The United Kingdom is a terrible place to use a telescope, at least if you consider the weather. There might be one clear night a week, or worse. So it probably takes a certain amount of bravery for somebody like John McKeon to invest in a telescope and use it to look at the planets in between dodging clouds and rainstorms and snow.

Yet, McKeon—by all accounts an amateur telescope enthusiast—spotted something to spark the interest of a professional. A video on March 17, taken using only an 11-inch telescope, shows a flash of something impacting Jupiter. What's more is he only thought to check the data after yet another amateur, Gerrit Kernbauer, posted a similar find on Facebook.

"I didn't know for 10 days after I had recorded video that I had discovered it," said McKeon, who originally took the footage to track the double shadow of moons Ganymede and Io moving across the planet. But after he saw the post, he immediately went through the 207 videos he took that night.

"In the second-last video, there was the impact," McKeon said. He posted his YouTube video on Reddit under a post titled, "I most likely caught an impact on Jupiter on March 17." Two months later, the video has close to four million views.

No longer partying like 1994

Planets in the outer solar system beckon to astronomers, but there's only so much telescope time available. A typical telescope swings between different types of observations such as looking at asteroids, peering at nebulas and star clusters in the outer reaches of the galaxy, and doing planetary observations. Sudden events in astronomy can also take over telescope time, such as when Comet Siding Spring slipped past Mars in 2013.

Astronomers are hungry for regular observations of planets to provide insights on their weather, their magnetic fields, and other natural processes. But with limited telescope time available, their views of the planets only come in snatches. This makes it hard to predict how auroras behave on Saturn or how the bands shift on Jupiter.

The importance of these observations is driven home when, for example, a small body hits Jupiter. Amateurs are usually the ones who spot them, especially because amateur astronomy technology is far ahead of where it was in 1994.

H. Hammel/MIT/NASA/The LIFE Picture Collection/Getty Images

Time Life Pictures/JPL/NASA/The LIFE Picture Collection/Getty Images

Alan Levenson/The LIFE Images Collection/Getty Images

Consider the multi-piece remains of Shoemaker-Levy 9 slamming into Jupiter back in that year. The comet was spotted months ahead of the impact, allowing observatories such as the Hubble Space Telescope and the Galileo spacecraft (then on the way to Jupiter) to watch the light show. (The gallery above showcases some of the image quality humanity could capture at the time.)

Back then, most of us used dial-up to access the Internet. YouTube, Reddit, and Facebook—all social media tools McKeon used to spread the word—weren't created until about a decade in the future. And the powers of cheap digital cameras and software that we take for granted today were only accessible then to people with deep pockets and a lot of programming patience.

As such, amateurs mainly watched the impact. The scientists published their observations. Slowly, however, the balance is starting to shift. There's only so much telescope time available on Hubble, which splits its work between planets and deep-space objects based on scientific proposals. An amateur like McKeon, however, can go out night after clear night and look at the same thing.

Today, professionals say amateur work is essential to help us understand how giant planets behave and how often they're hit by something. Amateurs were the ones who discovered Jupiter being smacked at least five times in recent years. And amateurs were called upon to help NASA and others figure out what to observe first when the Juno spacecraft arrived at the king of planets this summer.

The public's camera

After Shoemaker-Levy 9, some astronomers thought that would be the last planetary hit in our lifetimes. Then in July 2009, Australia's Anthony Wesley saw a burn mark left behind from something big hitting Jupiter's atmosphere.

A floodgate of discoveries followed: hits on June 3, 2010 (seen by Wesley and Christopher Go), August 10, 2010 (seen by Kazuo Aoki and Masayuki Tachikawa), and September 10, 2012 (seen by George Hall and Dan Petersen). Most of these were also caught on camera.

Tips to get involved Location: A place with as dark a sky as possible. For most amateurs, it ends up being their own backyard. If you have a reliable car, it may be worth it to drive to a local park or, if you have the time for it, a darker area somewhat outside of the city lights. : A place with as dark a sky as possible. For most amateurs, it ends up being their own backyard. If you have a reliable car, it may be worth it to drive to a local park or, if you have the time for it, a darker area somewhat outside of the city lights. Telescope: Most amateurs recommend an eight-inch telescope to see fine features on planets. Schmidt-Cassegrains are some of the most popular types available in that class, but reflectors and refractors are other possibilities. Instead of buying a telescope based on a website recommendation, go to your local astronomy club and try out the hardware first before committing. Camera: If you're interested in recording pictures or videos, you will need a camera with adjustable shutter settings and the ability to connect to a computer. Again, amateurs have different preferred cameras for observing, so try out a few models before making the purchase. Computer: A computer with hundreds of gigabytes of hard drive space is a must, as well as fast enough processing speed to run software such as Photoshop (to adjust the photos) or digital stacking software (to put multiple photos together into a video). Many laptops can do it these days, but some amateurs prefer the power of a desktop. Check the hardware requirements for your preferred software and try to buy something a little faster than the minimum. Community: Get involved with your local astronomy club. Popular online sites where amateur astronomers congregate include Cloudy Skies, Reddit's Astronomy group, and Facebook's Astronomy Planetary Imaging. Links are also shared on sites such as YouTube and Twitter.

Glenn Orton, a Jet Propulsion Laboratory planetary scientist, has often served as the professional point of contact for amateur observations of these strikes. When a big event occurs, several amateurs told Ars, he is active on social media asking for recordings and other data that could help. He has also been heavily promoting JunoCam and asking experienced Jupiter observers where it should look first.

JunoCam is billed as an unprecedented way for the public to get involved. Dubbed the "public's camera," this imager will allow amateur astronomers to choose targets and also share the images. Amateurs are now submitting pictures from their own telescopes for the community to decide which ones to observe first.

“The 2009 Wesley impact is the most memorable of these impacts for me because he had contacted me, along with other professionals and amateurs,” Orton told Ars via an e-mail as he was traveling. “I happened to be scheduled on the NASA Infrared Telescope Facility to observe Jupiter within 20 hours of his detection, and found two more pieces of evidence ('smoking guns,' as it were) to verify that this was an impact and not one of the zillions of spots and dots on the planet,” Orton added.

The actions of amateurs normally are only covered in the media when a big strike or discovery happens, but Orton said the thousands of hours of data he has received show other points about the gas giant's evolution. This “time-continuum of observations" have shown things such as bands of clouds changing in shape or color over time.

An example of this, he added, was “the discovery of powerful upwelling plumes that have suddenly appeared when very compact regions of Jupiter’s atmosphere have become unstable.” It occurred most recently in 2010, when a usually dark-colored band south of the equator turned pale, sprouted plumes, and gradually became dark again. This event is now being cataloged for a future paper Orton and his colleagues are working on.

Price to play

Observing planets is not a skill closed off to the rich or experienced. Meaningful observations can be made with something as modest as an eight-inch telescope. Prices for these can range from a few hundred to a few thousand dollars, depending on how fancy you want to get.

While McKeon has been observing seriously for only about three years, some amateurs have moonlighting careers that stretch across decades. Damian Peach is one of the most well-known of this group. With about 20 years of “serious” observing experience, his pictures regularly make their way from his website to news sites and from social media to amateur astronomy bulletin boards around the world.

Peach says the entry point for observing is not too astronomical, so to speak, for an interested amateur. Again, it depends on how much you want to spend. Telescopes come with a myriad of lenses and filters. Cameras also have a range of price points and lenses, making it difficult to come up with firm numbers. But anyone with perhaps a few thousand dollars to spend should be able to participate.

Still, the best hardware won't help unless you get some feedback on how to use it properly. Astronomy communities are devoted to sharing data, no matter the experience level of the observer, he said. Popular sites include Cloudy Nights, Facebook's Astronomy Planetary Imaging, and numerous groups on social media and Reddit. What's more, professional astronomers are often on these sites as well, allowing both groups to discuss and exchange observations.

“There's been such a huge amount of interest in amateur work,” Peach said. “We've been well-aware for many years that the best amateur work is of extremely high quality today, and it's very valuable with regard to seeing what's going on on Jupiter.”

For amateurs just getting started, Peach recommends looking up the local astronomy club. Usually these are filled with folks sporting telescopes, lenses, and all the gear a beginner could look for. It allows a chance for a newcomer to try out equipment before committing to buying. (In fact, most astronomy books recommend buying a set of binoculars and using those for at least a few months to learn your way around the sky.)

What's more, these groups often coordinate observations when a big event is happening, such as the Mercury transit that took place a few weeks ago. Some of the bigger groups have websites full of tips for observing. One example is the British Astronomical Association's website, for which Peach is the assistant director of the Jupiter section. It includes recent pictures from members and examples of science that include amateur contributions.

Peach said more people are always welcome in the community, because it adds eyes to the sky. Many an amateur night is ruined by cloudy or rainy weather, especially in the United Kingdom (where he is based). But with a network of astronomers available, it increases the chance of seeing something special on another planet.

“I think (amateurs) are one of the major factors in discovering these impact events,” Peach said. “Now we have so many more people observing regularly. Before, things like this would have otherwise gone unseen.”

From images to useful work

Marc Delcroix, a France-based amateur astronomer himself, is also using the power of an amateur network. In his case, the initiative is gathering data on how often Jupiter impacts occur. For three years, Delcroix has been asking amateurs to send in their data for Jupiter observations. He has now received more than 53,000 videos that total approximately 56 full days of video.

One of those videos was McKeon's showing an impact, while the rest of the amateurs did not have any impacts recorded. He presented his research at the Europlanet 2020 Research Infrastructure international workshop in France earlier in May.

"Amateurs give a major contribution to the study of minor bodies in the vicinity of Jupiter," Delcroix told Ars. He went on to say the community needs to do even more to improve his statistical analysis. One method is by using automated software to go through the videos; Delcroix is working with amateur teams to get this done, but other projects may be available as well.

The other approach is to react quickly. It's very possible that a major impact event could be missed because amateurs don't necessarily have the resources to go through video archives, which is where Delcroix hopes his software fills in the gap.

While not every amateur takes videos of objects, a way to simulate those videos is to “stack” several images and run them one after the other as a time sequence. There is software available to do that, such as RegiStax (a program that was last updated about five years ago) and AutoStakkert. Amateurs also sharpen the images through tools such as Photoshop, allowing subtle features (blurred by Earth's atmosphere) to come through.

"There's almost an art to doing these things," said amateur Fred Locklear, a regular astronomy photographer and past Ars Technica contributor. "If you sharpen too much, you will bring up too much noise. Sometimes you can't use the same sharpening settings on videos."

Despite the small amount of software requirements and editing know-how, amateur observing remains by and large an accessible hobby for everyone. Again, even if you don't have thousands to shell out for a higher-powered system, it's possible to look at the planets with less than $100 and a modest set of binoculars. But for a bit more of an investment in time and potentially money, there are those observers that enjoy contributing to science.

While Juno will only last a couple of years due to Jupiter's intense magnetic environment, it will serve as a first example of amateurs getting to ride all the way to an outer planet and make suggestions about where to look. And perhaps uniquely, Juno will look at features that amateurs can spot at home. It all means now is the perfect time to get involved if you have a telescope, some time, and a love for looking at Jupiter.

Elizabeth Howell is a space journalist based in Ottawa, Canada. She once pretended to be a Mars astronaut in Utah for two weeks. Besides Ars Technica, her work has appeared in Space.com, Discovery News, NASA Astrobiology Magazine, Motherboard, Scientific American and many other publications.

Correction: the original story mistakenly stated that a comet hit Mars, rather than passing close to it.

Listing image by Ian Hitchcock/Getty Images