Jump to content

July’s Night Sky Notes: A Hero, a Crown, and Possibly a Nova!


Recommended Posts

  • Publishers
Posted
3 Min Read

July’s Night Sky Notes: A Hero, a Crown, and Possibly a Nova!

A globular cluster of thousands of stars, mainly white and yellow with small blue stars intermixed.
Like shiny flakes sparkling in a snow globe, over 100,000 stars whirl within the globular cluster M13, one of the brightest star clusters visible from the Northern Hemisphere. Located 25,000 light-years from Earth with an apparent magnitude of 5.8, this glittering metropolis of stars in the constellation Hercules can be spotted with a pair of binoculars most easily in July.
Credits:
NASA

by Vivan White of the Astronomical Society of the Pacific

High in the summer sky, the constellation Hercules acts as a centerpiece for late-night stargazers. At the center of Hercules is the “Keystone,” a near-perfect square shape between the bright stars Vega and Arcturus that is easy to recognize and can serve as a guidepost for some amazing sights. While not the brightest stars, the shape of the hero’s torso, like a smaller Orion, is nearly directly overhead after sunset. Along the edge of this square, you can find a most magnificent jewel – the Great Globular Cluster of Hercules, also known as Messier 13.

jul24-hercules-tcrb.jpg?w=896
Look up after sunset during summer months to find Hercules! Scan between Vega and Arcturus, near the distinct pattern of Corona Borealis. Once you find its stars, use binoculars or a telescope to hunt down the globular clusters M13 (and a smaller globular cluster M92). If you enjoy your views of these globular clusters, you’re in luck – look for another great globular, M3, near the constellation Boötes.
Credit: Stellarium

Globular clusters are a tight ball of very old stars, closer together than stars near us. These clusters orbit the center of our Milky Way like tight swarms of bees. One of the most famous short stories, Nightfall by Isaac Asimov, imagines a civilization living on a planet within one of these star clusters. They are surrounded by so many stars so near that it is always daytime except for once every millennium, when a special alignment (including a solar eclipse) occurs, plunging their planet into darkness momentarily. The sudden night reveals so many stars that it drives the inhabitants mad.

Back here on our home planet Earth, we are lucky enough to experience skies full of stars, a beautiful Moon, and regular eclipses. On a clear night this summer, take time to look up into the Keystone of Hercules and follow this sky chart to the Great Globular Cluster of Hercules. A pair of binoculars will show a faint, fuzzy patch, while a small telescope will resolve some of the stars in this globular cluster.

Artist rendition of a red giant star and white dwarf orbiting each other.
A red giant star and white dwarf orbit each other in this animation of a nova similar to T Coronae Borealis. The red giant is a large sphere in shades of red, orange, and white, with the side facing the white dwarf the lightest shades. The white dwarf is hidden in a bright glow of white and yellows, which represent an accretion disk around the star. A stream of material, shown as a diffuse cloud of red, flows from the red giant to the white dwarf. When the red giant moves behind the white dwarf, a nova explosion on the white dwarf ignites, creating a ball of ejected nova material shown in pale orange. After the fog of material clears, a small white spot remains, indicating that the white dwarf has survived the explosion.
NASA/Goddard Space Flight Center

Bonus! Between Hercules and the ice-cream-cone-shaped Boötes constellation, you’ll find the small constellation Corona Borealis, shaped like the letter “C.” Astronomers around the world are watching T Coronae Borealis, also known as the “Blaze Star” in this constellation closely because it is predicted to go nova sometime this summer. There are only 5 known nova stars in the whole galaxy. It is a rare observable event and you can take part in the fun! The Astronomical League has issued a Special Observing Challenge that anyone can participate in. Just make a sketch of the constellation now (you won’t be able to see the nova) and then make another sketch once it goes nova.

Tune into our mid-month article on the Night Sky Network page, as we prepare for the Perseids! Keep looking up!

View the full article

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Topics

    • By NASA
      NASA/Kim Shiflett NASA astronauts Christina Koch, Artemis II mission specialist, and Victor Glover, Artemis II pilot, walk on the crew access arm of the mobile launcher in the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on Tuesday, Aug. 12, 2025.
      On Aug. 11 and 12, teams with the agency’s Exploration Ground Systems Program along with NASA astronauts Reid Wiseman, Victor Glover, and Christina Koch, and CSA (Canadian Space Agency) astronaut Jeremy Hansen, practiced launch day operations if launch occurs at night. They simulated putting their spacesuits on and driving to the launch pad as well as emergency procedures they would use in the unlikely event of an emergency during the launch countdown requiring them to evacuate the launch pad.
      Through the Artemis campaign, NASA will send astronauts to explore the Moon for scientific discovery, economic benefits, and to build the foundation for the first crewed missions to Mars.
      Image credit: NASA/Kim Shiflett
      View the full article
    • By NASA
      1 min read
      NASA’s Black Marble: Stories from the Night Sky
      Earth (ESD) Earth Explore Explore Earth Home Air Quality Climate Change Freshwater Life on Earth Severe Storms Snow and Ice The Global Ocean Science at Work Earth Science at Work Technology and Innovation Powering Business Multimedia Image Collections Videos Data For Researchers About Us Viewed from space, Earth at night tells endless stories. Using satellite data, we can track population growth, natural disaster damage, cultural celebrations, and even space weather. Studying these glowing patterns helps us understand human activity, respond to disasters, and witness a changing world.

      Original Video and Assets

      Share








      Details
      Last Updated Aug 04, 2025 Related Terms
      Earth Video Series Explore More
      4 min read NUBE: New Card Game Helps Learners Identify Cloud Types Through Play


      Article


      3 days ago
      6 min read NASA’s TRACERS Studies Explosive Process in Earth’s Magnetic Shield


      Article


      3 weeks ago
      2 min read Polar Tourists Give Positive Reviews to NASA Citizen Science in Antarctica


      Article


      4 weeks ago
      Keep Exploring Discover More Topics From NASA
      Earth


      Your home. Our Mission. And the one planet that NASA studies more than any other.


      Explore Earth Science



      Earth Science in Action


      NASA’s unique vantage point helps us inform solutions to enhance decision-making, improve livelihoods, and protect our planet.


      Earth Multimedia & Galleries


      View the full article
    • By USH
      3I/ATLAS as an interstellar visitor, discovered on July 1. Estimated to be up to 15 miles (24 kilometers) wide, it’s barreling toward the Sun at over 130,000 mph. Fortunately, it won’t come closer to Earth than 1.6 astronomical units — about 150 million miles (240 million kilometers) according to NASA. 

      NASA insists there's no reason for concern — it’s just a comet, end of story. But here's where things get interesting: 3I/ATLAS is the third known interstellar object to enter our solar system, following the enigmatic ‘Oumuamua in 2017 and comet Borisov in 2019. And like those two, it behaves in ways that deviate from what we expect of natural comets. 
      A newly published paper on the preprint server arXiv (July 16) challenges NASA’s official explanation. The study, co-authored by three scientists, including Harvard astrophysicist Avi Loeb, suggests that 3I/ATLAS might not be a comet at all. Instead, the team proposes it could be an artificial object: a surveillance probe sent by an unknown extraterrestrial intelligence, possibly even one with hostile intent. 
      Loeb, warns that if this hypothesis turns out to be accurate, the consequences for humanity could be profound. He suggests that preparing defensive countermeasures might be necessary if this object poses a real threat. 
      What makes 3I/ATLAS so unusual? 
      According to Loeb, the object’s trajectory is so rare that the odds of a natural comet following the same path are less than 0.005%. 
      It will pass unusually close to three planets — Venus, Mars, and Jupiter — raising further suspicion. 
      Most telling of all: 3I/ATLAS lacks a coma, the cloud of gas and dust that typically surrounds comets. 
      "When analyzed with an open mind, the data offers compelling evidence that 3I/ATLAS may be technological in nature," Loeb explained. 
      In fact, Loeb outlines eight specific reasons why this object likely isn't a natural interstellar visitor — and why it may be of artificial origin. (You can read his full breakdown (here). 
      The idea that this mysterious object might be an alien craft, possibly one preparing for closer contact with Earth, is unsettling to say the least. For now, we can only wait, watch... and wonder. View the full article
    • By NASA
      As the Sun approaches the most active part of its eleven-year magnetic cycle this summer, NASA volunteers have been watching it closely. Now they’ve spotted a new trend in solar behavior that will have you reaching for your suntan lotion. It’s all about something called a “Type II” solar radio burst:
      “Type II solar radio bursts are not commonly detected in the frequency range between 15 to 30 megahertz,” said Prof. Chuck Higgins, Co-founder of Radio JOVE. “Recently, we’re seeing many of them in that range.”
      Let’s unpack that. Our Sun often sprays powerful blasts of radio waves into space. Heliophysicists classify these radio bursts into five different types depending on how the frequency of the radio waves drifts over time. “Type II” solar radio bursts seem to come from solar flares and enormous squirts of hot plasma called coronal mass ejections.
      Now, Thomas Freeman, an undergraduate student at Middle Tennessee State University, and other volunteers working on NASA’s Radio JOVE project have observed something interesting about these Type II bursts: they are now showing up at lower frequencies—somewhere in between FM and AM radio. 
      What does it mean? It means our star is full of surprises! These Radio JOVE observations of the Sun’s radio emissions during solar maximum can be used to extend our knowledge of solar emissions to lower frequencies and, therefore, to distances farther from the Sun. 
      Radio JOVE is a NASA partner citizen science project in which participants assemble and operate radio astronomy telescopes to gather and contribute data to support scientific studies.  Radio JOVE collaborated with SunRISE Ground Radio Lab,  organized teams of high school students to observe the Sun, and recently published a paper on these Type II solar radio bursts. Learn more and get involved!  
      A Type II solar radio burst on April 23rd, 2024, seen as the gently sloping yellow band drifting from 17:49 to 18:02 UTC in the 15-30 MHz radio frequency-time spectrogram. Credit: Tom Ashcraft, Lamy, NM Share








      Details
      Last Updated Jul 23, 2025 Related Terms
      Citizen Science Heliophysics Explore More
      2 min read Bring NASA Science into Your Library!


      Article


      2 days ago
      4 min read NASA to Launch SNIFS, Sun’s Next Trailblazing Spectator
      July will see the launch of the groundbreaking Solar EruptioN Integral Field Spectrograph mission, or…


      Article


      6 days ago
      6 min read NASA’s TRACERS Studies Explosive Process in Earth’s Magnetic Shield


      Article


      7 days ago
      View the full article
    • By Amazing Space
      Solar Storm Latest - What Happened Last Night? July 7th
  • Check out these Videos

×
×
  • Create New...