Whether you did or didn’t see this week’s Geminid meteor shower … you’ll enjoy these stunning images of the shower, from around the world. Thank you to all EarthSky community members who submitted – and are still submitting – photos. Visit EarthSky’s community photo page for more. And submit your photo here.

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Best Geminid meteors images

More Geminids images

More stunning images

More Geminid meteors

And last but not least …

Bottom line: See the best photos of the Geminid meteor shower of 2023 from our talented community of photographers.

The post Geminid meteor shower 2023: Cool photos! first appeared on EarthSky.

10 tips for watching the Geminids

2023’s Geminid meteor shower is expected to peak on December 14. This year, a thin waxing crescent moon won’t interfere viewing the meteors. And, the radiant point rises in mid-evening. So there will be darkness – on both the evenings of December 13 and 14 – from mid-evening until dawn. Read more about this year’s Geminid meteor shower.

Moon or no moon, the Geminid meteor shower is always worth a look. You never know when you’ll be surprised by a bright fireball. The radiant, which is near the star Castor in Gemini the Twins, rises in mid-evening for all of us around the globe. And then, it reaches nearly overhead around 2 a.m. (that’s why the shower is best then).

While it’s possible to see up to 120 meteors per hour on a dark night, when the radiant is overhead, it’s still exciting to see even just a handful of Geminid meteors. For your best chance to see the most Geminids, make sure you’re in a dark-sky location. Here are 10 tips to get the most out of the Geminids in 2023.

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1. The peak viewing time is around 2 a.m.

Geminid meteor numbers tend to intensify as evening deepens into late night, with the greatest number of Geminids likely falling an hour or two after midnight, when the meteor shower’s radiant point appears highest in the sky as seen from around the globe. That time holds true no matter your time zone. The waxing crescent moon will set soon after sunset on both December 13 and 14. So, you’ll be able to watch the Geminids in a moonless sky. Visit Sunrise Sunset Calendars to find the moonrise and moonset time for your specific location. Be sure to check the moonrise and moonset box.

2. Get away from city lights.

For optimum viewing, find a dark place to observe in the country.

3. Give yourself a wide-open view of the sky.

A farmer’s field? A stretch of country road? A campsite with a clear view in one or more directions? An open sky will increase your chances of seeing some meteors.

4. Watch for Geminids for an hour or more.

The 2023 Geminid meteor shower will be better if you let your eyes adapt to the dark. That can take as long as 20 minutes. Plus, the meteors tend to come in spurts, followed by lulls. Be patient! You’ll see some.

5. You don’t need to find the radiant point.

You don’t need to look in a single direction – or locate the Geminid’s radiant point – to have fun watching the shower. The meteors will appear all over the sky. The radiant point is interesting, though. If you track Geminid meteors backward on the sky’s dome, you’ll find them streaming from this point, within the constellation Gemini the Twins. Hence this shower’s name.

6. Pay attention to the moon.

The moon will be in a waxing crescent phase, the moon will not interfere with the Geminid meteors. However, if the moon was out – because you can look in any direction to spot Geminids – you can look at areas of the sky away from the moon. That’s because anything in the moon’s vicinity will likely be washed out by its bright light. Another tip for watching in moonlight: place yourself in a moon shadow. Observing from the shadow of a barn, or mountain, even a tree, can help you see more meteors.

7. Think about the Geminids’ parent object.

Most meteors in annual showers originate in comets. But the parent of the Geminid meteor shower is a mysterious body named 3200 Phaethon. This solar system object is termed an Apollo (near-Earth) asteroid, and it might be a dormant comet. This tidbit may not help you watch the shower, but it’s fun to discuss as you wait for the next meteor. Click here for more on weirdly comet-like 3200 Phaethon.

8. Bring along a buddy.

Both of you watch different parts of the sky. If you see one, shout “Meteor!” Let your eyes rove casually in all parts of the sky.

9. No special equipment needed.

You may be more comfortable with a reclining lawn chair, blankets, snacks and a hot drink. And leave your electronic devices in your pocket or the car. Even night mode is bright enough to ruin your night vision.

10. Enjoy nature.

As a wise man once said, meteor watching is a lot like fishing. You go outside. You hope you catch some!

Bottom line: The Geminids make up a rich and much-loved annual meteor shower that peaks in mid-December. Maximize your viewing time with these tips.

The post 10 tips for watching the Geminids in 2023 first appeared on EarthSky.

The Geminid meteor shower is peaking on the nights of December 13 and 14. Read more about 2023’s Geminid meteor shower.

Weirdly comet-like 3200 Phaethon

Most meteors in annual showers have comets as their sources. But not December’s Geminid meteors, whose source, known as 3200 Phaethon, is a strange hybrid of an asteroid and a comet. This “rock-comet” isn’t icy, like a comet is. But it brightens as it nears the sun, as comets do. And it’s been observed to have a tail when nearest the sun. Plus, it spawns the Geminid meteor shower. And so scientists have long puzzled over 3200 Phaethon. How can a rocky asteroid leave behind debris that sparks a meteor shower? Where does its tail come from?

In 2023, a couple of new studies provide insights on 3200 Phaethon, parent object of one of the year’s best meteor showers.

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New research from Lowell Observatory

The Planetary Science Journal published a new study about 3200 Phaethon in April 2023.

On December 13, 2023, Spaceweather.com quoted astronomer Karl Battams of the U.S. Naval Observatory – a co-author of the April study – as saying:

Our work has upended years of belief about 3200 Phaethon, the source of the Geminids. It’s not what we thought it was.

In other words, since its discovery in 1983, 3200 Phaethon has appeared to be a rocky asteroid. NASA’s STEREO spacecraft first observed its tail – which appears when 3200 Phaethon passes near the sun in its 524-day orbit – in 2009 and 2012.

But, according to the story in Spaceweather.com today (December 13), Qicheng Zhang at Lowell Observatory in Flagstaff was “never convinced.” Spaceweather.com explained:

For one thing, the Geminid debris stream is massive (1,013 kg or 2,233 pounds), while the tail of 3200 Phaethon is puny, providing less than 1% of the mass required to explain the Geminids.

‘The tail we see today could never supply enough dust to supply the Geminid meteor shower,’ says Zhang.

Zhang, Battams, and colleagues decided to take a closer look. Using coronagraphs on the Solar and Heliospheric Observatory (SOHO), they monitored Phaethon as it passed by the sun in 2022. Color filters on the spacecraft revealed no dust or rock. Instead, Phaethon’s tail is made of sodium gas.

And therein lies the twist. Meteor showers are made of meteoroids, not gas. Suddenly, the Geminids are a mystery again.

‘We’re back to square one,’ says Zhang. ‘Where do the Geminids come from?’

Source: Sodium Brightening of (3200) Phaethon near Perihelion

More new research on 3200 Phaethon

Could the answer come from more new research, published on November 2, 2023, by a team at the University of Helsinki? This new study appears in the journal Nature Astronomy.

This team compared an infrared spectrum of 3200 Phaethon – from NASA’s Spitzer space telescope – to infrared spectra of known meteorites. They found Phaethon’s spectrum showed olivine, carbonates, iron sulfides and oxide minerals. Those substances are also found in the composition of CY carbonaceous chondrite meteorites (a rare type of meteorites with only six samples available for study).

When CY meteorites are exposed to high temperatures, the carbonates in the meteorites produce carbon dioxide. That releases water vapor, and the sulfides release sulfur gas. Could that be what’s happening in 3200 Phaethon also? Is that why this object has a tail when nearest the sun?

Source: Thermal decomposition as the activity driver of near-Earth asteroid (3200) Phaethon

NASA also found sodium coming off 3200 Phaethon’s surface

Scientists with NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, first announced sodium fizzing from the asteroid’s surface in 2021. Their statement explained that this asteroid:

… brightens as it gets close to the sun. Comets typically behave like this: When they heat up, their icy surfaces vaporize, causing them to become more active and brighten as the venting gases and dust scatter more sunlight. But what is causing Phaethon to brighten if not vaporizing ices?

So it’s been thought for a few years that sodium could play a role in the formation of 3200 Phaethon’s tail.

Read more: Fizzing Sodium Could Explain Asteroid Phaethon’s Cometlike Activity

All that, and blue, too

By the way, the comet-like behavior of this asteroid isn’t the only unusual thing about it. For one thing, 3200 Phaethon has an odd color for an asteroid. Most asteroids are dull grey to red, depending on the type of material on their surface. 3200 Phaethon is blue. It’s not the only blue asteroid, but blue asteroids make up only a fraction of all known asteroids. And Phaethon isn’t just blue. It’s one of the bluest of similarly colored asteroids (or comets) in the solar system.

Here’s another odd feature of 3200 Phaethon. While comets tend to have more elliptical orbits, asteroid orbits are more circular. 3200 Phaethon’s orbit – which is now exceedingly well known – is highly elongated, reminiscent of some comets. Its orbit crosses the orbits of Mars, Earth, Venus and Mercury.

Plus, its orbit brings 3200 Phaethon closer to the sun than any other named asteroid (though some smaller, unnamed asteroids come even closer). At its closest point, Phaethon is only 13 million miles (20.9 million km) from the sun. That’s less than half of Mercury’s closest distance.

The name of this object – 3200 Phaethon – honors its relationship to the sun. In Greek mythology, Phaethon was the son of the sun god Helios.

A potentially hazardous asteroid

3200 Phaethon is classified as a potentially hazardous asteroid. But that doesn’t mean it’s a threat to Earth. It just means two things. First, 3200 Phaethon is big. The latest estimates (2021) suggest it’s 3.6 miles (5.8 km) wide. It’s big enough to cause significant regional damage if it were to strike Earth. Second, it makes periodic close approaches to Earth. But astronomers know of no upcoming strike by this object in the foreseeable future.

In 2017, 3200 Phaethon came closer to Earth than it will again until 2093. At its closest in 2017, it was still about 26 times the moon’s distance away.

Videos of 3200 Phaethon

Both amateur and professional astronomers watched 3200 Phaethon as carefully as they could in 2017. For example, Northolt Branch Observatories in London, England, created the animation below from images it captured in 2017.

Steven Bellavia also produced a video (below) of 3200 Phaethon in 2017. He commented then that he’d endured cloudy weather and subfreezing temperatures in order to capture the images.

The history of 3200 Phaethon

3200 Phaethon was the first asteroid discovered via spacecraft, on October 11, 1983. Astronomers Simon F. Green and John K. Davies noticed it while searching Infrared Astronomical Satellite data for moving objects. Charles T. Kowal confirmed it optically and said it was asteroid-like in appearance. The object received the provisional designation 1983 TB. Two years later, in 1985, using the convention for naming asteroids, astronomers assigned it its asteroid number and name: 3200 Phaethon.

Before 3200 Phaethon, scientists linked all known meteor showers to comets and not asteroids.

Thus, 3200 Phaethon surprised them from the beginning, because – while it looked like an asteroid – it appeared to be the source of the annual Geminid meteor shower. Astronomers began calling 3200 Phaethon a comet-asteroid hybrid, an asteroid that behaves like a comet. Later, they began using the term rock-comet.

What else will we learn about this object, as the years pass?

Bottom line: The Geminid meteor shower has a unique source – 3200 Phaethon – sometimes called a comet-asteroid hybrid, or a rock-comet. In November 2023, scientists found the composition of 3200 Phaethon matches a rare type of meteorite that releases gas when heated to temperatures like 3200 Phaethon experiences when it nears the sun. And in 2021, scientists suggested that some of this object’s comet-like behavior might stem from sodium fizzing from its surface.

Source: Thermal decomposition as the activity driver of near-Earth asteroid (3200) Phaethon

Via University of Helsinki, JPL and U.S. Naval Research Lab

The post Mysterious 3200 Phaethon – parent to the Geminids – revealed? first appeared on EarthSky.

What’s a red dwarf star?

Red dwarf stars are extremely common, at least in our Milky Way galaxy. They make up some 60 to 70% of all stars in our galactic home. In fact, the closest star to Earth, Proxima Centauri, is a red dwarf. And yet, you can’t see it with your eye alone – or any other red dwarf – because these stars are too dim. Red dwarf stars’ main characteristics are that they’re small, cool and live a long time. And, of course, they have a distinct red color.

The famous Hertzsprung-Russell diagram (or H-R diagram for short) lets you visualize where stars rank compared to other stars and throughout a star’s lifetime. Red dwarfs earn the classification of Type M. The red color is a sign of their low temperature. Cooler stars in the universe radiate light toward the red, long-wavelength end of the spectrum. Meanwhile, the hottest stars radiate toward the blue, shorter-wavelength end and shine blue or blue-white. In the same way, a poker put into a fire will start glowing with a dim red color. It will then glow orange, yellow and finally white as its temperature increases.

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Characteristics of a red dwarf star

Temperature: The surface temperature of red dwarf stars ranges from 2,000 to 3,500 degrees Kelvin (3100-5800 F or 1700-3200 C). Our sun is much hotter, at 5,500 degrees (9400 F or 5200 C), and it glows yellow as a result. A lower temperature also means lower luminosity: The largest, most luminous red dwarfs are only about 10% of the brightness of the sun. The smallest, dimmest ones are only around 0.075% our star’s brightness.

Size: The size of the smallest red dwarf stars is about 9% the radius of the sun. The largest red dwarf known, DH Tauri, has 1.26 times the radius of our sun. So, if the largest red dwarf can be bigger than our sun, then is our star called a dwarf star? And, in fact, astronomers do consider the sun a yellow dwarf star on the main sequence of the H-R diagram. While some ancient cultures worshipped the sun as the most powerful thing in the universe, in reality it’s a small and insignificant star. From just a few light-years away, extraterrestrial travelers might not even give it a second glance!

Lifespan: Red dwarfs are incredibly long-lived. They can live for tens of billions up to trillions of years. In other words many times the current age of the universe! But why is this?

The evolution of a red dwarf star

The key to understanding red dwarfs’ incredible longevity is their mass. Nuclear fusion is at the heart of every star, converting hydrogen into helium and producing heat, light and electromagnetic radiation. This nuclear fusion works at a rate governed by the mass of the star. The more massive the star, the greater the temperatures and pressures at its core, and the faster the fusion process proceeds. And vice versa. Red dwarfs typically have less than half of the mass of our sun. So, hydrogen is converted into helium at a slower rate. The end result is that red dwarfs evolve in slow motion compared to more massive stars.

However, red dwarfs, just like our sun, will one day exhaust their supply of hydrogen. In the case of the sun, this will happen when our star is around 8 to 10 billion years old; in other words, around 5 billion years from now. But because of the slow-motion fusion processes at the core of a red dwarf, this stage won’t arrive until the star is trillions of years old!

In the case of stars like our sun, the exhaustion of its hydrogen supply results in the star slowly inflating into a red giant star, many times its original diameter. But with red dwarfs, this doesn’t happen. Why? Once a star like our sun has exhausted its hydrogen, it starts to fuse helium, which triggers the inflation. However, red dwarfs don’t have enough mass to start fusing helium. Instead, the red dwarf stars bypass the red giant phase. Instead, they’ll slowly shrink and cool at the end their lives, becoming white dwarf stars. This is also our sun’s destiny after its red giant phase.

Exoplanets around red dwarfs

Astronomers have discovered planets orbiting red dwarf stars. What would it be like to live on one?

To an observer on a planet orbiting a red dwarf star, the star would appear to be much larger than the sun in our sky. But why, if red dwarfs are so much smaller than the sun? So far, the planets astronomers have discovered orbiting red dwarfs orbit much closer to their star. The red dwarf would therefore appear much larger than the sun does in our own sky.

The color of the red dwarf star would also be very different from our sun. Our sun emits most of its light in the yellow and green wavelengths of the spectrum, which is why it appears yellow to us. Red dwarf stars, on the other hand, emit most of their light in the red and infrared wavelengths. Thus, they would appear orange-red in the sky. The longer-wavelength light would also mean that the planet’s surface illumination would be far less. Everything on the planet would be dimmer and cast in red tones. Scientists think daytime on planets orbiting red dwarfs would never get any brighter than a sunset does on Earth.

Surveys have discovered that most of the planets orbiting red dwarfs are either comparable in size to Earth or are super-Earths. Scientists estimate that gas giant planets, like Jupiter, Uranus and Neptune, make up just one in 40 planets orbiting red dwarfs. In addition, computer simulations of red dwarf exoplanets indicate that at least 90% of them are at least 10% water by volume, meaning they may have global oceans.

Life on red dwarf exoplanets?

Because a red dwarf is much lower in temperature than stars like our sun, the red dwarf’s habitable zone is much closer to the star than in a planetary system like ours. Therefore, even though the planets we’ve found are closer to their red dwarf star, they might still be in the habitable zone.

However, before we get too excited about this possibility, there is one problem. Red dwarf stars are known for their violent solar flares. These flares can be up to a thousand times more powerful than the largest flares from our sun. Red-dwarf flares can emit intense radiation that can strip away the atmospheres of planets and make them uninhabitable. However, studies have shown that these flares may not be as destructive as previously thought. Flares tend to occur at high latitudes on the surface of a red dwarf, which means they may not strike planets that are orbiting closer to the star.

Solar flares on red dwarf stars are caused by magnetic activity. That’s the same thing that causes them on our sun. Red dwarf stars have very strong magnetic fields, which can become tangled and release huge amounts of energy in the form of a flare. Flares on red dwarf stars can last for hours or even days. And, they can release enough energy to power the entire Earth for centuries!

Is there a reasonable chance, therefore, that Earth-sized exoplanets orbiting red dwarfs, with their apparent abundance of water, might be hosts for life? Let’s look at one example of such a planetary system. This is a system that has astronomers and astrobiologists excited with its possibilities for life: the TRAPPIST-1 system.

The TRAPPIST-1 system

The TRAPPIST-1 system lies about 40 light-years from Earth. It’s home to seven Earth-sized planets, all orbiting the ultracool red dwarf. The planets are all quite close to their star, with orbital periods ranging from 1.5 to 19 Earth days.

Three of the TRAPPIST-1 planets are in the star’s habitable zone. This location makes them some of the most promising candidates for life outside our solar system that we’ve yet found.

When astronomers give names to exoplanets, they do so by designating each planet a letter, where “a” is the star itself, “b” is the planet orbiting closest to the star, “c” the next most distant, and so on. Observations with the James Webb Space Telescope have shown that:

• The surface temperature of TRAPPIST-1b is around 230 degrees Celsius (450 degrees Fahrenheit), making it too hot for liquid water to exist on its surface.
•  TRAPPIST-1c likely has a very thin atmosphere, or no atmosphere at all.

A chance for life near TRAPPIST-1?

However, intense and constant magneto-solar activity on TRAPPIST-1 is interfering with the Webb’s ability to obtain reliable spectra of the star. And from these spectra, scientists tease out the spectra of the planets’ atmospheres. So the spectra will probably need future observations and reanalysis. But, at the moment, it looks as if neither TRAPPIST-b or TRAPPIST-c is a likely candidate for life. Webb observations of the remaining planets, TRAPPIST-d to TRAPPIST-h, are still to come. Then, perhaps, we’ll have a profile of the whole system and understand a little more about red dwarfs, their activity and the effect they have on their planets.

Of course, all this does not mean that the TRAPPIST-1 system is typical of red dwarf planetary systems. It’s a mistake to draw general conclusions from what Webb discovered about its planets. We need to observe other planets orbiting these small, red stars. For example, astronomers have confirmed the existence of three exoplanets in the Gliese 581 system. This red dwarf is the oldest, least active M-type star currently known. Unfortunately, the three planets seem to orbit closer to their star than the inner edge of the habitable zone, so are likely too hot to support life.

The closest star to the sun, Proxima Centauri, is also a red dwarf. It has two confirmed Earth-sized exoplanets, one of which orbits in the habitable zone. However, little is known about this planet at the moment.

Understanding red dwarfs

Understanding red dwarf planetary systems is important, both for studying stellar evolution and in the hunt for extraterrestrial life. If it is true that exoplanets orbiting red dwarfs are never capable of supporting life, then at least 60% of the stars in our galaxy have lifeless systems. And that is significant.

Astronomers will continue to study these small, red, abundant stars in order to understand exactly how they behave and whether they’re capable of giving birth to exoplanets where we might find life. Red dwarfs are the obvious place to search for life-bearing planets because they’re cool, and therefore their habitable zones are close-in. That means that the length of a year for these planets – the time it takes to orbit their star – is much shorter. So, we can make repeated observations of them over a comparatively short time period as they transit across the face of the red dwarf.

Red dwarfs are an interesting area of study for astronomers and planetary science. They seem to be our best bet for finding planets with life. However, there is still a lot about them which we don’t understand. But with incredible tools such as the Webb and the upcoming planet-finding instruments, our knowledge of red dwarfs can only increase.

Bottom line: A red dwarf star is the smallest and coolest type of star known. They’re also extremely common, making up around 60 to 70% of the stars in the Milky Way.

The post What’s a red dwarf? Only the most abundant Milky Way star first appeared on EarthSky.

What to know before buying a telescope

Before you buy, ask yourself this question. Can you identify a few bright planets, and some bright stars and constellations? Buying a telescope is one thing; learning where and how to aim it is another. It’s fun to spend a year coming to know the stars and planets as they shift across Earth’s seasons. Do you need a telescope for that? Would binoculars be better?

It’s the wise beginner who spends a year with some simple star charts or a planisphere – and maybe a pair of binoculars – before investing in a telescope.

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First binoculars for stargazing

The pro for binoculars is their ease of use. Most of us have already held and pointed binoculars at distant objects. For the beginning stargazer, a pair of 7×35, 8×40 or 7×50 binoculars is probably your best choice.

The first number tells you the binoculars’ strength (magnification power) and the second the diameter of the objective lens, in millimeters. Binoculars can be used for stargazing up to a magnification of 10 without the support of a tripod. They won’t show you meaningful detail on the planets, but they’ll bring out some detail on the moon, let you glimpse some of Jupiter’s moons and enhance the colors and brightnesses of sky objects. Binoculars are particularly useful for deep-sky observing of star clusters, nebulae and galaxies.

The con for binoculars is that, because they work so well for beginning deep-sky observing, stargazers enjoy them most when they have regular access to darker skies. What’s more, binoculars use complicated optics based on internal prisms that work to provide an erect image. With time – maybe a few years – the prisms may lose their factory-set alignment. Plus, in humid climates both the prisms and the lenses may start developing mold.

Luckily, binoculars are a smaller financial investment than telescopes. A reasonable budget for beginners can range from about $100 and $200. Of course, you can spend more.

Read more: Top tips for binocular stargazing

Buying a beginner’s telescope

Once you know some bright stars and constellations, you’re ready to consider buying a telescope. Telescopes are either refractors (using lenses) or reflectors (using mirrors). Both are excellent.

If you want a refractor, consider a 3- to 4-inch (75- to 100-millimeter) long-tube achromatic refractor. Don’t confuse an achromatic refractor with an apochromatic. Those two seemingly inconspicuous letters can make a huge difference in cost.

If you want a reflector, consider a 6- to 8-inch (150- to 200-millimeter) with a Dobsonian mounting. This type of mounting was popularized by John Dobson in the 1960s. It’s easy to use and more portable than classical equatorial mounts. It is also cost-effective, giving you the best possible optical quality for the least money. Note, however, that Dobsonian mounts don’t use clock drives. To compensate for Earth’s spin, you have to “nudge” the telescope every few minutes along both axes to keep an object in view.

If your primary goal is astrophotography, you’ll need an equatorial mount and a clock drive. On the other hand, if you want a solid first telescope for learning the sky, a Dobsonian mount is for you. The budget for a beginner’s Dobsonian might range from $300 to $600. As always, you can spend more.

6 tips for 1st-telescope buyers

1. A beginner should be concerned more with aperture (tube diameter) than with magnifying power. The primary purpose of an astronomical telescope is to collect light; its magnifying power is a by-product. For example, a 6-inch (150-mm) telescope has twice the diameter of a 3-inch (75-mm) unit, meaning that its optical surface will be four times larger. In turn, this tells us that the 6-inch instrument will gather four times as much light as the 3-inch, making it four times more powerful. Given equal optical quality, a larger aperture is preferable, if the budget allows.

2. Consider who will use the telescope, and how. Telescopes are big and bulky, requiring setup each time. Purchase a telescope that is manageable for the person who will be using it. Children and older stargazers, in particular, might get more use out of smaller, lighter instruments.

3. Spend a year just observing, and not taking pictures. Learning to see fine detail on planets and the moon, and in the vast array of objects in the deep sky, is an art. With practice, your eyes will learn to see. Budding astronomers will benefit from putting lots of time at the eyepiece. So, a first telescope should be optimized for visual astronomy and not photography.

4. Consider what else you need for an observing session. Many stargazers bring along lawn chairs, perhaps a small table to spread out your charts, a thermos of coffee, sandwiches. And, of course, you will need a red flashlight in order to read your charts without ruining your night vision.

5. Keep your expectations reasonable. A planet will not appear through your eyepiece as it looks on your wall poster! Also, forget about colorful nebulae. Light collected by a telescope is seen differently by cameras versus the human eye. All of that said, if you patiently train your eye to see – and allow yourself some visits to dark-sky locations – you might find yourself falling in love with the silence, the night air, and the wonder of peering upward, through a telescope, at the universe’s marvels.

6. Connect with other amateur astronomers. Get in touch with your local astronomy club. Take a peek through the eyepiece of every telescope you encounter. Speak to the owners and ask them about the pros and cons. They’ll love to tell you about it. In this way, you can become familiar ahead of time with the basic setup and operation of an astronomical instrument. To find a group near you worldwide, visit this list at Skyandtelescope.com. For the U.S., visit this list from NASA.

Good luck and have fun!

Bottom line: Binoculars are excellent for learning the sky, providing good views of the solar system and deep sky objects for beginners. When you finally decide to buy your first-ever telescope, keep it simple! A telescope that is easy to set up, use and repair is key to a solid beginning in amateur astronomy.

Read more: Top tips for binocular stargazing

The post Thinking of buying a telescope? Read this 1st first appeared on EarthSky.

Mars sometimes appears bright in our sky and sometimes appears faint. In early 2023, Mars appeared as bright as the sky’s brightest stars. Mars had disappeared from our view in October 2023, … it was close to the sun. And it won’t be back until next year when it will appear in the morning sky.

Mars in 2023

Opposition for Mars last fell on December 8, 2022. That’s when our planet Earth last flew between Mars and the sun. As 2023 began, Mars was still bright. By September 2023 Mars had faded and was difficult to catch in the evening twilight. Mars will reach opposition again in January 2025.
How to see Mars in the sky: In December 2023, Mars is too close to the sun to see. It reached solar conjunction at 6 UTC on November 18.
Constellations in December 2023: If we could see Mars, it would be crossing in front of the constellation Scorpius this month. And then, Mars moves in front of the constellation Ophiuchus and Sagittarius by the end of the month.
Note: Mars reaches opposition only about every 26 months, or about every two Earth-years. So Mars alternates between appearing bright and faint in our sky. It was bright in late 2022 and early 2023. But by September 2023, Mars faded dramatically in brightness and disappeared in the sunset glare in October 2023. It’ll pass behind the sun on November 18. It’ll come back into view, in the east before sunrise, in early 2024.

Sometimes, Mars is faint

Mars was in our evening sky for much of 2021. But, around October, the red planet disappeared from our sky for a time. Its superior conjunction – when it was most directly behind the sun as seen from Earth – was October 8, 2021. Then, some weeks afterwards – as both Earth and Mars moved in their respective orbits around the sun – Mars returned to our sky as a faint red dot in the east before sunrise. To be sure, it remained inconspicuous throughout the early months of 2022.

Sometimes, Mars is bright

Mars steadily brightened in the first half of 2022, first as a morning object. But later, during the second half of 2022, Mars shone as a bright red ruby in the evening sky. Ultimately, it reached opposition – when Earth flew between Mars and the sun – on December 8, 2022.

Indeed, Mars’ dramatic swings in brightness (and its red color) are why the early stargazers named Mars for their God of War.

Sometimes the war god rests. And sometimes he grows fierce! In fact, these changes are part of the reason Mars is so fascinating to watch in the night sky.

Want to follow Mars? Bookmark EarthSky’s monthly night sky guide.

Mars isn’t very big

To understand why Mars varies so much in brightness in Earth’s sky, first realize that Mars isn’t a very big world. Indeed, it’s only 4,219 miles (6,790 km) in diameter, making it only slightly more than half Earth’s size (7,922 miles or 12,750 km in diameter).

On the other hand, consider Mars in contrast to Jupiter, the biggest planet in our solar system. Jupiter is 86,881 miles (140,000 km) in diameter. As an illustration, more than 20 planets the size of Mars could be lined up side by side in front of Jupiter. Basically, Jupiter always looks bright, because it’s so big.

Not so for little Mars, however. Rather, its extremes in brightness have to do with its nearness (or lack of nearness) to Earth.

Future Martian oppositions

So, when is the next opposition of Mars? The next time Mars will appear at its brightest for that two-year period in our sky? You guessed it. In January 2025! Check out the chart on this page that lists all oppositions of Mars from 1995 to 2037.

Seeing red

Mars appears as a reddish light in the sky and, therefore, is often called the Red Planet. Other obvious red dots in the sky are reddish-orange Aldebaran and the famous red supergiant Betelgeuse. So, it is fun to compare Mars’ color and intensity of red with that of Aldebaran or Betelgeuse.

And then there is red Antares. Antares is Greek for rival of Ares, meaning rival of Mars. Antares is sometimes said to be the anti-Mars due to its competing red color. For a few months every couple of years Mars is much brighter than Antares. Also, every couple of years Mars passes near Antares, as if taunting the star. Mars moves rapidly through the heavens and Antares is fixed to the starry firmament.

What makes them red?

Surface temperature is what determines the colors of the stars. The hottest stars are blue and the coolest stars are red. In fact, from hottest to coolest, the colors of stars range from blue, white, yellow, orange and red. And while the colors of stars might be hard to detect, some stars – like Aldebaran, Antares and Betelgeuse – are noticeably colorful.

On the other hand, Mars appears red for a different reason. It’s red because of iron oxide in the dust that covers this desert world. Iron oxide gives rust and blood its red color. Rovers on Mars sampled the Martian dust and determined it contains three colors: reds, browns and oranges. So those three colors are what you may see when you gaze upon Mars.

Do you see red when you look at Mars, Aldebaran, Antares and Betelgeuse? Are they the same color? Do you see any other colors of stars?

Bottom line: Mars is no longer visible in our night sky. It is too close to the sun to see for the rest of 2023. It’ll return in January 2024 as a light in our morning sky.

Moon and Mars! Fav photos of December 7 occultation

Photos of bright Mars in 2018, from the EarthSky community

Photos of bright Mars in 2020, from the EarthSky community

The post Mars in 2023: Mars is too close to the sun to see now first appeared on EarthSky.

When is the next meteor shower? Click here for EarthSky’s meteor shower guide

It’s meteor time! There are several meteor showers starting in December and around the December solstice. How can you optimize your chances for seeing the most meteors? Follow the tips below. See EarthSky’s meteor guide for upcoming meteor showers.

1. Know the peak time

Meteor showers generally happen over many days as Earth encounters a wide stream of icy particles in space. These particles are debris left behind by a comet. The peak is a point in time when Earth is expected to encounter the greatest number of comet particles. To find the peak dates of meteor showers, try EarthSky’s meteor guide.

And here’s the catch … the peak of the shower comes at the same time for all of us on Earth. Meanwhile, our clocks are saying different times. You’ll often need to adjust from UTC to your local time.

The predictions are not always right on the money, by the way. And remember … it’s possible to see nice meteor displays in the hours – even days – before or after the predicted peak.

Just remember, meteor showers are part of nature. They often defy prediction.

2. Location, location, location

We can’t say this strongly enough. You need a dark place to observe in the country. Visit EarthSky’s Best Places to Stargaze.

And … you need a wide-open view of the sky. A farmer’s field? A stretch of country road? A campsite with a clear view in one or more directions? An open sky will increase your chances of seeing some meteors.

3. Oh no! The moon is out

In meteor showers, a bright moon is not your friend. Nothing dampens the display of a meteor shower more effectively than a bright moon.

If the moon is out, look at areas of the sky away from the moon. Anything in the moon’s vicinity – including meteors – will likely be washed out by its bright light. Another tip for watching in moonlight: place some object between yourself and the moon. Observing from the shadow of a barn, or vehicle, even a tree, can help you see more meteors.

4. Know the expected rate

Here we touch on a topic that sometimes leads to some disappointment, especially among novice meteor-watchers: the rate.

Tables of meteor showers almost always list what is known as the zenithal hourly rate (ZHR) for each shower.

The ZHR is the number of meteors you’ll see if you’re watching in a very dark sky, with the radiant overhead, when the shower is at its peak. In other words, the ZHR represents the number of meteors you might see per hour given the very best observing conditions during the shower’s maximum.

If the peak occurs when it’s still daylight at your location, if most of the meteors are predominantly faint, if a bright moon is out, or if you’re located in a light-polluted area, the total number of meteors you see will be considerably reduced.

5. Don’t worry too much about radiant points

You don’t need to stare all night in a single direction – or even locate the radiant point – to have fun watching the shower. The meteors will appear all over the sky.

But … although you can see meteors shoot up from the horizon before a shower’s radiant rises, you’ll see more meteors after it rises. And you’ll see the most when the radiant is highest in the sky. So find out the radiant point’s rising time. It can help you pinpoint the best time of night to watch the shower.

And … the radiant point is interesting. If you track meteors backward on the sky’s dome, you’ll find them streaming from their radiant point, a single point within a given constellation. Hence the meteor shower’s name.

6. Watch for an hour or more

Meteor showers will be better if you let your eyes adapt to the dark. That can take as long as 20 minutes. Plus, the meteors tend to come in spurts, followed by lulls. Be patient! You’ll see some.

7. Notice the meteors’ speeds and colors

The Leonid meteors seem to zip across the sky, while the Taurids are slow enough everyone can see them when someone yells “Meteor!” Also, some meteor showers, such as the Perseids, can be colorful. Another beloved shower, the Geminids, tend to be bright and white.

8. Watch for meteor trains

A meteor train is a persistent glow in the air left by some meteors after they have faded from view. Trains are from luminous ionized matter left in the wake of this incoming space debris.

9. Bring a blanket, a buddy, a hot drink and a lawn chair

A reclining lawn chair helps you lie back in comfort for an hour or more of meteor-watching.

If several of you are watching, take different parts of the sky. If you see one, shout “Meteor!” Dress warmly; the nights can be cool or cold, even during the spring and summer months. You’ll probably appreciate that blanket and warm drink in the wee hours of the morning. Also, leave your laptops and tablets home; even using the nighttime dark mode will ruin your night vision. And this will be tough on some people: leave your cell phone in your pocket or the car. It can also ruin your night vision.

10. Enjoy nature

Relax and enjoy the night sky. Not every meteor shower is a winner. Sometimes, you may come away from a shower seeing only one meteor. But if that one meteor is bright, and takes a slow path across a starry night sky … it’ll be worth it.

To be successful at observing any meteor shower, you need to get into a kind of zen state, waiting and expecting the meteors to come to you, if you place yourself in a good position (country location, wide open sky) to see them.

Or forget the zen state, and let yourself be guided by this old meteor watcher’s motto:

You might see a lot or you might not see many, but if you stay in the house, you won’t see any.

Photos of meteors from EarthSky’s community

Post your own photos at EarthSky Community Photos

Bottom line: Meteor showers are unpredictable but always a fun and relaxing time. Maximize your viewing time with these tips.

The post Winter meteor showers are here: Top 10 tips for watching first appeared on EarthSky.