Venus is something of a frustration for stargazers. It’s the brightest planet and the easiest to see, while the sight of it close to a crescent moon is one of the most achingly beautiful sights in the sky. Yet it gives almost nothing away.

Mars has its reddish color. Saturn rewards even a small telescope with its spectacular rings. Jupiter has moons, belts and an obvious disk. Venus, meanwhile, spends months blazing away in twilight looking exactly like what people who do not stargaze assume a star should look like — a brilliant white point. What we’re seeing is sunlight reflected by its global cloud cover, which in turn makes it impossible to see in any detail.

But every now and then, it does something revealing by becoming a crescent. That is when Venus, an inner planet relative to Earth, finally makes sense.

Put a small telescope on Venus this week and its appearance is completely different from the dazzling dot seen with the naked eye. This week, its disk will dim from 36% to 32% lit as it shrinks toward a thinner crescent as September progresses. At the same time, its apparent disk is getting larger because Venus is moving closer to Earth.

Those two changes are connected. Venus reached its greatest eastern elongation, about 46 degrees from the sun, on Aug. 15. It’s now swinging around the inside of its smaller, faster orbit of the sun towards inferior conjunction on Oct. 24, when it will pass roughly between Earth and the sun, and be lost in the sun’s glare. Before that, it will reach its peak — greatest brilliancy — in the evening sky on Sept. 18, shining at magnitude -4.8 while just 26% lit. That’s the sweet spot, when its increasing angular size and decreasing crescent combine at their brightest, as seen from Earth (though its modeled visual brightness peaks a few days later, around Sept.22). After that, it becomes an increasingly dim crescent.

Seeing Venus as a crescent makes the geometry beautifully obvious. We are no longer looking across the solar system towards the brightly illuminated side of Venus. We are increasingly looking at the planet from behind, towards its night side, with sunlight catching only one edge.

It is almost the same idea as a crescent moon — except Venus is another world tens of millions of miles away. As it passes roughly between Earth and the sun on Oct. 24, it will be 0.27 AU away — equivalent to 25 million miles (40 million kilometers). At its farthest, Venus can be 162 million miles (261 million kilometers) from Earth.

The phases of Venus were historically important. When Galileo observed Venus through a telescope in the early 17th century, seeing it display a broad range of phases helped demolish the traditional Ptolemaic model in which Venus was supposed to orbit Earth in a way that could not produce the full sequence he observed.

Four centuries later, the same observation remains one of the simplest ways to understand our place in the solar system.

Venus becomes far more interesting when it stops looking its best through the naked eye and instead becomes a “wow” moment in a small telescope. As the “Evening Star” sinks lower into twilight, we’re not just seeing a crescent — we’re seeing a planet orbit the sun.

What’s happening and when to look

Venus remains an evening object throughout September, but it is rapidly becoming more challenging from mid-northern latitudes. Look very low towards the west-southwest shortly after sunset, where it should be obvious because practically nothing else in the twilight comes close to its brilliance.

Do not search for Venus with a telescope or binoculars while the sun is still above the horizon. Wait until sunset and make sure the sun has disappeared before pointing optical equipment anywhere near the western sky.

Venus will move through Virgo during the coming days before a particularly attractive conjunction on Sept. 14, when a 16%-lit waxing crescent moon will pass extremely close to a 29%-lit Venus. Two crescents together.

How and when I’m watching it

Venus is one of those objects I prefer to revisit several times rather than observe once. A single look shows a crescent, but observing every week reveals movement.

I’ll mostly use my small spotting scope in the front yard to look at Venus as a crescent this month, but if I’m short on time, I’ll use some 10×50 binoculars, which can also reveal the phase. The trick is not to expect surface detail — just a clean geometric shape.

Atmospheric turbulence near the horizon can make Venus wobble and shimmer, but its phase usually cuts through.

Stargazer’s corner: Sept. 4–10, 2026

With the moon now past last quarter, the early evening sky is finally free from bright moonlight. It’s an excellent opportunity to revisit the Milky Way, along with star clusters, nebulas and other deep-sky objects before autumn gradually takes over and its bright center slumps into the horizon. Before dawn, the waning crescent moon moves through Taurus, passing close to Mars on Sept. 6 in Gemini, while brilliant Venus continues to dominate the western twilight after sunset. The dazzling planet remains the unmistakable evening beacon, shining low above the west shortly after sunset. Saturn, meanwhile, continues to brighten in the east during the late evening, making this an increasingly good time to point binoculars or, better still, a small telescope toward the ringed planet.

Constellation of the week: Pisces

Pisces is easy to overlook. Its faint stars form two celestial fish joined by a long cord, creating a broad V-shape beneath the easy-to-find Great Square of Pegasus in the eastern evening sky after dark this month.

This week is a great time to find it because Neptune soon reaches opposition within Pisces, making the distant planet brighter than at any other time this year. Although Neptune needs binoculars or a telescope to spot it, learning the constellation

Pisces has been associated with mythology and water for thousands of years, but finding its subtle pattern also signals that the autumn constellations are beginning to take over the night sky.

Scientists are closer than ever before to understanding how stars forge the elements that comprise our planet, bodies and pretty much everything else around us — and they’re gaining a clearer picture of where star explosions fit into the story.

New research reported in two different papers looks at how stars forge elements as they explode and how these supernova explosions spread those elements — and other elements stars have forged during their lifetimes — throughout the cosmos.

Astronomers have been studying the bright supernova deaths of massive stars for centuries, but they still don’t quite understand how these explosions proceed.

The first paper looked at one way to investigate supernovas. It uses a radioactive element produced by these explosions called titanium-44, which lingers long after supernovas fade. Researchers have now collected experimental evidence that determines how much titanium-44 is created in a supernova, finding that these cosmic explosions produce 35% more of this element than expected.

With this knowledge in hand, scientists can now develop robust computer models of supernovas and compare these models with astronomical observations. This could bring them much closer to understanding how these explosions progress.

“It’s exciting to see just how far the field has come,” Christopher Cousins, a postdoctoral researcher in the University of Surrey’s Nuclear Physics Group, said in a statement. “A measurement like this would have been considered out of reach only a couple of decades ago, but it now gives us new insight into one of the biggest unanswered questions in astrophysics.”

The second paper honed in on a particular brand of stellar explosion called a Type I supernova. These occur when a dense stellar remnant called a neutron star drags material from a companion stellar body. The intense gravitational influence of the neutron star — a stellar corpse that has one to two times the mass of the sun crammed into a body about 12 miles (20 kilometers) wide — means that, when this stolen stellar matter hits their surfaces, a thermonuclear explosion is triggered.

These blasts forge heavy elements and release incredible amounts of energy, some in the form of X-ray bursts.

The authors of this paper, hailing from the Facility for Rare Isotope Beams (FRIB) in Michigan, studied the nuclear reaction that triggers X-ray bursts in greater detail than has been possible before.

This revealed the long-debated role of the so-called nickel-copper cycle, the temporary trapping of nuclear material during supernovas. Scientists previously didn’t know if material was trapped in the nickel-copper cycle during X-ray bursts.

This research reveals that this does happen, but only in small proportions. It gives scientists a clearer picture of how Type I supernovas proceed.

“Despite decades of research, we still don’t fully understand the nuclear reactions that power some of the universe’s most spectacular stellar explosions,” said Gavin Lotay of the University of Surrey.

“These two studies give us a much clearer picture of how these explosions happen, allowing us to compare our models more closely with astronomical observations and bringing us closer to understanding how the chemical elements are created and spread throughout the universe,” he added.

The two papers were published in the July edition of the journal Physical Review Letters.

About 160,000 light-years away lies one of our Milky Way’s little galactic neighbors: The Large Magellanic Cloud (LMC). And thanks to a new observing program, the Hubble Space Telescope has provided us with an intricate image of a nebula in the LMC. The surprising part? There’s a giant void at the center. Scientists call it a “superbubble.”

What is it?

What you’re seeing in this image is a nebula within the LMC known as LHA 120-N44, or simply N44. It’s located in the constellation of Dorado and, like a classic nebula, is the site of stars being born at a noticeably rapid rate.

But of course, what really can’t be missed is the huge hole at the center of N44’s dusty tendrils — this is the “superbubble,” and its dimensions are staggering. NASA says it’s about 210 by 140 light-years across — a truly unimaginable size, considering the distance between our sun and Pluto isn’t even a single light-year.

One light-year, the distance light travels in a year, is about 6 trillion miles (9.7 trillion kilometers).

Why is it noteworthy?

The superbubble is a bit of a mystery, but one theory of why it exists is that stars at the center of the bubble could have undergone supernova explosions or have released stellar winds that swept away gas in the nebula. This could have resulted in a “void,” as NASA calls it, surrounded by a gaseous shell. That would explain away the image we see pretty well, but there will likely be studies dedicated to refining that story.

Of note, in that shell around the superbubble, stars continue to form and show themselves as beautiful little specks across the watercolor-like landscape.

Something else interesting about this image is that N44 is what’s known as an “emission nebula,” meaning the gas you see has been energized by stars in the area. This enhances the luminescent quality of the portrait.

This is because the energization process, or ionization to be specific, generates ionized gas that ultimately must cool down. During that cooling, it goes from a higher energy state to a lower energy state and thus releases some energy. This energy loss causes N44 to glow brightly, creating the beautiful scene we see.

The reason scientists have used the Hubble Space Telescope to study N44 is this particular nebula offers good conditions to study star formation and evolution. As a matter of fact, Hubble managed to survey nearly half a million stars in and around the cluster, 30,000 of which are in the very early stages of their lives.

N44 has been a major topic of interest for quite some time. For instance, it made headlines in 2021 as well as in 2012 — both times due to Hubble’s eye yet again — and observations with the Chandra X-ray Observatory led to a 2011 paper that discusses supernova shock waves and other phenomena shaping the nebula and its cavity.

On Sept. 4, 1962, NASA’s Mariner 2 spacecraft performed the first-ever rocket maneuver in deep space as it did a quick mid-course correction on its way to Venus. It had launched just eight days earlier and needed to burn its engines to ensure that its trajectory would take it to Venus.

The midcourse maneuver was necessary because the Atlas-Agena rocket that launched Mariner 2 didn’t launch with enough accuracy to get the trajectory right in one shot. When it was about 1.5 million miles (2.4 million km) from Earth, it fired its engines to help steer it in the right direction.

The entire maneuver required five separate commands sent from mission control, telling the spacecraft to roll, pitch, turn and burn its motor. One hundred days later, Mariner 2 flew by Venus and became the first spacecraft to successfully fly by another planet.

Why it mattered

Tweaking a spacecraft’s course in deep space seems a bit routine these days (NASA’s newly launched Roman Space Telescope just performed such a feat this week), but in 1962 — when reaching another planet with a probe was still the stuff of fiction — it was far from a safe bet.

Mariner 2 launched in Aug. 27, 1962 on what would eventually be the first successful misson to another world. But as stated above, the launch wasn’t accurate enough to place Mariner 2 on a direct course for Venus.

That’s where the mid-course correction came in. The mission team designed a short engine burn that directed Mariner 2 to roll itself about 9.33 degrees, pitch its nose around 139.83 degrees so that it could turn its rocket engine to face forward, firing the engine, as Time Magazine recounted. The entire process took up to 36 minutes.

Without the mid-course correction, Mariner 2 would have missed Venus entirely. After launch, Mariner 2 was on a heading that would carry it only within 238,600 miles (384,000 kilometers) of the planet’s center, then speed on by, according to NASA’s official Mariner 2 report. After the course correction, Mariner 2 was on a path to fly by at a much closer distance of 21,607 miles (34,773 km).

Today, such mid-course corrections are a regular part of space mission planning, though they are still critical moments since a mission’s success can hinge on their results. In the decades since Mariner 2, space mission designers have achieved amazing feats in mid-course changes, including the now familar gravity assist flybys that allowed NASA to send Voyager 2 on its Grand Tour of Jupiter, Saturn, Uranus and Neptune. Many other missions have achieved such feats.

Even this week, on Sept. 3, 2026, the BepiColombo mission to Mercury performed its own mid-course event, with the mission’s Mercury Transfer Module releasing its two spacecraft (one each for Europe and Japan) to begin their arrival at Mercury. The event came eight years after launch and followed a series of maneuvers, including nine planetary flybys to reach the planet.

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