Nevermind: Astronomer sends, retracts alert; he accidentally rediscovered Mars

Dr. Peter Dunsby, professor of gravitation and cosmology at the University of Cape Town in South Africa, inadvertently made a name for himself last week.

While reviewing results of an automated astrophotography session with an 80mm refracting telescope from early that morning, Professor Dunsby noted a "very bright optical transient near the Trifid and Lagoon Nebulae." The object wasn't in images of this area captured a few weeks before. He reported it to the Astronomers Telegram, an email service which shares news of gamma or X-ray bursts, supernovae and other transient objects which appear in the sky for some time and then disappear. The message encouraged further observation "to establish the nature of this very bright optical transient."

The "now you see me, now you don't" nature of transient objects makes this kind of instant sharing of information essential. Astronomers worldwide work together to not only validate (like any other science) but also to pick up observations where colleagues have left off as the target sinks below the horizon or the rising sun ends that night’s observations.

Before reaching out to fellow astronomers, Dunsby did check the Digital Sky Survey, a set of photographs of the entire sky used in planning observing sessions with the Hubble Space Telescope among other uses. But all-sky surveys catalog stars and deep sky objects which change position over millennia, rather than days.

Dunsby's discovery wasn’t a new one. It turns out Object ATel 11448 was Mars, with an observational history which predates the written word.

The professor has received a good ribbing in the days that followed on the internet and in the international media. To his credit, he has taken it in stride telling Newsweek, “The world needs to smile more, so that’s something good that has come out of this episode.” He even found humor in the very formal-looking certificate sent by the Astronomers Telegram editors naming him “Discoverer of Mars, March 20, 2018.”

Dunsby later tweeted a lesson for us all: “Check, Check, Triple Check and then Check some more”.

You can discover Mars for yourself when it rises low in the southeast around 3 a.m. this week. Since Professor Dunsby's observations last week, Mars has wandered to the left, out of those nebulae, to a position above the lid of the "teapot" formed in Sagittarius.