The night sky tonight and on any clear night offers an ever-changing display of fascinating objects you can see, from stars and constellations to bright planets, often the moon, and sometimes special events like meteor showers. Observing the night sky can be done with no special equipment, although a sky map can be very useful, and a good beginner telescope or binoculars will enhance some experiences and bring some otherwise invisible objects into view. You can also use astronomy accessories to make your observing easier, and use our Satellite Tracker page powered by N2YO.com to find out when to see the International Space Station and other satellites. Below, find out what's up in the night sky tonight (Planets Visible Now, Moon Phases, Observing Highlights This Month) plus other resources (Skywatching Terms, Night Sky Observing Tips and Further Reading).
Monthly skywatching information is provided to Space.com by Chris Vaughan of Starry Night Education, the leader in space science curriculum solutions. Follow Starry Night on Twitter @StarryNightEdu.
Editor's note: If you have an amazing skywatching photo you'd like to share for a possible story or image gallery, you can send images and comments in to email@example.com.
Yearly Night Sky Guides:
- When, Where and How to See the Planets in the 2019 Night Sky
- The Top Skywatching Events to Look for in 2019
- Best Night Sky Events of August's 2019 (Stargazing Maps)
- Space Launch Calendar 2019: Sky Events, Missions & More
Calendar of Observing Highlights
Thursday, August 1 — Young Moon Meets Mars
Low in the west-northwestern sky for a brief period after sunset on Thursday, August 1, the very slim crescent of the young moon will appear less than two finger widths above (celestial northeast of) dim, reddish Mars. This pairing will favor skywatchers situated at low latitudes, where the sky surrounding the objects will be darker. Ensure that the sun has completely disappeared below the horizon before using binoculars (red circle) or a telescope in that area of the sky.
Wednesday, August 7 at 17:31 GMT — First Quarter Moon
After the moon has completed the first quarter of its orbit around Earth, the relative positions of the Earth, sun, and moon cause us to see it half-illuminated - on its eastern side. A first quarter moon always rises around noon and sets around midnight, so it is also visible in the afternoon daytime sky. The evenings around first quarter are the best times to see the lunar terrain when it is dramatically lit by low-angled sunlight.
Friday, August 9 — Waxing Moon close to Jupiter
In the southern sky on the evening of Friday, August 9, the waxing gibbous moon will land just to the upper left (celestial northeast) of the bright planet Jupiter. Both objects will fit within the field of view of binoculars (red circle). If you watch the pair over several hours, starting at dusk, you will see the moon's orbit carry it farther from the planet.
Friday, August 9 pre-dawn — Mercury at Greatest Western Elongation
On Friday, August 9, Mercury (orbit shown as a red curve) will reach an angle of 19 degrees west of the Sun, its widest separation for this apparition. Due to the steeply dipping morning ecliptic (green line), this will be a good pre-dawn apparition for Northern Hemisphere skywatchers, but a poor one for those viewing the planet from the Southern Hemisphere.
Sunday, August 11 evening — Jupiter Reverses Direction
On Sunday, August 11, Jupiter will end a westerly retrograde loop (red path) that began in April, and resume its regular eastward motion with respect to the distant stars of southern Ophiuchus. If you take note of Jupiter's position with respect to the bright star Antares, and check back every week or two, Jupiter's orbital motion will be apparent.
Sunday, August 11 — Bright Moon near Saturn
In the southeastern sky after dusk on Sunday evening, August 11, the bright, yellowish planet Saturn will be positioned 4 degrees to the left (east) of the bright, waxing gibbous moon. The pair will cross the sky together for most of the night and will easily appear together within the field of binoculars (red circle). If you watch the pair over several hours, starting at dusk, you will see the moon's orbit carry it closer to the planet and the rotation of the sky lift Saturn higher than the moon. Observers in eastern Indonesia, most of Australia, northern New Zealand, Melanesia, and Polynesia (except Hawaii) will see the moon occult Saturn on August 12.
Monday, August 12 from 9:07 to 11:20 p.m. EDT — Io's Black Shadow on Jupiter
From time to time, the little round, black shadows cast by Jupiter's four Galilean moons become visible in backyard telescopes as they cross (or transit) the planet's disk. On Monday, August 12 from 9:07 to 11:20 p.m. EDT, observers in the Americas can watch Io's shadow transit Jupiter.
Monday, August 12 after midnight — Uranus Reverses Direction
On Monday, August 12, Earth's faster orbit will cause Uranus to cease its eastward motion (inset with red path) with respect to the distant stars and begin a westward retrograde loop that will last until mid-January, 2020. Look for the bluish-green, magnitude 5.8 planet in southwestern Aries, sitting less than 5 degrees above (celestial north of) the naked-eye star Al Kaff al Jidhmah (Xi Ceti).
Tuesday, August 12-13 overnight — Perseid Meteor Shower Peak
The Perseid meteor shower, which runs annually between July 13 and August 26, will peak before dawn on Tuesday, August 13. The best time for seeing Perseid meteors starts after midnight, when the shower's radiant is higher in the northeastern sky. Derived from debris dropped by Comet Swift-Tuttle, it is always the most reliable shower of the year, delivering up to 100 meteors per hour at the peak. This year, the waxing gibbous moon phase around the peak nights will greatly reduce the number of meteors we'll see.
Thursday, August 15 at 12:29 GMT — Full Green Corn Moon
The August full moon, known as the "Sturgeon Moon", "Red Moon", "Green Corn Moon", and "Grain Moon", always shines among or near the stars of Aquarius or Capricornus. Full moons always rise at sunset and set at sunrise. Since this full moon phase will occur in the morning daylight hours, the moon will appear to be full on both Wednesday and Thursday evening in the Americas.
Friday, August 16 — Spot Asteroid Vesta
In the post-midnight hours of Friday, August 16, the main belt asteroid Vesta will be positioned midway between two medium-bright stars in Taurus, allowing for amateur skywatchers to easily find the asteroid in binoculars and backyard telescopes. The magnitude 7.9 asteroid will be dimmer than the two stars that flank it. The magnitude 4.1 star designated f Tauri will sit 2 degrees to Vesta's upper left, while the brighter star o Tauri will be positioned 2 degrees to Vesta's lower right. Over the subsequent two nights, Vesta's orbital motion (red path) will carry it to the lower left of those two stars, passing within 0.25 degrees of the star designated 4 Tauri on August 18-19.
Saturday, August 17 from 8:53 to 11:25 p.m. EDT — Europa's Black Shadow on Jupiter
From time to time, the little round, black shadows cast by Jupiter's four Galilean moons become visible in backyard telescopes as they cross (or transit) the planet's disk. On Saturday, August 17 from 8:53 to 11:25 p.m. EDT, observers in the Americas can watch Europa's shadow transit the northern hemisphere of Jupiter.
Tuesday, August 20 at 10 p.m. EDT — Algol at Minimum Brightness
The "Demon Star" Algol in Perseus is among the most accessible variable stars for beginner skywatchers. Its naked-eye brightness dims noticeably for about 10 hours once every 2 days, 20 hours, and 49 minutes because a dim companion star orbiting nearly edge-on to Earth crosses in front of the much brighter main star. On Tuesday, August 20 at 10 p.m. EDT, Algol will reach its minimum brightness of magnitude 3.4 and will sit just above the northeastern horizon. By 3 a.m. EDT, it will be more than halfway up the eastern sky and will have brightened to its usual magnitude of 2.1.
Wednesday, August 21 pre-dawn — Waning Moon meets Uranus
In the southern pre-dawn sky on Wednesday, August 21, the waning gibbous moon will be positioned 6.5 degrees to the lower right (celestial southwest) of the blue-green planet Uranus. The slow-moving planet can be found by looking less than 5 degrees above (celestial north of) the faint, naked-eye star Xi Ceti.
Friday, August 23 at 14:56 GMT — Last Quarter Moon
At its last quarter phase, the moon rises around midnight and remains visible in the southern sky all morning. At this phase, the moon is illuminated on its western side, towards the pre-dawn sun. Last quarter moons are positioned ahead of the Earth in our trip around the sun. About 3.5 hours later, Earth will occupy that same location in space. After this phase, the waning moon traverses the last quarter of its orbit around the earth, on the way to new moon.
Monday, August 26 evening — Jupiter Flies through a Globular Cluster
On the evenings surrounding Monday, August 26, Jupiter's apparent motion (red path) will carry it close past a magnitude 7.2 globular star cluster designated NGC 6235 (inset), which is located in the southern sky in the constellation of Ophiuchus. At closest approach on August 26, the bright planet will sit only 2 arc-minutes below (south of) the cluster. (For comparison purposes, the full moon is 30 arc-minutes across.) The cluster is located about 38,000 light-years away, while Jupiter will only be 38 light-minutes from Earth! Both objects will fit within the field of view of a backyard telescope at high power (red circle). To better see the dim, fuzzy globular cluster, try placing Jupiter just outside your field of view.
Wednesday, August 28 before dawn — Moon Buzzes the Beehive
Low in the east-northeastern sky just before dawn on Wednesday, August 28, the delicate crescent of the old moon will land on the outskirts of the large open star cluster known as the Beehive and Messier 44. The best viewing time will land between 4:30 and 5:30 a.m. local time. If you place the moon in your binoculars, the cluster's stars will be sprinkled below the moon.
Friday, August 30 at 10:37 GMT — New Moon and Large Tides
At its new phase, the moon is travelling between Earth and the sun. Since sunlight is only reaching the far side of the moon, and the moon is in the same region of the sky as the sun, the moon will be completely hidden from view. Because the moon's closest approach to Earth (perigee) will occur only 5.5 hours after the moon's new phase, the combined gravitational tugs of the sun and moon pulling from the same direction in space will generate large tides on Earth for several days.
Mercury will spend all of August in the eastern pre-dawn sky, but it will only be observable with relative ease until the final week of the month. Due to the steeply dipping morning ecliptic, this will be a good apparition for Northern Hemisphere skywatchers, but a poor one for those viewing the planet from the Southern Hemisphere. As August begins, Mercury will be climbing away from the soon-to-rise sun, and will show a slim crescent in backyard telescopes. The best time to look for the swift planet will fall between 5:15 and 5:30 a.m. local time. For the rest of the month, Mercury will brighten dramatically from magnitude 1.9 to -1.7. Its disk will increase in illuminated phase and diminish in apparent diameter as the Mercury-Earth separation distance increases. On August 9, Mercury, now half-illuminated, will reach its widest separation angle of 19 degrees west of the Sun, allowing it to be seen for a longer period of time — approximately 5 to 5:45 a.m. local time. Mercury will slide past the southern edge of the Beehive Cluster (Messier 44) on August 17, but the sky will be too bright for observers at higher latitudes to see the cluster's stars.
During August, Venus will be out of sight near the sun. It will pass solar conjunction on August 14, and then re-appear in the western evening sky in September.
Mars will spend August in the western evening sky among the stars of Leo. But the red planet will only be visible with difficulty on the opening days of the month, as it swings steadily towards the sun and solar conjunction in early September. For a brief period after sunset on August 1, look low in the northwestern sky for the very slim crescent of the young moon positioned less than two degrees above (celestial northeast of) Mars.
Extremely bright Jupiter will continue to be a fine evening observing target during August. As Earth moves farther from it, the planet will decrease slightly in brightness (from magnitude -2.41 to -2.22) and apparent disk size (from 42.5 to 39 arc-seconds). On August 11, Jupiter will end a westerly retrograde loop that began in April, and resume its regular eastward motion with respect to the distant stars of southern Ophiuchus. On the evenings surrounding August 26, Jupiter will make a close pass of a globular star cluster designated NGC 6235. At closest approach on August 26, the bright planet will sit only 2 arc-minutes above the cluster. In the southern sky on the evening of August 9, the waxing gibbous moon will be positioned to the upper left (celestial northeast) of Jupiter. From time to time, the little round shadows cast by Jupiter's four Galilean moons will be visible as they cross the planet's disk. On August 12 from 9:07 to 11:20 p.m. EDT, observers in the Americas can watch Io's shadow transit Jupiter. On August 17 from 8:53 to 11:25 p.m. EDT, Europa's shadow will transit the northern hemisphere of Jupiter.
Fresh from opposition in July, Saturn will be well-positioned for observing all night during August as it moves retrograde (westward) through the stars of northern Sagittarius. Look for it as a medium-bright, yellowish object in the lower part of the southeastern sky - a half-dozen degrees east of the Milky Way. Over the course of the month, Earth's increasing distance from the ringed planet will cause Saturn to diminish slightly in brightness and apparent size. On August 11, the bright, waxing gibbous moon will be positioned 4 degrees to the right (west) of Saturn. Observers in eastern Indonesia, most of Australia, northern New Zealand, Melanesia, and Polynesia (except Hawaii) will see the moon occult Saturn on August 12.
As August begins, blue-green Uranus (magnitude 5.8) is transitioning from a post-midnight object to an evening object — eventually rising at 10 p.m. local time by month-end. On August 12, Earth's faster orbit will cause Uranus to cease its eastward motion with respect to the distant stars of southwestern Aries, and begin a westward retrograde loop that will last until mid-January, 2020. The slow-moving planet can be found by looking less than 5 degrees above (celestial north of) the faint, naked-eye star Xi Ceti. In the southern pre-dawn sky on August 21, the waning gibbous moon will be positioned 6.5 degrees to the lower right (southwest) of Uranus.
During August, Blue-tinted Neptune (magnitude 7.8) will be visible from late evening onward in the southeastern and southern sky - moving retrograde (westward) among the stars of eastern Aquarius. The planet will be shifting steadily toward that constellation's naked-eye star Phi (φ) Aquarii. On August 1, Neptune will be positioned 1 degree to the left (east) of that star. By month-end it will have moved to within 9 arc-minutes east of it.
Gibbous: Used to describe a planet or moon that is more than 50% illuminated.
Asterism: A noteworthy or striking pattern of stars within a larger constellation.
Degrees (measuring the sky): The sky is 360 degrees all the way around, which means roughly 180 degrees from horizon to horizon. It's easy to measure distances between objects: Your fist on an outstretched arm covers about 10 degrees of sky, while a finger covers about one degree.
Visual Magnitude: This is the astronomer's scale for measuring the brightness of objects in the sky. The dimmest object visible in the night sky under perfectly dark conditions is about magnitude 6.5. Brighter stars are magnitude 2 or 1. The brightest objects get negative numbers. Venus can be as bright as magnitude minus 4.9. The full moon is minus 12.7 and the sun is minus 26.8.
Terminator: The boundary on the moon between sunlight and shadow.
Zenith: The point in the sky directly overhead.
Night Sky Observing Tips
Adjust to the dark: If you wish to observe faint objects, such as meteors or dim stars, give your eyes at least 15 minutes to adjust to the darkness.
Light Pollution: Even from a big city, one can see the moon, a handful of bright stars and sometimes the brightest planets. But to fully enjoy the heavens — especially a meteor shower, the constellations, or to see the amazing swath across the sky that represents our view toward the center of the Milky Way Galaxy — rural areas are best for night sky viewing. If you're stuck in a city or suburban area, a building can be used to block ambient light (or moonlight) to help reveal fainter objects. If you're in the suburbs, simply turning off outdoor lights can help.
Prepare for skywatching: If you plan to be out for more than a few minutes, and it's not a warm summer evening, dress warmer than you think necessary. An hour of observing a winter meteor shower can chill you to the bone. A blanket or lounge chair will prove much more comfortable than standing or sitting in a chair and craning your neck to see overhead.
Daytime skywatching: When Venus is visible (that is, not in front of or behind the sun) it can often be spotted during the day. But you'll need to know where to look. A sky map is helpful. When the sun has large sunspots, they can be seen without a telescope. However, it's unsafe to look at the sun without protective eyewear. See our video on how to safely observe the sun, or our safe sunwatching infographic.
- Moon Phases: How the lunar cycle works, from full moon to new moon. Also find out when is the next full moon.
- Constellations: The history of the Zodiac constellations and their place in night sky observing.
- Lunar Eclipses: How they work, plus find out when's the next lunar eclipse.
- Solar Eclipses: How they work, the types, and when the next one occurs.