Unistellar Citizen Astronomers are invited to participate in this week’s quest to observe celestial objects in the Leo constellation!
Quick facts about the Leo constellation:
- In Latin, Leo means “lion”
- Leo was one of the earliest identified constellations. There is evidence that Mesopotamia had a similar constellation in 4000 BCE.
- Regulus (also known as Alpha or α Leonis) is the brightest star within Leo.
- Leo is the 12th largest constellation in our sky (out of 88).
- In the Northern Hemisphere, the best time to view Leo is Spring. For the Southern Hemisphere, the best time is Fall.
Stars in Leo
eVscope images captured by Unistellar Citizen Astronomer David Rowe, from Wimborne, United Kingdom
The above eVscope images show stars within Leo:
- Regulus (Alpha or α Leonis): a multiple star system, made of at least four stars. The dominant star is a blue-white subgiant star.
- Denebola (Beta or β Leonis): the second brightest star within Leo and is a blue-white star. Denebola means “the lion’s tail.”
- Algieba (Gamma or γ Leonis): a binary star system. Binary star systems are two stars that orbit each other. The dominant star is a gold-yellow giant star.
- Zosma (Delta or δ Leonis): is a blue-white star, larger and hotter than our Sun
- Adhafera (Zeta or ζ Leonis): a white giant star. It is close in the sky to another star within Leo known as 35 Leonis. Since they are about 174 light years from each other, they form an optical double, a pair of stars that appear close to each other as viewed from Earth, but aren’t related.
- Rasalas (Mu or μ Leonis): a star slightly more massive than our own Sun. In 2014, an exoplanet over 2 times as massive as Jupiter was discovered around it.
Observing Tips:
- We recommend using the Enhanced Vision mode when viewing stars to bring out their colors.
- Depending on the sky quality at your location, you may want to leave the Enhanced Vision mode on for at least a minute.
Deep-Sky Objects in Leo

eVscope image mosaic captured by Unistellar Citizen Astronomer Gary Wingerd, from Utah, USA
The Leo Triplet
The Leo Triplet is a group of three spiral galaxies about 35 million light years away from us:
- Messier 65 (on the bottom left)
- Messier 66 (on the top left)
- the Hamburger Galaxy (on the right), also known as NGC 3628
They are a trio of interacting galaxies, meaning their gravity affects each other so much that it is changing their shape.
Observing Tips:
- Search for “M65,” “M66” or “NGC 3628” in the Explore tab of the Unistellar app.
- Depending on the sky quality at your location, you may want to leave the Enhanced Vision mode on for at least 20 minutes.
- Recommended Bortle Class is 5 or lower.

eVscope image captured by Unistellar Citizen Astronomer Gary Wingerd, from Utah, USA
Messier 105, NGC 3384 & NGC 3389
Messier 105 (M105) is an elliptical galaxy 32 million light years away from us (on the bottom right).
If you use your eVscope to observe M105 you’ll probably notice two other galaxies in your view: NGC 3384 and NGC 3389. The closer galaxy to M105 is NGC 3384, a barred lenticular galaxy (on the top right). Lenticular galaxies are in between elliptical and spiral galaxies. The smallest galaxy seen here is NGC 3389 and is classified as a spiral galaxy (on the left).
Observing Tips:
- Search for “M105,” “NGC 3384” or “NGC 3389” in the Explore tab of the Unistellar app.
- Depending on the sky quality at your location, you may want to leave the Enhanced Vision mode on for at least 20 minutes
- Recommended Bortle Class is 5 or lower.

eVscope image captured by Unistellar Citizen Astronomer David Hein, from Adelaide, Australia
NGC 3521
NGC 3521 is a spiral galaxy 26 million light years away. Much like the Sunflower Galaxy (M63), it is known as a flocculent spiral galaxy, because of the fluffy, patchy, and discontinuous nature of its spiral arms.
Observing Tips:
- Search for “NGC 3521” in the Explore tab of the Unistellar app.
- Depending on the sky quality at your location, you may want to leave the Enhanced Vision mode on for at least 20 minutes
- Recommended Bortle Class is 5 or lower.
We encourage you to share your observations and join the conversation through our Facebook, Instagram and Twitter pages using the hashtag #UnistellarChallenge!
If you’d like to send us your observations by email, send them to community@unistellaroptics.com.
Clear skies! 🔭