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The "Black Eye Galaxy" is captured in this new composite image from the Hubble Space Telescope and JWST. (Image credit: NASA, CSA, ESA, F. Belfiore (European Southern Observatory – Germany), J. Lee (Space Telescope Science Institute), A. Leroy (The Ohio State University), and D. Thilker (The Johns Hopkins University); Processing: Gladys Kober (NASA/Catholic University of America))

Sometimes, incredibly powerful space telescopes work together to accomplish amazing things. Recently, observations made by both the James Webb Space Telescope and Hubble were combined in a composite image that shows the incredible nature of the "Black Eye Galaxy," more formally known as Messier 64.

What is it?

The Black Eye Galaxy is a strange spiral galaxy located 17 million light-years from Earth, in the constellation Coma Berenices, a name that means "Berenice's Hair" in Latin.

Discovered in 1779, the Black Eye Galaxy is fairly isolated from other galaxies and is known for its hypnotizing "stare." This look is created by the galaxy's internal, swirling motion. However, unlike many other spiral galaxies, the gas in the outer reaches of this one rotates in the opposite direction to the gas and stars closer to its center, creating an especially unusual motion.

To capture this incredible composite view of the galaxy, astronomers combined near and mid-infrared wavelength observations made by JWST and ultraviolet, visible and near-infrared observations made by Hubble.

Why is it incredible?

As we look forward to observations from NASA's upcoming flagship space observer, the Nancy Grace Roman Space Telescope, this collaborative effort shows how such powerful instruments don't replace one another; rather, they bring different capabilities to the table and can complement each other.

And, while this new image is the result of a team effort of cutting edge-technology, the Black Eye Galaxy is also a favorite target for backyard astronomers because it can often be spotted in small telescopes.

The night sky is not an impenetrable “blanket of stars.” There is depth and detail that can be navigated and known, probed and plundered for rewards — and the best way to do all of that is with a manual telescope. Sure, you can get a motorized computerized “go-to” telescope and even one of the best smart telescopes that self-align and do all the work for you. Arguably, they also take much of the reward and leave you none the wiser. Can users of smart telescopes find Polaris, the North Star? Probably not. Do they know where the fabulous images of nebulae they produce actually come from? It’s doubtful.

Manual telescopes don’t find celestial objects for you — you find them yourself. However, it’s the only way to build sky literacy. Observing manually connects you to a long tradition of stargazers who learned the patterns of the sky by heart.

The learning curve can be steep, even with one of the best beginner telescopes. Knowing where to point a manual telescope is a challenge for beginners. With narrow fields of view, it’s easy to miss even bright targets unless you understand where objects are, how to navigate the sky and how to move your telescope.

All telescopes use lenses and/or mirrors to collect and focus light. There are several types of telescope — the main two being refractors and reflectors — as well as Dobsonians and catadioptrics (Schmidt-Cassegrains and Maksutov-Cassegrains). Let’s assume you already have one of the best telescopes. How does it move? There are two mount types — alt-azimuth and equatorial — each of which moves differently and has its own learning curve.

To lessen any confusion, here’s everything a beginner needs to know about observing the night sky with a manual telescope, and a glossary of telescope terms.

1. Understand the night sky

A reflector telescope is ideal for observing deep-sky objects. (Image credit: Getty)

The night sky is not static. Thinks of it as a celestial sphere surrounding a rotating globe; as Earth rotates, the stars appear to move across the sky — rising in the east and setting in the west, just like the sun — which is why objects drift out of a telescope’s field of view over time.

Since it’s not static, the celestial sphere requires two coordinate systems to help you understand this movement and find objects in the night sky:

Altitude and azimuth: typically shortened to Alt-Az, these describe where something is based on your position, with altitude meaning how far up in the sky an object is, and azimuth, where it is from left to right.

Right ascension and declination: typically shortened to RA/Dec, these are fixed coordinates that rotate with the celestial sphere, similar to longitude and latitude on Earth.

2. Manual telescope mounts and how to use them

This Skywatcher 200P is a powerful tool for surveying the night sky. (Image credit: Josh Dury)

A mount allows you to manually move and position a telescope. They come in two primary flavors: alt-azimuth (alt-az) and equatorial (EQ). However, pointing a telescope at the night sky and hoping you hit on something will not work because a telescope’s narrow field of view makes even very bright objects hard to see unless they’re precisely centered. Here’s why both mounts exist and how best to use them.

Alt-Azimuth mounts: Best for beginners and found on almost all low-cost models, these are simple (alt-az) mounts that move a scope up and down and left and right. Intuitive, easy to use and quick to set up, the constant adjustments required to track an object make it less accurate. That said, you could easily use an alt-az mount your entire life and never notice.

Locate a bright object, such as the moon, a planet or a bright star like Rigel, Vega or Arcturus, then use the finder scope or red-dot finder to roughly align the telescope.

Begin with your lowest magnification eyepiece‚ typically 25mm on a beginner’s model, for the widest field of view. Once your target is centered, you can switch to higher magnification, such as 10mm.

Move the telescope ever so slightly every few minutes to keep the object centred. If the object is drifting through the field of view from left to right, place it on the far left to keep it in view for as long as possible.

Use a manual telescope as a stargazing tool. (Image credit: Getty Images)

Equatorial mounts: A step-up choice, EQ mounts follow the sky’s natural motion. With one axis tilted to align with Polaris, the North Star (in the Northern Hemisphere), an EQ mount hence moves in sync with Earth’s rotation. While EQ mounts allow smoother tracking, particularly at high magnification, they are nevertheless complicated (and somewhat intimidating) to set up and typically include a counterweight, making them heavy and more expensive.

Understand that perfect polar alignment is not necessary for visual observing — getting as close as you can is fine.

In the Northern Hemisphere, point the telescope mount roughly north and set the mount’s tilt to match your location's latitude, using Polaris, the North Star, as a rough guide to true north.

Once aligned, track objects with a single slow-motion control, which keeps them centered for much longer and makes high-magnification viewing much easier.

3. Using a manual telescope for the first time

Once you've mastered viewing the night sky, astrophotography could be your next step. (Image credit: Getty Images)

Taking a telescope outside for the first time is as much about learning about the night sky as it is about your telescope. Assemble it indoors in daylight and test your finder scope or red dot finder on a distant object. Once it’s dark, place the lowest-power eyepiece (say, 25 mm) on your telescope, which will give you the widest field of view. Here is what — and what not — to do:

Standing still is how to get cold, so you’ll likely need to dress more warmly than you think.

Let your eyes adjust to the dark (which takes about 20 minutes), then preserve your night vision by using a red flashlight and avoiding smartphone screens (though some stargazing apps have a red light mode).

Be unambitious: Set aside a few hours to learn the absolute basics of using your finderscope, pointing the scope and centering and tracking objects.

Be patient, resisting the temptation to use too much magnification too quickly.

Don’t give up on faint objects, using the averted vision technique (looking to the side of an object) to help your eyes collect more light.

4. How to find objects with a manual telescope

You can minimise light pollution by seeking out countryside, fields and other less inhabited areas. (Image credit: Damian Peach)

You’re a stargazer interested in the night sky, not telescopes. Look at the night sky. Find a bright anchor star or constellation — maybe the moon, Saturn, Jupiter, Vega, Sirius, Orion’s Belt or the Big Dipper — then, using a simple star chart or astronomy app in night mode, trace a visual path to your target. Don’t feel bad about just stargazing for 15 minutes while you figure out where you are — that’s why you’re here. Know where you’re going to move the telescope before you touch it. Navigating from bright stars to fainter objects is how to be a successful manual observer. With practice, even the faint fuzzies will be within your reach; many manual observers with moderate experience can tell you exactly where, say, the Andromeda Galaxy is in the night sky, even though they can’t actually see it with their own eyes.

With just a few sessions, your skills will improve quickly, and you’ll recognize stars, constellations and patterns more easily — and every object you get in the crosshairs of your manual telescope will feel like your own discovery.

A quick telescope glossary

There are some terms every telescope user needs to know to appreciate how they work and why they’re designed as they are.

Term

Description

Aperture

The diameter of a telescope’s primary lens or mirror. A larger aperture means more light.

Eyepiece

The lens you look through; swap between them to change magnification.

Field of view

The visible area in the eyepiece; wider is better for finding objects.

Finder scope

The small, low-power scope mounted on the side of the telescope tube, which helps aim your telescope (also called a red dot finder).

Focal length

The distance light travels inside the telescope, which affects magnification.

Magnification

The mistaken obsession among beginners. Technically, it’s the focal length of the telescope divided by the focal length of the eyepiece. However, higher magnification isn’t always better, especially when you’re trying to locate and track an object. Start wide, then zoom in.

Slow-motion controls

Knobs or cables that let you finely adjust the telescope’s aim once you’ve roughly located an object.

Astronauts have long struggled with constipation in space. Now, scientists may finally understand why.

A new study of 52 astronauts who lived aboard the International Space Station (ISS) suggests that microgravity may slow the movement of food through the intestines, changing how gut bacteria break down nutrients. The findings could ultimately help researchers develop dietary strategies to keep astronauts' digestive systems running smoothly during future missions to the moon and Mars — while offering new clues about digestive problems here on Earth, according to a statement from the University of Copenhagen.

Constipation is a common problem among astronauts, but exactly what happens inside the gut during spaceflight has remained less clear. To investigate, researchers from the University of Copenhagen and NASA analyzed blood samples collected from astronauts before, during and after missions aboard the space station.

"We see changes in astronauts' blood samples that indicate that the gut bacteria begin to ferment protein to a greater extent than usual within weeks after the astronauts arrive in space, and this change continues until they are back on Earth," Giorgia La Barbera, co-lead author of the study and associate professor at the Department of Nutrition, Exercise and Sports, said in the statement.

The team used a technique called metabolomics to measure small molecules circulating in the blood, providing a biochemical snapshot of how the astronauts' bodies — and the microbes living inside them — were responding to spaceflight.

In total, the researchers analyzed 488 plasma samples from 52 astronauts who spent between two and nine months aboard the orbiting lab between 2006 and 2018. They identified changes in around 40 circulating compounds during spaceflight, including several metabolites produced when bacteria in the colon ferment proteins. Those compounds increased while the astronauts were in space, suggesting food was spending more time moving through their intestines, according to the statement.

Normally, bacteria in the colon ferment fiber and carbohydrates for energy. But when digestion slows, those carbohydrates can become depleted, causing microbes to break down more proteins instead and produce different metabolites that can enter the bloodstream. The changes appeared shortly after astronauts entered space and largely subsided within days of their return to Earth, providing biochemical evidence that digestion slows in space. Differences in diet, including caffeine, fish and fat intake, accounted for less than one-third of the metabolic changes, suggesting diet alone couldn't explain the effect.

"The lack of gravity in space probably causes food to move more slowly through the intestine, and this fits with the fact that we are seeing signs of increased protein fermentation," Henrik Roager, co-author of the study and also an associate professor at the Department of Nutrition, Exercise and Sports, said in the statement. "This may also help explain constipation in astronauts."

However, while the researchers did not directly measure how quickly food moved through the astronauts' digestive systems, the metabolic changes they observed suggest that it moved more slowly through the gut.

The findings could become increasingly important as astronauts spend months — or eventually years — away from Earth. Beyond the discomfort of constipation, increased protein fermentation can produce compounds such as ammonia and hydrogen sulfide, and the researchers say some of the metabolites associated with this process have been linked to other negative health effects.

One potential countermeasure may be relatively simple: more fiber. The team suggests increasing astronauts' intake of slowly fermented carbohydrates, which could give gut microbes more carbohydrates to consume and reduce their reliance on protein fermentation.

Understanding how microgravity affects digestion and gut bacteria could help keep astronauts healthy on increasingly long missions to the moon and Mars, while also offering new clues for treating digestive problems on Earth by revealing how slower movement through the gut changes microbial activity.

Similar studies of astronaut health in microgravity have also yielded insights for people back on Earth. Bone loss is one prominent example. Astronauts lose bone density much faster in microgravity than people typically do on Earth, and efforts to prevent that loss have helped scientists better understand osteoporosis and age-related bone loss. Spaceflight research has also offered insights into muscle loss, cardiovascular health and immune-system changes associated with aging and disease.

Their findings were published June 29 in the journal Nature Communications.

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