Seventh-magnitude 4 Vesta is an easy catch from any location and with any equipment: binoculars or a telescope. Tonight, it’s just 5’ from a magnitude 7.5 field star, creating a temporary artificial double star to enjoy.  You’ll find Vesta in the northwestern corner of Libra, near that constellation’s border with Virgo. It now sits aboutContinue reading "The Sky Today on Saturday, July 19: Vesta forms a double star"

The post The Sky Today on Saturday, July 19: Vesta forms a double star appeared first on Astronomy Magazine.

At 7:15 a.m. EDT on July 14, the crew of Axiom Mission 4 (Ax-4) undocked from the International Space Station, wrapping up an 18-day stay that marked new milestones in commercial and international spaceflight.  The team — led by veteran NASA astronaut and current Axiom Space human spaceflight director Peggy Whitson — splashed down safelyContinue reading "Axiom Mission 4 crew returns to Earth after historic ISS stay"

The post Axiom Mission 4 crew returns to Earth after historic ISS stay appeared first on Astronomy Magazine.

Fernando Oliveira de Menezes from São Paulo, Brazil Globular cluster M4 lies just west of Antares (Alpha [α] Scorpii). To a visual observer, a 6-inch scope reveals dozens of stars; this image comprising 2.6 hours resolves nearly the entire cluster, yielding a star field that feels like you could fall into it. Click to seeContinue reading "Glorious resolution"

The post Glorious resolution appeared first on Astronomy Magazine.

Many faint planetary nebulae went undiscovered for surprisingly long times after Charles Messier and the Herschels stopped cataloguing nebulous objects lying around parts of the sky. It wasn’t until 1980 that two Austrian astronomers, Alois Purgathofer and Ronald Weinberger, found a large, faint planetary nebulae as they searched plates of the Palomar Observatory Sky Survey. Continue reading "Deep-Sky Dreams: PuWe 1   "

The post Deep-Sky Dreams: PuWe 1    appeared first on Astronomy Magazine.

You’ve set your telescope up and are showing people some of the wonders in the sky. Of course, they’re going to ask you questions. Here are some you might be asked. How many do you know the answers to? Question 1: Approximately how old is the universe? Question 2: Which planet in our solar system has theContinue reading "Michael’s Miscellany: 25 Questions About Astronomy"

The post Michael’s Miscellany: 25 Questions About Astronomy appeared first on Astronomy Magazine.

Born on July 18, 1921, John Glenn grew up in Ohio and joined the Marine Corps in 1943. He flew 59 combat missions in World War II and 63 in the Korean War before being selected by NASA for the Mercury program. In 1962, he spent five hours orbiting the Earth in the Friendship 7Continue reading "July 18, 1915: The birth of John Glenn"

The post July 18, 1915: The birth of John Glenn appeared first on Astronomy Magazine.

Titan’s shadow transits the cloud tops of Saturn this morning, beginning around 2:50 A.M. EDT. At that time, Saturn (in the constellation Pisces) should be above the horizon for most of the U.S., with the Last Quarter Moon a good distance away, straddling the border of Pisces and Aries.  Saturn, at magnitude 0.9, is theContinue reading "The Sky Today on Friday, July 18: Titan’s shadow transits"

The post The Sky Today on Friday, July 18: Titan’s shadow transits appeared first on Astronomy Magazine.

Sky This Week is brought to you in part by Celestron. Friday, July 18Mars remains close to Sigma (σ) Leonis, Leo the Lion’s back foot, in the evening sky for several days. Shining at magnitude 1.5, the Red Planet is just over 1° southwest of the 4th-magnitude star tonight.  An hour after sunset, Mars isContinue reading "The Sky This Week from July 18 to 25: Have you seen our interstellar visitor?"

The post The Sky This Week from July 18 to 25: Have you seen our interstellar visitor? appeared first on Astronomy Magazine.

The sky is filled with interesting and unusual planetary nebulae, which give us a forward look at the end state of our own star and solar system. Some of the faintest and most unusual planetaries were discovered long after the NGC and IC catalogs, and so bear strange designations. Such is the case with aContinue reading "Deep-Sky Dreams: Jones-Emberson 1  "

The post Deep-Sky Dreams: Jones-Emberson 1   appeared first on Astronomy Magazine.

In 2021, the United Nations General Assembly declared July 20 International Moon Day, a celebration of our nearest celestial neighbor on the anniversary of the day Apollo 11 landed on the Moon in 1969. The Starmus Festival, founded by astronomer Garik Israelian and astronomer and musician Brian May, is involved with many astronauts and hasContinue reading "Celebrate International Moon Day with Starmus"

The post Celebrate International Moon Day with Starmus appeared first on Astronomy Magazine.

Astronomers are continuing to gather data on 3I/ATLAS, the third confirmed interstellar object (ISO) to pass through our solar system — and possibly the most intriguing yet. Since its discovery on July 1, 2025, new analyses have revealed clues about its origins, composition, age, and potential for future observation. Here’s what the latest research tellsContinue reading "What we know so far about 3I/ATLAS, the interstellar visitor"

The post What we know so far about 3I/ATLAS, the interstellar visitor appeared first on Astronomy Magazine.

The Apollo-Soyuz mission, which occurred 50 years ago this month, was the culmination of a series of fitful attempts at possible international cooperation on human spaceflight. But before one astronaut and one cosmonaut met in an airlock in orbit over the Earth, there were wiretaps and hot dogs, language lessons and vodka toasts. And thoughContinue reading "50 years since the ‘Handshake in Space’: The legacy of Apollo-Soyuz"

The post 50 years since the ‘Handshake in Space’: The legacy of Apollo-Soyuz appeared first on Astronomy Magazine.

After years of planning, training, and international negotiation, the Apollo-Soyuz Test Project mission culminated in 1975 when spacecraft from the U.S. and the Soviet Union docked in space. On July 17, the Apollo and Soyuz capsules locked together, utilizing an “androgynous” system of petal-shaped plates, and their commanders, Thomas Stafford and Aleksey Leonov, shook hands.Continue reading "July 17, 1975: The Apollo-Soyuz Test Project link-up"

The post July 17, 1975: The Apollo-Soyuz Test Project link-up appeared first on Astronomy Magazine.

Gerardo N. Rigiroli from Buenos Aires, Argentina The nebula NGC 3503 in Carina is a stellar nursery that glows brightly at the center of this image, surrounded by ghostly tendrils of gas and dust. At bottom left is the open cluster NGC 3532. The image comprises just over 17 hours of SHORGB data taken withContinue reading "Starbirth in the Keel"

The post Starbirth in the Keel appeared first on Astronomy Magazine.

Mercury stands stationary at 3 A.M. EDT amid the stars of Cancer. The solar system’s smallest planet will now start sliding westward, or retrograde, appearing to “fall” back toward the Sun as it moves through its tight, 88-day orbit.  You can catch Mercury in the evening sky, but only if you’re quick — it’s justContinue reading "The Sky Today on Thursday, July 17: Mercury stands still"

The post The Sky Today on Thursday, July 17: Mercury stands still appeared first on Astronomy Magazine.

On November 23, 2023, a groundbreaking astronomical event unfolded as scientists from the LIGO-Virgo-KAGRA Collaboration detected the most massive black hole merger ever observed. The finding was detailed in a July 13, 2025, press release shared by the University of Birmingham. This cosmic collision occurred when two colossal black holes, approximately 100 and 140 timesContinue reading "Astronomers detect the most massive black hole merger ever"

The post Astronomers detect the most massive black hole merger ever appeared first on Astronomy Magazine.

A newborn planetary system is forming around HOPS-315, a protostar (one that recently formed) that sits some 1,300 light-years away in the constellation Orion the Hunter. This star isn’t in the star-forming region known as the Orion Nebula, however. It lies in a region of space known as the L1630 molecular cloud. Astronomers often seeContinue reading "Astronomers see a new solar system forming for the first time"

The post Astronomers see a new solar system forming for the first time appeared first on Astronomy Magazine.

Planck’s constant is one of the most important numbers in all of physics. It is, essentially, the ultimate guide to the quantum world. It tells us where quantum effects are important, the fundamental energy carried by light and matter, and more. And it all started as an ugly hack. The black body In the lateContinue reading "What is Planck’s constant?"

The post What is Planck’s constant? appeared first on Astronomy Magazine.

The sky is full of interesting and unusual asterisms. If you look around hard enough, or are tired enough, you can convince yourself that you see patterns of stars that resemble practically anything.  But certain asterisms, simply patterns of stars that are composed of members not physically associated with each other, stand out more thanContinue reading "Deep-Sky Dreams: The Broken Engagement Ring"

The post Deep-Sky Dreams: The Broken Engagement Ring appeared first on Astronomy Magazine.

In 1839, the president of Harvard University invited William Bond to move into a house on campus and, by virtue of bringing along his own astronomical equipment, become the university’s first astronomer in residence. With public interest spurred by the 1835 passage of Halley’s Comet and the Comet of 1843, Harvard soon had enough moneyContinue reading "July 16, 1850: Bond and Whipple photograph Vega"

The post July 16, 1850: Bond and Whipple photograph Vega appeared first on Astronomy Magazine.

Chris Schur, taken from Payson, Arizona The interstellar object 3I/ATLAS — just the third to be discovered — is captured in this amateur shot (click and zoom in to see inset) next to the open cluster M23 (at right). The imager used a 10-inch f/3.9 scope to take 30 minutes of LRGB exposure.

The post Interstellar visitor appeared first on Astronomy Magazine.

Author(s): Ryan Wilkinson

A 2D version of a half-metal—a spin-selective electrical conductor—could aid spin-based electronics.

[Physics 18, s85] Published Wed Jul 16, 2025

Author(s): Rachel Berkowitz

A spacecraft observes a new oscillation mode in the low-density plasma.

[Physics 18, s87] Published Wed Jul 16, 2025

Author(s): Rachel Berkowitz

A drone-borne photon counter can provide a new view into environmental health.

[Physics 18, 133] Published Tue Jul 15, 2025

Author(s): David Ehrenstein

Failing to see any high-energy neutrinos allowed researchers to calculate an upper limit on the fraction of high-energy cosmic rays that are protons.

[Physics 18, s96] Published Tue Jul 15, 2025

The now-waning Moon is passing through Pisces in the early-morning sky. Our satellite slides 3° north of Neptune at 6 A.M. EDT, then passes 4° north of Saturn at 7 A.M. EDT. It’s a lovely view for early risers, who can catch the scene in the few hours before dawn. Two hours before sunrise, theContinue reading "The Sky Today on Wednesday, July 16: The Moon hangs with Neptune and Saturn"

The post The Sky Today on Wednesday, July 16: The Moon hangs with Neptune and Saturn appeared first on Astronomy Magazine.

Sotheby’s in New York will be auctioning the largest martian meteorite ever found on Earth on Wednesday as part of a natural history-themed sale. Known as NWA 16788, it was found in Niger in November 2023 by a meteorite hunter. The meteorite, which is red, brown, and gray in color, measures 15 by 11 byContinue reading "The biggest piece of Mars on Earth is up for auction"

The post The biggest piece of Mars on Earth is up for auction appeared first on Astronomy Magazine.

Ron Brecher from Guelph, Ontario, Canada The dwarf galaxy IC 2574 is also known as Coddington’s Nebula, having been discovered by American astronomer Edwin Foster Coddington in 1898, when the nature of galaxies was not yet known. In Hydrogen-alpha light, bright knotty clumps indicate prodigious amounts of star formation. This image comprises just over 17Continue reading "A knotty galaxy"

The post A knotty galaxy appeared first on Astronomy Magazine.

Author(s): Jingcheng Zhou and Chunhui (Rita) Du

Two independent groups optimize diamond-based quantum sensing by using more than 100 such sensors in parallel.

[Physics 18, 132] Published Mon Jul 14, 2025

Born July 15, 1943, Jocelyn Bell Burnell is a British astrophysicist best known for her discovery of pulsars. In 1967, when she was a graduate student in radio astronomy at the University of Cambridge, Bell Burnell noticed “scruff” in the data she was reviewing from the Mullard Radio Astronomy Observatory. Bell Burnell jokingly called thisContinue reading "July 15, 1943: Birth of Jocelyn Bell Burnell"

The post July 15, 1943: Birth of Jocelyn Bell Burnell appeared first on Astronomy Magazine.

The center of the Milky Way is on display during summer evenings, arcing slowly through the southern sky. The galactic center is located near the magnitude 4.5 star 3 Sagittarii, which sits just 4.7° northwest (to the upper right, late this evening if you’re facing south) of Gamma (γ) Sgr, the star at the tipContinue reading "The Sky Today on Tuesday, July 15: Great views of the galactic center"

The post The Sky Today on Tuesday, July 15: Great views of the galactic center appeared first on Astronomy Magazine.

Massimo Tamajo from Syracuse, Sicily, Italy The effects of atmospheric refraction can distort the appearance of the Sun near the horizon — especially when atmospheric inversions are created above an ocean that is cooler than the air above it.

The post Thermal distortions appeared first on Astronomy Magazine.

In a universe governed by turbulence and chaos, perfection is rarely more than a mathematical ideal. Yet astronomers are puzzling over a newfound object that seems to defy that rule: a glowing, nearly flawless circular shell of gas and dust, likely the remnant of a long-dead star, that has remarkably preserved its shape in aContinue reading "Astronomers discover a perfectly spherical supernova remnant"

The post Astronomers discover a perfectly spherical supernova remnant appeared first on Astronomy Magazine.

Mission Highlight: Gilmour Eris Testflight 1 After weeks of delays, Australia is finally poised to join the orbital launch club. Gilmour Space Technologies is expected to debut its Eris rocket with a test launch from Queensland’s Bowen Orbital Spaceport no earlier than (NET) July 16. The three-stage rocket, powered by hybrid engines fueled by aContinue reading "Gilmour aims for orbit again as Starlink surges continue"

The post Gilmour aims for orbit again as Starlink surges continue appeared first on Astronomy Magazine.

In this episode, Astronomy magazine Editor Dave Eicher invites you to head out and observe M4, the wonderful globular cluster in the constellation Scorpius the Scorpion. You can use the Scorpion’s brightest star, 1st-magnitude Antares, as your guide. Although sharp-eyed observers may pick this up with their naked eyes, its swarms of stars look best through aContinue reading "This Week in Astronomy with Dave Eicher: Globular cluster M4"

The post This Week in Astronomy with Dave Eicher: Globular cluster M4 appeared first on Astronomy Magazine.

In a July 10 markup meeting, the Senate Appropriations Committee, responsible for crafting the specific spending bills that allocate federal funds across the government, pushed back against President Trump’s proposed FY2026 budget. The comments signaled bipartisan resistance in the Senate to steep cuts in federal science funding. The president’s proposed budget, released in May, aimedContinue reading "Senate appropriations committee pushes back on 2026 NASA budget cuts"

The post Senate appropriations committee pushes back on 2026 NASA budget cuts appeared first on Astronomy Magazine.

Why will our Sun expel its outer layers as it dies? Daniel StanyerAugusta, Kansas First, let’s discriminate between expansion and expulsion. Expansion happens because the thermal pressure from the increased energy production in the Sun’s interior exceeds the gravitational force keeping the Sun’s matter close to its core. The Sun will expand until a newContinue reading "Why will our Sun expel its outer layers as it dies? "

The post Why will our Sun expel its outer layers as it dies?  appeared first on Astronomy Magazine.

New Horizons launched in January 2006, and by July 14, 2015, it had reached its primary goal: Pluto. The first spacecraft to study Pluto up close, it conducted measurements of Pluto’s atmosphere, mapped the surface geology, observed Pluto’s moons. New Horizons also investigated the dwarf planet’s interior structure, adding support to the theory that PlutoContinue reading "July 14, 2015: New Horizon arrives at Pluto"

The post July 14, 2015: New Horizon arrives at Pluto appeared first on Astronomy Magazine.

Saturn stands stationary amid the stars of Pisces at 4 A.M. EDT. It is followed two hours later by asteroid 3 Juno, which reaches its stationary point in Libra at 6 A.M. EDT.  Only Saturn is visible in the morning sky, while Juno is up after sunset. Starting in the morning, look for magnitude 0.9Continue reading "The Sky Today on Monday, July 14: Saturn and Juno are stationary"

The post The Sky Today on Monday, July 14: Saturn and Juno are stationary appeared first on Astronomy Magazine.

On July 13, 1969, the Soviet Union launched Luna 15, an unmanned spacecraft seen as a rival to the American Apollo 11 mission, which launched just three days later. Luna 15’s goal was to land on the Moon, collect rock samples, and return to Earth before the Apollo astronauts. But the heightened moment of competitionContinue reading "July 13, 1969: Luna 15 launches"

The post July 13, 1969: Luna 15 launches appeared first on Astronomy Magazine.

Venus passes 3° north of Aldebaran in Taurus at midnight EDT; the pair is visible in the early-morning sky, well positioned in the east for two hours before sunrise.  Venus is notably brighter — magnitude –4.1, far outshining magnitude 0.9 Aldebaran, the brightest star in the Taurus and cataloged as Alpha (α) Tauri. Together, theContinue reading "The Sky Today on Sunday, July 13: The Bull has two eyes"

The post The Sky Today on Sunday, July 13: The Bull has two eyes appeared first on Astronomy Magazine.

Author(s): Michael Schirber

A detailed analysis of a stellar cluster has led to a possible explanation for several fast-moving runaway stars around the cluster.

[Physics 18, 134] Published Fri Jul 11, 2025

Author(s): Charles Day

An arrangement of spins known as a meron turns out to be easier to make in momentum space than in real space.

[Physics 18, s91] Published Thu Jul 10, 2025

The Soviet Union launched Phobos 2 on July 12, 1988, the second of two uncrewed probes designed to study Mars, moons Phobos and Deimos, the Sun, and the interplanetary environment. Each probe was equipped with 25 instruments including high-energy detectors; X-ray and solar photometers; infrared, ultrasound, and gamma-ray spectrometers; and more. Phobos 1 was lostContinue reading "July 12, 1988: Phobos 2 launches"

The post July 12, 1988: Phobos 2 launches appeared first on Astronomy Magazine.

Already high in the east an hour after sunset is the constellation Lyra the Lyre, easy to locate thanks to its brightest star, magnitude 0 Vega. Tonight, we’re looking southeast of this star at M56, an 8th-magnitude globular cluster in near the border of Lyra and Cygnus. In fact, one of the easiest ways toContinue reading "The Sky Today on Saturday, July 12: M56 in Lyra"

The post The Sky Today on Saturday, July 12: M56 in Lyra appeared first on Astronomy Magazine.

Xiaofeng Qu, taken from Lijiang, Yunnan, China The Geminid meteor shower appears to rain down upon the Gaomeigu Astronomical Observatory (altitude: 10,500 feet [3,200 meters]) in this carefully composed 10-panel panorama. Also visible are numerous Hα features glowing across the sky, like the Orion Loop just above the observatory dome. The imager used 4 NikonContinue reading "High-altitude shower"

The post High-altitude shower appeared first on Astronomy Magazine.

I thought I’d write a bit about several eye-related topics. First up is resolution, which is the ability to see details in objects. We have decreased resolution at night, and little color vision as well, for multiple reasons: reduced numbers of retinal cells firing, the color shift in sensitivity vs. the focus ability of theContinue reading "Michael’s Miscellany: The Eyes Have It"

The post Michael’s Miscellany: The Eyes Have It appeared first on Astronomy Magazine.

There is a battle brewing over ownership of a retired NASA space shuttle. The One Big Beautiful Bill Act, signed into law by President Donald Trump at the White House last week, sets aside $85 million to relocate the space shuttle Discovery from its current home at the National Air and Space Museum’s Steven F. Udvar-Hazy Center in northernContinue reading "Smithsonian pushing back on plans to relocate space shuttle"

The post Smithsonian pushing back on plans to relocate space shuttle appeared first on Astronomy Magazine.

On July 11, 1801, French astronomer Jean-Louis Pons made his first comet discovery, c/1801 N1. When he’d began his career in 1789 as a doorkeeper (essentially, a concierge) at Marseille Observatory, the directors had recognized his talents and taught him more about astronomy. That background, combined with his exceptional observational skills and the ability toContinue reading "July 11, 1801: Jean-Louis Pons finds his first comet"

The post July 11, 1801: Jean-Louis Pons finds his first comet appeared first on Astronomy Magazine.

There’s a demon in the early-morning sky, amid the stars of Perseus the Hero. Second-magnitude Algol (Beta Persei) is also famously known as the Demon Star, and you can spot it two hours before sunrise, standing 30° high in the east, to the upper left of the Pleiades.  Algol is dubbed a demon because everyContinue reading "The Sky Today on Friday, July 11: The demon in the morning sky"

The post The Sky Today on Friday, July 11: The demon in the morning sky appeared first on Astronomy Magazine.

Sky This Week is brought to you in part by Celestron. Friday, July 11The Moon passes just 0.02° north of the dim, distant dwarf planet Pluto at 7 P.M. EDT. However, the bright light from our satellite will make Pluto — already a challenging object requiring the largest amateur instruments — even more difficult toContinue reading "The Sky This Week from July 11 to 18: The Moon hangs with Saturn and Neptune"

The post The Sky This Week from July 11 to 18: The Moon hangs with Saturn and Neptune appeared first on Astronomy Magazine.

President Donald Trump announced Wednesday evening that U.S. Secretary of Transportation Sean Duffy would serve as an “interim administrator” of NASA. “He will be a fantastic leader of the ever more important Space Agency, even if only for a short period of time,” Trump said in a post on Truth Social, his social media platform.Continue reading "Trump taps Transportation Secretary Sean Duffy as ‘interim’ NASA head"

The post Trump taps Transportation Secretary Sean Duffy as ‘interim’ NASA head appeared first on Astronomy Magazine.

Chuck Ayoub from Redford, MI Globular cluster M53 in Coma Berenices (at right) is accompanied by fainter NGC 5053 (at left). Astronomers have reported evidence for a tidal tail, suggesting the pair have interacted in the past. The imager took 2.5 hours of exposure with a Celestron RASA 8-inch f/2 scope and a one-shot colorContinue reading "An ancient pair"

The post An ancient pair appeared first on Astronomy Magazine.

Quasars were a mystery when first discovered in the early 1960s. They are extremely distant, starlike objects that emit enormous amounts of energy. Years later, astronomers understood that quasars are the extremely energetic centers of young galaxies, powered by supermassive black holes. The fact that they are mostly young (the black holes generally quiet downContinue reading "Deep-Sky Dreams: NGC 3079 and Quasar 0957+561   "

The post Deep-Sky Dreams: NGC 3079 and Quasar 0957+561    appeared first on Astronomy Magazine.

Few authors have had as big an impact on space journalism as Jeffrey Kluger. His 1994 book Lost Moon, co-authored with Astronaut James Lovell, was the basis for the 1995 film Apollo 13, which starred Tom Hanks and was directed by Ron Howard. Other books by Kluger have focused on the flight of Apollo 8 and NASA’s unmannedContinue reading "Behind the scenes of NASA’s Project Gemini: Astronomy chats with Jeffrey Kluger"

The post Behind the scenes of NASA’s Project Gemini: Astronomy chats with Jeffrey Kluger appeared first on Astronomy Magazine.

Inventor Nikola Tesla was born July 10, 1856, in what is now Croatia (then part of the Austrian Empire). In 1899, Tesla recorded cosmic radio waves in his Colorado Springs, Colorado, laboratory. Though he believed the waves were extraterrestrial signals from another planet, today we know that they are part of the spectrum of anContinue reading "July 10, 1856: The birth of Nicola Tesla"

The post July 10, 1856: The birth of Nicola Tesla appeared first on Astronomy Magazine.

Author(s): Charles Day

A mechanism for accelerating charged particles in astrophysical plasmas has been reproduced with cold atoms in an optical trap.

[Physics 18, 131] Published Wed Jul 09, 2025

Author(s): Ryan Wilkinson

A new algorithm efficiently ranks competitors in settings ranging from sports tournaments to food-preference surveys.

[Physics 18, s80] Published Wed Jul 09, 2025

Author(s): Susan Curtis

Experiments with turbulent waves show that energy spreads from small to large scales, producing a steady-state regime that can be described using classical thermodynamics.

[Physics 18, 129] Published Tue Jul 08, 2025

Author(s): Ryan Wilkinson

A fluid made of light can simulate a black hole’s boundary, providing insights into the mysterious quantum phenomena that occur at such a boundary.

[Physics 18, s92] Published Tue Jul 08, 2025

Full Moon occurs at 4:37 P.M. EDT this afternoon and will rise in the southeast around the time the Sun is setting in the northwest. The July Full Moon is also called the Buck Moon, and this month our satellite also rises at its farthest point south in 18.6 years: some 7° more southerly thanContinue reading "The Sky Today on Thursday, July 10: The Full Buck Moon swings low"

The post The Sky Today on Thursday, July 10: The Full Buck Moon swings low appeared first on Astronomy Magazine.