especially at work. I have a couple of theories for this: one, issues get blown out of proportion on this day more easily and/or two, people are trying to clean up their desk and issues for the weekend to come. I also find this not a great day for driving. Everyone seems to have their head in the clouds and not on the road! While it may be busy, it's also a good day to have a bit of fun. Make some plans for the weekend. Relax in the evening, maybe have some take out - you're 'over the hump' for the week.
Friday: Venus Day
Venus rules Friday (in Latin: Veneris). "Friday I'm in love," says Robert Smith from the Cure. Indeed! Friday is (or should be) the original "date night." Even at work, Friday is the day we sometimes get the least amount done because we're socializing too much. Spontaneous conversations about weekend plans seem to happen all over the place. This is a great day to indulge yourself in beauty and the arts. Going to a play or an art opening, dinner at a restaurant where a relaxing and beautiful atmosphere is prominent (for the food and the scenery), even a movie - these are all good activities for promoting social activity, something Venus loves, and calming down (unwinding), something Venus also loves. It's also a great day to exercise your creativity.
Saturday: Saturn's Day
Saturn rules Saturday (in Latin: Saturni). This is typically the first day the whole family has off at the same time, and it's time to get everything done that you couldn't get done during the week. How many families have Saturday morning chores? Laundry day? Scrub the bathroom day? Yes, yes, yes. I really recommend a day of getting projects done on this day, Saturn being the 'taskmaster' of the zodiac. This is a less of a quickie errands day and more of a major projects day - a day to do the stuff that is difficult or time consuming. Because Saturn likes results, you may feel better if you get more done earlier in the day and can see some goals accomplished early on.
Sunday: Sun's Day
The Sun rules Sunday (in Latin: Solis). A classic relaxation day. Even God took a break! Sundays are a great sleep in day, at least in the morning, but the Sun's rulership of this day encourages you to get out and enjoy your day. Take a hike, walk your dog, find a comfy chair in the bookstore, get together with friends and family for a late brunch - that's all good stuff. This is a good day to 'shine' and it's a reinforcement of life force energy, so do things that make you feel alive! Your sun sign is a good prescription for what to do to revitalize your energy. Like Venus-ruled Fridays, it's also a good day for creativity, because you put some of you into whatever you create.