Comet in spectacular flare-up

Reports are coming in of a major outburst by a normally faint comet, P/Holmes (17P). It would normally now be expected to be around magnitude 17 but it appears to have undergone a huge eruption. Amazingly, the comet has become a million times brighter, and has reached magnitude 2.5. It is starlike in appearance and so an easy object to see with the unaided eye, distorting the shape of the constellation of Perseus. We don't know how long the brightening will last, but the comet is well positioned to be seen all night from the UK. At midnight tonight, UK time (24/25 October), it will be at RA 03h 53m Dec +50 08' in Perseus. Update: In a special email alert issued by Sky & Telescope magazine, since I wrote the above, senior editor Roger W. Sinnott says that the latest startling outburst may be even stronger than one that occurred 115 years ago, in November 1892, when the comet was first spotted by English amateur Edwin Holmes. He reports that A. Henriquez Santana, at Tenerife, in the Canary Islands, was first to notice the current outburst shortly after local midnight today (Wednesday, 24 October). The comet was then about 8th magnitude, but within minutes Ramon Naves and colleagues in Barcelona, Spain, caught it at magnitude 7.3. By the time it grew dark in Japan, it was visible from the centres of large cities and had reached magnitude 2.8. Sinnott says that cometary expert Gary Kronk expects Comet Holmes to remain bright and grow from a starlike point to several arcminutes across over the next few nights as it makes its way slowly westward across Perseus. Here is a hastily created map showing tonight's position. For swift alerts to such exciting events, you can sign up to the Society for Popular Astronomy's free, if quaintly named, Electronic News Bulletins. Further update: Read the latest on Comet Holmes at the SPA's website. ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA, the UK, Canada and France. They are powered by Amazon so you can buy with confidence.

Deluge of dust from Halley's Comet

The Earth is currently ploughing through a river of dust cast off long ago by Halley's Comet. First impressions indicate that they are putting on an excellent show. The cosmic debris reveals itself as bright meteors, or shooting stars, as particles stream into the Earth's atmosphere from space and vaporize in an instant. This shower is known as the Orionids because the meteors all appear to radiate from the direction of a point near the club being wielded by Orion, the hunter. The shower is long-lasting, with it first meteors becoming visible as early as October 2, and other being seen as late as the first week of November. It is one of two meteor showers left by Halley's Comet. The other is the η Aquarids in late April and May. Maximum of the Orionids occurred yesterday, October 21, when experts at the International Meteor Organization were forecasting zenithal hourly rates (ZHR) of 25 an hour - that being the ideal figure expected if the shower radiant was directly overhead and skies were perfectly clear and dark. In reality, conditions mean that a much lower figure than the ZHR is actually observed by a single observer. However, the Society for Popular Astronomy's hard-working Meteor Section director, Alastair McBeath, is today reporting a much stronger return for the Orionids this year, with double or more the predicted rate. From his observing site in Northumberland, in the north of England, Alastair counted 52 Orionid meteors in the space of three hours on the night of October 20-21. He also saw 31 other non-shower meteors, so it was a productive night. Alastair's quick calculations from this data suggest a "very healthy" ZHR of 50-60 for the Orionids. As Alastair is quick to point out in the SPA's excellent and free Electronic News Bulletins, this data needs to be confirmed by other observations, but the IMO's own website appear to back his own findings. Indeed, their live graph suggests a brief spell where Orionid rates peaked at around 120 meteors an hour. Alastair says that elevated ZHRs were already being reported from at least October 19 and high rates could continue for a couple more nights. The Moon is gibbous and bright and will drown out fainter meteors for much of the night, but if it is clear where you are, it could still be worth wrapping up warm and taking a look. ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA, the UK, Canada and France. They are powered by Amazon so you can buy with confidence.

How to find Venus in daylight

A daylight Venus and the Moon in June The planet Venus is currently shining brilliantly in the pre-dawn sky. This world, the next closest to the Sun after the Earth, is fascinating to view through a small telescope because it shows phases like the Moon. You will not see anything of its surface, however, because Venus is permanently shrouded in cloud. By all accounts that surface is as close a place to hell as can be imagined, which may seem surprising considering its jewel-like beauty. Venus's clouds are highly reflective of sunlight which is why it shines so brightly. It appears as the third brightest object in the heavens after the Sun and Moon. It is so bright, in fact, that you do not need to rise at an unearthly hour to see it - Venus is visible in broad daylight to the unaided eye. This may come as a surprise because we are not used to glancing up and seeing our neighbour planet in a daytime sky. The problem is that it is not obvious when the Sun is drowning out everything else in the sky and so you need to know exactly where to look. It is also difficult for the eyes to focus on the planet when they are just gazing into an indistinct sky-blue canvas. I have followed Venus through the daytime sky on a number of occasions. It has certainly been easier in parts of the world with clear blue skies, such as Provence in the south of France, rather than the UK with its customary milky skies, but even under such conditions it is possible thanks to Venus's brightness. One way to keep Venus in view is to wait for a time when the Moon lies close to it in the sky. A planetarium-style computer program can help here - fire it up and see where Venus lies relative to the horns of the Moon (which will always be a crescent if near the planet). Because of its size, the Moon is a lot easier to spot in daylight, so it can help to find the Moon and then use it to locate Venus when nearby. I last used this technique on June 18, shortly after Venus was actually occulted by, or hidden behind, the Moon from the UK, and the planet was an easy object to spot. The photo above was taken a couple of hours after the occultation ended as the Moon was moving away. One interesting observation made clear in the photo is to note how much brighter Venus is, area for area, than the Moon. Our natural satellite's dark, rocky surface is a much poorer reflector of sunlight than Venus's clouds. We should be grateful for that or we would see little of the sky's fainter inhabitants when the Moon was in the sky! If you are looking for Venus in daylight, then hiding the glare of the Sun behind a building or tree will help. And the obligatory warning to beginners: NEVER sweep for Venus with binoculars in daylight if there is any danger of accidentally pointing them at the Sun! You could be blinded. ©PAUL SUTHERLAND, Skymania.com • Skymania welcomes your comments on our stories! For more space reading, check out the Skymania stores in the USA, the UK, Canada and France. They are powered by Amazon so you can buy with confidence.