Skywatcher's Guide: June and July 2019
- Stars and Constellations
- Solar System
- Calendar of Night Sky Events
- Deep Sky
- Frequently Asked Questions
Stars and Constellations
In June, the spring sky is now prominent overhead, along with the familiar Big Dipper. The Big Dipper is high in the north, and the two stars at the end of the bowl can be used to find Polaris, our north star. Also, the handle can be used to "arc to Arcturus", a bright star in the constellation Boötes. Then Hercules is just below towards the east. Next, Leo the lion is very high in the west, with the constellation Virgo nearby to the south. A few winter constellations are still visible, now vert low in the west. Castor and Pollux, the heads of Gemini the twins, are the most prominent, to the west-northwest. The summer sky is now just starting to come up at the beginning of the night. The bright star Vega in the constellation Lyra the harp is towards the east-northeast. In the southeast we have the constellation Scorpius the scorpion, with the bright star Antares. Further to the south we can also see the constellations of Centaurus and Lupus the wolf right along the horizon.
In July, the last of the winter constellations are now gone, and the spring constellations are beginning to head to the west. The summer constellations are now mostly up in the east. We can easily see all three stars in the Summer Triangle, Vega being the highest in the east-northeast, Deneb a little lower to the northeast, and Altair to the east. To the southeast we can see the Teapot of Sagittarius near the tail of Scorpius. Also, to the north-northeast we can see the W of Cassiopeia the queen.
Interesting Stars Visible in June and July (during observatory hours)
|Name / Designation||Apparent Magnitude
(lower = brighter)
|Regulus||1.36||77||means "Little King"|
|Alpheratz or Sirrah||2.07||97|
|Albireo||3.2 / 5.8 & 5.1||390 / 380||possibly a triple star system|
|Eta Cassiopeiae||3.5 / 7.4||19||480 yr orbit|
Mercury will be visible in the west after sunset throughout June and the beginning of July, but by mid July, it will be passing between us and the sun.
Venus continues getting lower and lower in the east before sunrise.
Mars continues getting lower and lower in the west after sunset.
Jupiter reaches opposition in early June, and will get higher and higher in the east each night.
Saturn is rising earlier each night, and by early July will be visible right after sunset.
Note: The GRS is visible on the disk of Jupiter for 50 minutes before and after meridian transit time.
|Date||Meridian Transit Time|
|06/07/19||Peak of Daytime Arietids meteor shower.|
|06/09/19||First Quarter Moon.|
|06/10/19||Jupiter at opposition. — Best time to see our biggest planet.|
|06/18/19||Appulse of Mercury and Mars. — Separated by only 0.2°.|
|06/21/19||Earth at northern solstice. — Beginning of our Summer.|
|06/23/19||Mercury at greatest eastern elongation. — Visible in the evening after sunset.|
|06/25/19||Last Quarter Moon.|
|07/04/19||Earth at aphelion. — Our farthest distance from the Sun.|
|07/05/19||Appulse of Mercury and Mars. — Separated by 3.8°.|
|07/09/19||First Quarter Moon.|
|07/09/19||Saturn at opposition. — Best time to see this ringed planet.|
|07/14/19||Pluto at opposition. — Best time to look for this dwarf planet.|
|07/21/19||Mercury at inferior conjunction. — Between us and the Sun.|
|07/24/19||Last Quarter Moon.|
|07/24/19||Appulse of Mercury and Venus. — Separated by 5.6°.|
There are several open star clusters we can see this time of year. First, Coma Berenices (Bernice's Hair) is high in the west near the tail of Leo. Next, there is the Ptolemy cluster (M7) and the Butterfly (M6) in the southeast near the tail of Scorpius. Also nearby is the Wild Duck (M11) in the constellation of Scutum.
Now that the Milky Way is coming up, there are several globular clusters we can see. M3 is high in the west, in the constellation Boötes. Nearby, the famous Hercules Globular (M13) is high in the east. We also have M5 high in the south in the constellation of Serpens. Finally, for those with a clear horizon, the amazing Omega Centauri (C80) is visible low to the south.
For nebulae, we can see the Swan (M17), the Lagoon (M8), and the Trifid (M20) to the southeast in the constellation Sagittarius. The Eagle (M16) is nearby in the constellation of Serpens. The North America nebula is also in the northeast in Cygnus. For planetary nebulae, we have the Owl (M97) in Ursa Major high in the northwest. We also have the Dumbbell (M27) in the west-northwest in the constellation of Vulpecula and the Ring (M57) nearby in Lyra.
And now the galaxies: In Ursa Major to the northwest we have Bode's Galaxy (M81) and the Cigar Galaxy (M82), close enough to be seen together in a low-power telescope. Nearby in the constellation Canes Venatici we have the Whirlpool (M51), which is a pair of colliding galaxies. The Pinwheel Galaxy (M101) is also nearby near the handle of the Big Dipper. Then the Southern Pinwheel (M83) is to the southwest in the constellation Hydra. The Sombrero Galaxy (M104) is nearby in the constellation Virgo.
Interesting Deep Sky Objects to Observe during June and July (during observatory hours)
|Designation||Name||Apparent Magnitude||Apparent Size||Distance
|Messier 31||Andromeda Galaxy||3.4||3° x 1°||2,900,000||spiral galaxy|
|Messier 44||Beehive Cluster||3.7||95'||577||open cluster|
|Messier 3||(in Canes Venatici)||6.2||18'||34,000||globular cluster|
|Messier 27||Dumbbell Nebula||7.4||8' × 6'||1,250||planetary nebula|
|NGC 7009||Saturn Nebula||8||36"||2,400||planetary nebula|
|Messier 81||Bode's Galaxy||8.5||21'||12,000,000||spiral galaxy|
|NGC 3242||Ghost of Jupiter||8.6||25"||1,400||planetary nebula|
|Messier 57||Ring Nebula||8.8||1'||2,300||planetary nebula|
|Messier 82||Cigar Galaxy||9.5||14'||12,000,000||galaxy|
Can we see the flag on the moon?
Well, it depends how you are looking. If you are looking through a telescope from here on the Earth, then unfortunately no. To get that kind of resolution, you would need a telescope at least 200 m in diameter. (Our biggest telescopes today are only about 10 m.) And even with a telescope that big, you would have to get around the effects of atmospheric turbulence. However, that is not my final answer...
Besides a flag (actually there are six flags from the six Apollo landings), there are about 200 tons of manmade material left on the moon. These include not only the Apollo missions, but also several robotic missions that are still there as well. But in addition to the material we have left on the surface, we have satellites in orbit around the moon which are able to image the surface with much better resolution than we can here on the Earth. These satellites have imaged the various landing sites and are able to see the objects we left behind, including the flags!
Now if you really want evidence of the lunar landings that you can see from the earth, there is a way. Some of the Apollo missions as well as some Soviet robotic missions left retroreflectors on the moon. Using powerful lasers, we can send a signal to the moon and wait for it to bounce back (about 2.5 seconds round trip). Since the first retroreflector was placed in 1969, scientists have been using these to measure the distance to the moon down to millimeter accuracy, and have shown us that the Moon is receding away from the Earth at a rate of 1.5 inches per year. They have also allowed us to measure tidal forces on the moon from here on the Earth and given us additional proof of the validity of Einstein's general relativity.
If you have any questions you'd like me to answer in the next issue of SWG, please let me know. I'm also happy to take suggestions or comments, and also pictures if you'd like to send them. Happy viewing!
- Cornelius, Geoffrey. The Starlore Handbook: an Essential Guide to the Night Sky. San Francisco, CA: Chronicle, 1997. Print.
- Ottewell, Guy. Astronomical Calendar 2012. Raynham, Mass: Universal Workshop, 2011. Print.
- Ottewell, Guy. Astronomical Calendar 2013. Raynham, Mass: Universal Workshop, 2012. Print.
- Ottewell, Guy. The Astronomical Companion. 2nd ed. Raynham, Mass: Universal Workshop, 2010. Print.
- Astronomy Magazine. February 2013. Volume 41, No 2.
- Astronomy Magazine. February 2013. Volume 41, No 3.
- Sky & Telescope. February 2013. Volume 125, No 2.
- Sky & Telescope. March 2013. Volume 125, No 3.