Seven Sisters and hidden worlds

As the evenings lengthen, it’s a lovely time to revisit the Pleiades and explore what light and motion reveal about distant stars. This month: a photograph from the gallery, two interactive experiments and a few dates for your stargazing diary.

FROM THE GALLERY

The Pleiades: a small cluster with a big story

The Pleiades (M45) — photograph by Alan Vigner

Around 440 light-years away, the Pleiades form a young star cluster in Taurus. Its brightest members are hot, blue stars. The blue wisps revealed in long exposures are dust scattering their starlight: a reflection nebula.

From the UK or France, look east during November evenings for this compact little group. How many stars can you separate with your eyes alone? Binoculars reveal many more, although the blue nebulosity is far harder to see than a photograph suggests.

Explore the gallery →

TWO EXPERIMENTS TO TRY

How do you weigh a star?

You cannot put a star on a scale. But when it has a companion, their orbital motion gives astronomers a way to measure mass. Move the controls and explore what their dance can tell us.

Try the experiment →

Can you discover a hidden planet?

A planet can disappear in the glare of its star. When it passes in front, it blocks a little starlight and produces a dip in brightness. Explore that signature and try to uncover an unseen world.

Try the experiment →

Your November sky

Around 9 November
New moon brings a useful window for star clusters and other faint targets, away from artificial lights.

Night of 17–18 November
The Leonids reach their peak. Try the hours after midnight, once the Moon has set: a dark sky, a chair and warm clothes are all you need.

24 November
The full Moon is a “supermoon”. Enjoy its rise over a familiar landscape; it still looks like a full Moon, with a fairly subtle change in apparent size.

Dates: Royal Observatory Greenwich →.

Give someone a moment under the stars

Looking for a Christmas gift for someone who loves astronomy? Get in touch to discuss a private online session exploring deep-sky objects with the Seestar S50. Live observing depends on the weather.

Ask about a gift session →

Clear skies,
Alan
Show Me The Sky