Halley’s comet highlighted in Royal Astronomical Society meeting. Since antiquity, comets have been associated with portents and omens. The most famous comet of all is probably comet Halley or Halley’s comet, implicated in King Harold’s defeat by the Saxons in the 1066 Battle of Hastings and depicted in the 230-foot Read more
by AOP Astronomer Gavin Ramsay Today the European Space Agency (ESA) successfully launched its Jupiter Icy Moons Explorer (JUICE) mission from Kourou in French Guiana on an Ariane 5 launcher after it was delayed for a day due to a weather forecast of potential storms. In the planning stage for Read more
Those of us out and about on Spring evenings have been treated to a brilliant beacon of light above the western horizon. This is the planet Venus, our closest solar system neighbour. Venus has been called Earth’s “evil twin”, in that it is almost identical in size, mass and density Read more
At certain times of the year, the Earth passes through streams of dust left behind by comets, leading to a natural fireworks display: a meteor shower. One of the best-known is the August Perseids; at the peak of the shower, one can see about 100 meteors per hour on a Read more
Written by Apostolos Christou As far as astronomers know, the Earth is alone in its annual trek round the Sun – that is, apart from its natural satellite: the Moon. But our current understanding of how the solar system formed suggests it may not have been always so. For instance, Read more
Article by Ed Snowdon Whether you are a researcher gathering data, or a hobbyist taking photos from your back garden, astronomy has always required a certain amount of good luck. Instruments can be uncooperative, data can be lost or damaged, and of course there’s the ever-present threat of bad weather. Read more
Written by Gavin Ramsay A number of Armagh astronomers travelled this week to the University of Warwick in England to take part in the first `in-person’ UK National Astronomy Meeting since 2019. Over 800 people participated either in person or remotely. For many PhD students it was the first big Read more
Written by Gautham Sabhahit Over a century ago, Albert Einstein formulated his general theory of relativity (GR, also called Einstein’s theory of gravitation) describing the motion of objects in space and time under the influence of nearby matter and radiation. The theory formulated ‘gravitational force’ as a geometric property of Read more
Ask any number of astronomers who they believe to be the most influential figures in 20th century astronomy and chances are you will hear the name of Vera Rubin being uttered a few times. Recipient of numerous awards and accolades including the Royal Astronomical Society’s Gold Medal, Vera Rubin (nee Read more
The month of December offers us the most intense meteor shower of the year. These are the Geminids, so-called because they appear to emanate from the constellation of Gemini the Twins. At the peak of the shower, over 120 meteors – two meteors every minute – can be spotted under Read more
Armagh Observatory and Planetarium reports that, if skies are clear on the morning of 19th November 2021, sky-watchers will witness a partial eclipse of the Moon. The eclipse begins at 0720 am Greenwich Mean Time (GMT) when the Moon is only 5 deg above the NW horizon. At that time Read more
Orionids are debris from comet Halley that graced Earth’s skies in 1986 and is expected to return to the vicinity of the Sun in 2061. Orionids tend to be quite fast, hitting the Earth’s atmosphere at 66 km /sec. This is fast enough to cross the Atlantic Ocean in about Read more
by Apostolos Christou During the past week, Earth passed through the core of the Perseid meteor shower. The peak of the shower – when up to 100 Perseids could be observed under clear conditions away from light pollution – occurred between the 11th and 13th of August. Three bright Perseids Read more
When Apollo 15 astronauts David Scott and Jim Irwin touched down near the lunar Appenine mountains in the summer of 1971, they brought along a rover to aid them in their exploits. The use of this Lunar Roving Vehicle – or LRV as it was called – was the first Read more
by Apostolos Christou On the 11th of July 2021, we were informed that Virgin Galactic’s CEO Sir Richard Branson and his fellow passengers onboard VSS Unity reached “the edge of space”. But why “the edge” and not simply “space”, surely space is a well-defined domain so that one either reaches Read more
How many moons can you see with the naked eye? The answer may surprise you.. Of the hundreds of moons orbiting the planets of our solar system, all but four are too faint to see with the naked eye. One of the four is, of course, Earth’s own Moon. The Read more
Armagh Observatory and Planetarium reports that, if skies are clear on the morning of 10th June 2021, sky-watchers will witness a partial eclipse of the Sun. A solar eclipse occurs when the Moon passes between the Earth and the Sun, in effect casting a shadow on our planet. When the Read more
What do a tree, a colander and a piece of cardboard have in common? The answer: they can all be used to observe a solar eclipse! Our Sun – the brightest star in the sky – has been the subject of intense scrutiny ever since human beings began to interrogate Read more
by Apostolos Christou An international team of planetary scientists led by astronomers at AOP have found an asteroid trailing behind Mars with a composition very similar to the Moon’s. The asteroid could be an ancient piece of debris, dating back to the gigantic impacts that formed the Moon and the Read more
by Galin Borisov and Apostolos Christou This September, we had the first opportunity to make astronomical observations while physically present at the telescope since the start of the COVID19 pandemic. Our instrument of choice was the 2-m RCC telescope at Rozhen Observatory on the Rhodope mountains in SW Bulgaria. So here we are at 1700m above sea level with a forecast for good weather and ready for new discoveries! One Read more
When the first astronauts came back from the Moon more than half a century ago, they brought back a scientific treasure trove of soil and rock samples. These were – and still are – intensely scrutinised in laboratories all over the world, allowing scientists to gradually piece together the history Read more
Mars is the only other planet in the solar system apart from the Earth that combines a clear – albeit thin – atmosphere and a solid surface. Therefore, an astronaut standing on the surface may observe and record phenomena on the martian sky, both astronomical and atmospheric. One of these Read more
By Apostolos Christou, Researh Astronomer Every 26 months, the positions of Mars and the Earth align in such a way to allow probes launched from Earth to reach Mars (see how to calculate launch windows here). The next such launch window has just opened, with three separate missions under starter’s Read more
A myth deeply engrained into popular culture is that the Moon is made of green cheese. The Apollo missions showed beyond reasonable doubt that the moon is made of rock and not, sadly, of one of our favourite dairy products. That being said, data brought back from Apollo and the Read more
When Thomas Romney Robinson, director of the Armagh Observatory, invented the cup anemometer in 1846, little did he know that one day his invention would be recording the alien breeze on the surface of another world. Fast forward 130 years: On 20 October 1975, a small capsule detached from the Read more
By Gavin Ramsay, AOP Research Astronomer In previous AstroNotes we have highlighted the Gravitational-wave Optical Transient Observer (GOTO) project of which AOP is a partner. Although its main aim is to detect the optical counterparts of cosmic explosions, it has been used to observe some Comets. Last week GOTO observed Read more
By Simon Jeffery, AOP Research Astronomer In 1930, Dorrit Hoffleit reported that star number #4749 in the Harvard List of variables had faded four times between 1897 and 1929, and identified it as an R Coronae Borealis (RCB) variable. RCB stars are luminous low-mass stars (red giants) with surfaces around Read more
Research Astronomer Dr Apostolos Christou reports on a new model to explain the two “oddball’’ moons of Neptune: Triton, a >2000 km diameter satellite that circles Neptune in the opposite direction that the planet rotates; and 300-km Nereid, the planetary moon with the most elongated orbit in the solar system. Read more
The transition region in the Sun is the atmospheric layer that separates the cooler chromosphere from the hotter corona. Studying the structure and dynamics of the transition region requires greater attention as these provide critical information on the supply of mass and energy from the lower atmosphere to the corona and Read more
By Galin Borisov (not the interstellar comet discoverer) During this tough period of COVID-19 pandemic, most of the astronomical observatories around the world are closed and no observations are carried out. But my Bulgarian colleague, Yanko Nikolov, decided to self-isolate in the mountain and fulfil the observations with the 2m Read more
By Christopher Duffy Studies of the sun, our closest star, have shown that sun spot activity and solar eruptions, also known as solar flares, are strongly correlated – regions of the sun with many sun spots are found to be the typical point of origin for most solar flares. This Read more
Those of you going out late in the day for an evening stroll or just enjoying the spring smells in your garden may have noticed a bright white beacon of light shining high in the west after sunset. This is Venus, the closest planet to the Earth and the brightest Read more
By Professor Gerry Doyle The solar chromosphere is a complex magneto-plasma system that offers the evolution of a variety of plasma dynamics (e.g., jets, mass motions, shocks) as well as magnetic waves. It is separated by the inner corona through the particular discontinuities of mass, density, temperature, characteristic speeds, etc. Read more
By Marc Sarzi, AOP Head of Research In an age dominated by fast-paced but also dispersive and often incorrect communications, we are often exposed to misleading or irrelevant information. Obtaining reliable news and advice is particularly important today as we live through the middle of the COVID-19 pandemic. For this Read more
It’s not every day, or every year for that matter, that we get to see a really bright comet. Many of us, including the author of this article, remember comet Hale-Bopp that adorned Earth’s skies in the first months of 1997. Since then we’ve had several comets bright enough to Read more
By Bill Napier, AOP Visiting Astronomer A comet typically comprises about 50% fine dust embedded in a frozen matrix of water, methane, carbon dioxide and other organic compounds. Approaching the inner planetary system it begins to disintegrate, with fragments splitting off along with dust and gas. The fragments spread around Read more
Just released are first images and videos from the National Science Foundation’s (NSF) Daniel K. Inouye Solar Telescope (DKIST) – revealing unprecedented detail of the Sun’s surface, with experts saying it will enable a new era of solar science and a leap forward in understanding the Sun and its impacts Read more
AOP researchers have used data from a NASA space mission to shed light on one of the most violent phenomena in our solar system – magnetic explosions on the surface of the Sun. Abhishek Srivastava, formerly a research associate at AOP and now a solar scientist at the Indian Institute Read more
Observers in Ireland and Great Britain will have an opportunity, weather permitting, to observe a rare astronomical event on Monday 11th November, when the planet Mercury will transit across the Sun. Transits occur when a planet lies directly between the Earth and the Sun. With suitable observing equipment, Mercury may Read more
The Sun’s corona is maintained at a temperature in excess of a million degrees. The corona lies above the solar photosphere which is maintained at 6000 degrees. These regions are only a few hundred kilometers apart. A major scientific problem in solar physics is how and why is the corona Read more
Those of you who have been on this planet for longer than a few decades may recall the early days of the space age, when rocket launches were far from commonplace and each probe launched promised to do something fundamentally new: the first satellite to orbit the Earth, the first Read more
If you are a professional astronomer working on this island, then all roads lead to Armagh for you this Autumn! AOP and the City of Armagh are proud to be hosting the Irish National Astronomy Meeting or INAM from the 4th to the 6th of September. Held each year and Read more