The Bearscove star party intensity scale

Astronomy clubs often hold star parties, but seasoned attendees and newcomers alike have varied expectations for such events. Jon Bearscove says that’s no wonder. He identified five different types of star party during a talk at October’s meeting of the Seattle Astronomical Society, and also suggested a common rating system so those planning to attend a star party will know what to expect.

Public astronomical observing goes back at least to Great Britain’s King George III, whom Bearscove, founder of the Galileo Astronomy Unclub, described as “a star party guy.” The definition of star party is simple: A gathering of amateur astronomers for the purpose of observing the sky. But star parties can come in a lot of different formats.

Bearscove is something of a star-party commando and knows whereof he speaks. Here are his five types:

  1. Outreach
  2. Observing
  3. Mixed
  4. Publicity
  5. Literal

Outreach is a common type of star party. Most astronomy clubs hold regular events to share members’ love of the night sky with others, and this is a primary mission for many. Clubs may set up a star party in a public park or even a supermarket parking lot and invite anyone who happens by to take a look through their telescopes. Outreach star parties also may be given for school groups, scout troops, or specific communities. Outreach events are highly social and are all about sharing.

Observing star parties are on the opposite end of the spectrum. These are more serious affairs for the hardcore, experienced amateur who is doing research, study, or photography. They are often held at remote locations with much darker skies. While a number of amateur astronomers may be in the same place at the same time, nobody wants to be disturbed.

Obama scope

President Obama’s White House Astronomy Night from 2009 qualifies as a Publicity Star Party. Jon Bearscove says you can’t do much real observing with TV lights on in one of the most light-polluted cities in the U.S. Photo: White House.

Mixed star parties are a blending of the outreach and observing types. The annual Table Mountain Star Party is an example. It’s a highly social event at which people check out everyone else’s cool astronomy gear, but there are some serious observers who attend as well. Usually those who want to be left alone can make it known. Respect those who are doing serious work; bump into someone’s telescope and you might foul up a six-hour photographic exposure.

Publicity is a new category of star party on Bearscove’s list. He describes it as an event with “no purpose” and came up with the notion when he saw photos of an Astronomy Night event held at the White House in 2009.

“If there are bright lights, media coverage, and the Secret Service, it’s a different kind of star party,” he quipped.

Literal star parties are, well, exactly that.

“Star means shiny thing in the sky; party means light, music, booze,” Bearscove said as he explained the category. His example: he once traveled to Japan for the annual Tainai Star Party, often described as the biggest in the world. Bearscove described it as more of a rock concert, with bands, bright lights, vendors, 20,000 people, and “zero observing.”

Bearscove scale

Bearscove, the shadowy figure at the bottom of the frame, explained his Star Party Intensity Scale at October’s meeting of the Seattle Astronomical Society. Photo: Greg Scheiderer.

Bearscove suggests a shorthand way of referring to star parties, inspired by the hurricane intensity scale. His three-step scale loosely corresponds to the observing, mixed, and outreach types of star parties. On the Bearscove Scale a “Category 1” star party would feature extensive observing, “Category 2” would have moderate intensity, and “Category 3” would be the lowest intensity, focused on outreach.

“I think it would be neat if there could be a standard scale,” Bearscove said. “You might have people more interested in a category 2 or a category 1. Everyone’s different.”

His advice for navigating those differences: “Match star parties to your taste,” he suggested. “I like outreach a lot but I also like hard-core observing.” He crosses categories.

It will be interesting to see if the Bearscove scale catches on! Check our calendar, or visit the website of an astronomy club from our list at right, to find the date for the next star party near you.