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Advanced Amateur Astronomy with Slooh


Introduction Since Slooh launched in 2003, with four telescopes at the world-class astronomical site at the Institute of Astrophysics of the Canary Islands, Slooh members have followed a number of astronomical pursuits:

  1. Tracking Near-Earth Asteroids, making astrometric measurements of their positions to submit to the Minor Planet Center (to determine accurate orbits).

  2. Monitoring the morphology of comets including participation in the largest collaboration projects between professional and amateur astronomers.

  3. Supernovae, novae, comet, and asteroid discovery programs.

  4. Art astronomy where members collect the raw astronomical FITS data and process their own color images.

Slooh expanded its telescope network in 2009 when it launched its southern hemisphere observatory at the Pontificia Universidad Católica de Chile facility near Santiago. This not only opened up southern hemisphere skies, with its myriad of deep sky objects, but more importantly, allowed those members tracking asteroids and comets, and those pursuing discovery programs, to access regions of the southern skies poorly served with telescopes. Further expansion of Slooh's observatory network is underway to extend the hours of operations and sky coverage. Slooh's Near-Earth Asteroid Tracking Program ​With widespread global media coverage, Slooh's decade-long campaign to raise awareness of the threat from Near-Earth Asteroids is well known. But why was the campaign started?

On the night of October October 6th, 2008, Slooh Member Tavi Greiner heard about an asteroid that had only been discovered earlier that day. Astronomers had calculated that it would impact Earth! Greiner immediately scheduled Slooh's telescopes at the Institute of Astrophysics of the Canary Islands to capture the fast-moving asteroid “2008 TC3” as it approached Earth. Slooh members watched the live stream in amazement as they identified the primordial space rock whizzing across the skies - and they were among only a handful of people to do so that night. Two hours later, the 80-tonne, 13ft diameter asteroid entered Earth's atmosphere 23-miles above the Nubian Desert in Sudan where it exploded in a massive fireball. It felt like science fiction - and it was obvious from discussions in the Slooh community that members were extremely surprised – and shocked - that an asteroid could impact Earth with so little warning. In the weeks and months that followed, we started to understand that this wasn't a lone instance. We also established that many known asteroids, discovered at high cost by a few professional observatories, became "lost" because no one was tracking or monitoring them after their initial discovery. The entire event inspired Slooh members to begin tracking these Potentially Hazardous Asteroids whenever they swung past the planet. With Slooh’s assistance, a small group of members taught themselves how-to use Slooh’s robotic telescopes to make astrometric measurements (measuring the precise position of the fast-moving asteroids against the fixed background stars). As Slooh began their campaign to raise the awareness of the risk from these rogue space rocks, more and more members were interested in tracking asteroids and comets. The group developed a fully structured training program to teach other members how-to track and monitor these potentially cataclysmic space rocks. Since the Slooh NEA Tracking Program was launched, members have submitted nearly 10,000 measurements to the Minor Planet Center, allowing the asteroids’ orbits to be determined with accuracy – making it far less likely that they will be lost. Their observations have also been published in research with the Max Planck Institute. Alongside the members’ tracking program, Slooh launched a campaign of live broadcasts to raise the awareness of the threat to Earth from NEAs. Live streaming of the NEAs and Potentially Hazardous Asteroids as they made their close approaches to Earth allowed Slooh to reach millions of viewers. Slooh astronomers were joined by guest experts, including astronauts and NASA officials, to explain why the program was so important. Slooh’s coverage of a series of large asteroids making close approaches to Earth only days after they were discovered brought the attention of the media who syndicated many of Slooh’s live broadcasts. In June 2014, Slooh was invited to participate in NASA's Grand Asteroid Challenge, and later signed a Space Act Agreement with NASA to extend the reach of Slooh's asteroid-tracking program. Over ten years later and Slooh members are still dedicated to this valuable pursuit, with a continuous stream of members graduating through the training program.

Slooh Comet Monitoring ​Of all the objects visible through Slooh’s robotic telescopes comets have always been among the most popular. Since 2003 when the telescopes reached “first light”, members have been capturing and monitoring comets as they travel through the inner regions of the solar system. Spurred on by the success of the NEA tracking group, a number of members interested in monitoring comets formed in 2012 – the “Comet Attributes, Track and Search” (C.A.T.S.) group. With telescope coverage of both the northern and southern hemisphere, Slooh members were able to monitor comets when they fell out-of-reach from northern hemisphere amateur and professional observatories. The ability to monitor comet morphology over such long periods of time proved invaluable – and came to the attention of the professional community. Later in 2012, a new sungrazing comet, C/2012 S1 (ISON), was discovered. It would potentially be the most spectacular comet for a decade. Professional astronomers knew they didn’t have the wherewithal to monitor Comet ISON as it approached the Sun – so a NASA-backed program called the Comet ISON Observing Campaign (CIOC) was launched that encouraged and facilitated a massive, global and celestial observing campaign. With large telescopes at the world-class observatory site in the Canary Islands, Slooh members would turn out to be among the most prolific observers with vast amounts of high-quality data collected and made available to the professional community. This valuable data was referenced in several scientific papers with members credited by name for their contributions. Further “Pro-Am” projects were spawned from the CIOC – Slooh members participated in all of them. Many of the project managers of these campaigns are also Slooh members themselves – acknowledging how capable the Slooh telescopes are. The most recent campaign, the “4*P Coma Morphology Campaign”, saw members working with other amateur astronomers and the professional community to track three periodic comets, 41P/Tuttle-Giacobini-Kresak, 45P/Honda-Mrkos-Pajdusakova, and 46P/Wirtanen, as they approached the Sun. Because of the location of Slooh’s observatories, members were able to track each comet over longer periods of time than any other group. Slooh members also worked with the European Space Agency (ESA) and generated the largest set of ground-based data of comet 67P/Churyumov–Gerasimenko – the comet visited by ESA's Rosetta Mission. This long period of continuous monitoring helped calibrate Earth-bound observations of comets with those from the close-up views seen by the Rosetta spacecraft orbiting 67P. Members also worked with the Jet Propulsion Laboratory (JPL) to track comets. Comets continue to be among the most popular objects among the Slooh membership, and 2019 will see a new “Comet Trackers” club form to continue the valuable work of the C.A.T.S. group. Discoveries Made By Slooh Members ​As well as tracking and monitoring asteroids and comets, several members actively search for them. Discovering either type of object is becoming more-and-more difficult for amateurs as the number of large-scale global sky surveys increases. However, these professional surveys have their limits – most notably, few of them can survey low to the horizon. These areas make superb hunting grounds for Slooh members – especially as they can also observe southern hemisphere skies where fewer professional surveys are located. While we wait for “Comet Slooh” to be discovered, Slooh members have been responsible for capturing a number of “recovery” observations – being the first to capture a returning periodic comet. Long-time comet monitoring member Bernd Lütkenhöner was the first to capture the return of the periodic comet 104P/Kowal on January 3rd 2016. His achievement being marked with the publication of Minor Planet Electronic Circular "MPEC 2016-B13: Comet 104P/Kowal". Bernd commented: "Besides this recovery, I have about 160 confirmations of comets and NEOs, but I stopped keeping a list with these confirmations, but do archive copies of the MPECs." Comets and asteroids are not the only objects tenacious Slooh members hunt. A number search for novae and supernovae – huge stellar explosions. Members have also contributed to professional studies of the cataclysmic events – at a crucial stage. It is extremely important to capture supernova in their early stages, and because Slooh members have immediate access to telescopes, they are also able to make the first “confirmation” observations. They then continue to monitor the progression of the supernova’s brightness that helps determine and understand the physical processes at play. Slooh was cited in a paper about the supernova discovery SN 2007rt alongside JPL and the Max Planck Institute. Slooh Observers and Astro Artists ​Members don’t just pursue scientific projects with Slooh’s robotic telescopes. Many take advantage of Slooh’s patented real-time color processing to build image collections of every type of celestial object in the night sky (as well as the Sun using Slooh’s specialist H-Alpha solar telescopes). These members are like so many amateur astronomers who derive pleasure from exploring the wonders of the night-sky – but without the high cost of purchasing equipment, the steep learning curve required to use the equipment well, and without the poor weather and light pollution that affects so many locations. Some members concentrate on specific object types, others on monitoring changing planetary features across an apparition, and the most tenacious enter long-term projects to capture all the objects in certain astronomical catalogs, such as the Messier and NGC catalogs – the latter containing 7,840 objects! Members share their best images using the Observations feature where they can add their perspective on the image and what makes the moment special or add inciteful comments or information. The best of these observations appear throughout the site as “Featured Observations”. Many members process their own astro art images. These members are among the most active in the Slooh community, sharing techniques and results from their efforts. They collect the raw FITS data generated by the sophisticated and highly sensitive CCD cameras attached to each of Slooh’s telescopes. They combine several sets of FITS data to increase the signal-to-noise ratio, increasing image quality and the detail visible. They also apply their own personal aesthetic preference to the processing that makes each and every resulting image unique to and personal to them. Member Peter Ilas used the Canary Two Wide-Field telescope to win 2nd place in an astrophotography contest run by the largest European astronomy magazine Kozmos in 2015 for his enormous mosaic image, showcasing the Lagoon and Trifid nebulae in Sagitarrius. The following year saw Peter's glorious image of Mechain's Galaxy (M106) placed 9th out of 4500 entries in the "Robotic Scope" category of the most prestigious annual astrophotography content, the Insight Astronomy Photographer of the Year.

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