Page 182 | Astronomy Magazine (2024)

I’ve always held the opinion that a backyard astronomer should never go outside without an organized list of objects to observe. Whether designed for a single evening or as part of a goal-oriented observing program, having a plan helps you avoid night after night of aimless searching, which could diminish your interest in the hobby. I offered ideas for one-night observing lists in my February 2020 column, “February’s Finest Sights.” But this time around, we’ll look at some extensive compilations of deep-sky objects that can keep you engaged for nights on end.

Perhaps the best known deep-sky list is the Messier Catalog. And while it can serve as a single night list (if you’re adventurous enough to tackle a Messier marathon), its 110 entries are better subdivided into a series of smaller lists that can be spaced out over the course of a year. The annual edition of the Observer’s Handbook, published by the Royal Astronomical Society of Canada, includes a Messier Catalog list broken down by season. This month, the winter Messier objects are still visible after sunset. So, if you put four to six targets on each individual list (my recommended number for a single-evening session), you can view them all over the course of several nights.

However, the Messier Catalog isn’t the only game in town. The Observer’s Handbook has a matching 110-entry list of the finest NGC objects, again organized by season. Experienced amateur astronomers who own medium- to large-aperture scopes also will want to tackle the book’s Deep-Sky Challenge, a 45-entry list arranged in order of increasing right ascension, put together by Alan Dyer and Astronomy contributor Alister Ling.

Want more? The Observer’s Handbook also includes Deep-Sky Gems, a seasonal listing of 154 nebulae, clusters, and galaxies compiled by noted comet hunter David Levy. Finally, if you’re a deep-sky specialist, you’ll also find lists devoted to double and multiple stars, carbon stars, open and globular star clusters, and galaxies. The Observer’s Handbook is an essential guide for amateur astronomers, filled with observing hints, a monthly sky calendar, and a wealth of data on solar system and deep-space objects. (The 2021 edition is available at MyScienceShop.com.)

For even more deep-sky lists, go to the website www.astroleague.com, scroll down to the menu on the left-hand side, and click on “Observing Programs.” This page describes the Astronomical League’s observing programs (featured in my March 2015 column, “Astronomical Game Plans”). From there, you can access an alphabetical list of the Astronomical League’s 70-plus observing programs. Pick one that interests you and download the list. You don’t have to be an Astronomical League member to do so, but if you are a member and complete a program, you’re also eligible for a certificate and award pin.

Rich Kupfer of Boynton Beach, Florida, has created a deep-sky list of his own entitled “The Elite 800 (A Deep-Sky Catalogue for the Discerning Visual Observer).” Designed for the backyard astronomer equipped with a moderate telescope, it was compiled from thousands of observations Kupfer made over the course of 40 years. Arranged alphabetically by constellation, it lists some of the most notable multiple stars, variable stars, carbon stars, asterisms, and deep-sky objects. The entries for some constellations are short enough to place on a single-evening list. Others are rather extensive (Virgo’s list covers nine pages!) and will need to be broken into multiple lists. Although “The Elite 800” was compiled with a 14-inch scope, many of Kupfer’s entries are within reach of smaller-aperture instruments. Get your free PDF copy by contacting Kupfer at rkupfer3@comcast.net.

Questions, comments, or suggestions? Email me at gchaple@hotmail.com. Next month: Which constellation has the most stars of spectral class K9?

Last month, we visited the constellation Lepus, found south of Orion. This month, we will turn our attention toward the area north of Auriga. This region appears nearly starless even under dark rural skies. Ancient stargazers also thought this section of the sky was empty, so never concocted a constellation there. It wasn’t until 1612 that the Dutch-Flemish astronomer Petrus Plancius drew a pattern among those faint points: A giraffe, which he called Camelopardalis.

That’s right — Camelopardalis is not a camel, despite the misleading name. Translated, the Latin term Camelopardalis roughly means “camel leopard,” which comes from the way ancient Greeks described giraffes. So, even though they didn’t conceive the constellation, in one sense they did give it a name.

While Camelopardalis may not look like much to the unaided eye, it does hold some buried treasure for binocular users. Are you up for a hunt?

The brightest star in the celestial giraffe is 4th-magnitude Beta (β) Camelopardalis, found about 15° north of Capella (Alpha [α] Aurigae). Beta Cam is a type G1 yellow supergiant, slightly hotter than our Sun and over six times as massive. It lies 870 light-years from our solar system, roughly the same distance as Rigel (Beta [β] Orionis). Through binoculars, it displays a subtle yellowish tint.

While you are enjoying Beta Cam, take notice of a fainter pair of stars just a degree to the south. Those are 11 and 12 Camelopardalis. They appear just 3′ apart on the sky. Through binoculars, 5th-magnitude 11 Cam shows a delicate blue-white hue, while 6th-magnitude 12 Cam appears orangish. But their numerical affiliation is purely circ*mstantial, I’m afraid. Astronomers estimate that 11 Cam is 710 light-years from Earth, while 12 Cam is about 10 light-years closer. Although they are relatively near each other in space, they do not form a binary star system.

Given the sparseness of the area, you would hardly expect to find an open star cluster here. And yet there is: Collinder 464 is a late entry in Per Collinder’s 1931 catalog of 471 open clusters. Several clusters Collinder listed were previously included in the Messier and NGC listings, but others were not, including number 464. To find it for yourself, return to Alpha Cam and continue another 8.5° toward Polaris. Keep your eyes peeled for a dozen faint stars loosely gathered across an area measuring about 1° by 2°. The 5th-magnitude star SAO 5455 lies near the center of the cluster. By using a little imagination and borrowing some non-cluster stars in the immediate area, I see Collinder 464 forming the profile of a small dog. In my mind, the dog is facing west, with its legs stretching to the south and tail standing at attention to the east. The stars that mark the tip of the dog’s nose, ear, and tail look very slightly orangish, while the others appear white. Years ago, I nicknamed the cluster “Amy” after my toy poodle, who loyally accompanied me on many a night viewing the sky.

Our final stop this month is spiral galaxy NGC 2403, one of the brightest galaxies north of the celestial equator that Charles Messier missed. Instead, it was discovered by William Herschel in 1788. Although NGC 2403 lies within the borders of Camelopardalis, it is most easily found by looking about 8° northwest of 3rd-magnitude Muscida (Omicron [ο] Ursae Majoris), the star at the tip of the Great Bear’s nose. Look for its soft 9th-magnitude glow just north of a rectangle of 8th-magnitude stars. Through my 10×50 binoculars, NGC 2403 displays a dim oval disk skewed northwest-southeast. It lies approximately 10 million light-years away — about the same distance as M81 and M82, which are 14° to its east. Researchers believe that NGC 2403 is likely an outlying member of that galactic group.

We will explore the western portion of Camelopardalis later this fall. But for now, if you have any questions, comments, or suggested targets, I would enjoy hearing from you. Contact me through my website, philharrington.net. Until next month, remember that two eyes are better than one.

The morning of August 20, 2014 was a quiet one in Earth’s ionosphere. The solar wind was calm and slack, and the orientation of the Sun’s magnetic field was stable, not conducive to producing much space weather.

But then, hundreds of miles above the North Pole, the ionosphere suddenly whipped itself into a fury, spawning a massive space hurricane some 600 miles (1,000 kilometers) wide — a cyclone of plasma swirling above Earth for eight hours.

The phenomenon was captured in real-time by U.S. military weather satellites. But it was only recently uncovered in archival data by a team led by researchers at Shandong University in China.

“Until now, it was uncertain that space plasma hurricanes even existed, so to prove this with such a striking observation is incredible,” said co-author Mike Lockwood of the University of Reading in a press release.

More than a metaphor

The moniker “space hurricane” isn’t just a catchy nickname — the physics of how it formed are actually analogous to how “normal” hurricanes gather and focus energy in the lower atmosphere. Like their atmospheric counterparts, this space storm was instigated by an area of low pressure that gave rise to rapid convection.

On Earth, that convective process occurs from below: heat from warm ocean waters drives evaporation and rising air, dumping energy into the atmosphere that gets focused by inrushing wind.

In space, though, that convective energy comes from above — thanks to the magnetic fields of the Earth and Sun interacting and shearing across one another.

The Sun’s magnetic field has a wavy pattern as it stretches out into the solar system, meaning it can be aligned northward or southward depending on where Earth sits in it. On that August day in 2014, the region of the Sun’s magnetic field around Earth happened to be aligned northward. That means it doesn’t neatly connect to Earth’s magnetic field, which is also aligned northward — the field lines tend to repel each other, typically leading to calm space weather conditions. But these conditions sometimes give rise to a spot of aurora near the poles, where electrons rain downward and electric current flows up, just like the convection at the heart of a hurricane.

This caused the surrounding plasma to begin flowing around the central spot of convection, forming “rain bands” of electrons that produced spiral auroral arms around a stable eye. At the core of the system was a corkscrew-shaped magnetic field that funneled magnetic energy from space into Earth’s ionosphere — and it lasted eight hours before dissipating.

Universal phenomenon

Though space hurricanes don’t have the same kind of deadly impact that atmospheric cousins can, the influx of energetic particles such storms bring to the ionosphere could interfere with satellites, even affecting their orbits by creating more drag on them.

And because this particular storm popped up during a relatively quiet period of geomagnetic activity, the researchers say space hurricanes may be even more common than we thought. “Plasma and magnetic fields in the atmosphere of planets exist throughout the universe, so the findings suggest space hurricanes should be a widespread phenomena,” said Lockwood.

At around 7 P.M. JST on the evening of March 18, Japanese amateur astronomer Yuji Nakamura spotted something strange: A new point of light in the familiar constellation Cassiopeia the Queen.

Researchers at Kyoto University quickly followed up using the 3.8-meter Seimei Telescope atop Mt. Chikurinji in Japan. They obtained a spectrum of the new object, hoping to determine its nature based on clues hiding in its light.

They discovered that the object, which is cataloged as PNV J23244760+6111140, is a classical nova: An outburst from a white dwarf that’s stealing matter from its nearby companion star.

The new nova is growing brighter, too. At the time of its discovery (March 18), it was shining at magnitude 9.6. But within a matter of hours, it had brightened to magnitude 9.1. Images taken earlier today (March 19), show it has brightened yet again, reaching magnitude 7.8. That’s bright enough to spot it with binoculars from your backyard.

The nova sits about 5.9° northwest of Caph, which marks the western end of the W asterism. Alternatively, you can find the nova about 30′ east-southeast of NGC 7635, also known as the Bubble Nebula, or 10′ northwest of the magnitude 6.6 field star, HIP 115691.

For those with go-to instruments, you can slew directly to PNV J23244760+6111140 by inputting the following coordinates:

Right Ascension: 23h 24m 47.60s
Declination: +61° 11′ 14.0″

It’s hard to tell how long PNV J23244760+6111140 will be visible or how bright it will ultimately get. And that means you should track it down as soon as possible. So, turn your binoculars or telescope to Cassiopeia this weekend and stay tuned as astronomers following this exciting event!

Friday, March 19
At this time of year, stepping outside after dark and looking high overhead in the northwest will net you the bright star Capella in the constellation Auriga the Charioteer. Capella is a yellow-white star (actually a binary, but its components are challenging to separate) whose name means “she-goat.” Just south of the star is a small, three-star asterism called The Kids; one of these stars is Epsilon (ϵ) Aurigae.

Auriga houses several deep-sky gems, including three Messier open clusters (for those still working on their Messier marathons — more on that tomorrow!). M38 is a faint cluster that lies about halfway between Al Kab and Bogardus (Iota [ι] and Theta [θ] Aurigae); binoculars may pick it up, and a small scope certainly will. M36 is just over 2° northeast of Chi (χ) Aurigae. Smaller than M38, its light is more condensed and may be easier to see. Finally, you’ll find M37 nearly 5° south-southwest of Theta, just one binocular field east of M36. The brightest stars in this cluster are around magnitude 9, so its light is a bit misty but discernible from the background if you take your time.

Sunrise: 7:05 A.M.
Sunset: 7:12 P.M.
Moonrise: 10:19 A.M.
Moonset: 12:25 A.M.
Moon Phase: Waxing crescent (33%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 12 P.M. local time from the same location.

Saturday, March 20
The vernal equinox occurs at 5:37 A.M. EDT this morning. On the equinox, the Sun sits exactly above Earth’s equator; this date also marks the beginning of spring in the Northern Hemisphere.

If you weren’t able to get in on the Messier marathon excitement last weekend, don’t worry — this weekend is your next best chance to run the race. The waxing Moon will present slightly more of a challenge when finding fainter objects early on, but the early morning hours of the 21st will be Moon-free and darker as you near the finish line.

And if you don’t want to search out Messier’s full catalog yourself, let the staff at Lowell Observatory in Flagstaff, Arizona, do it for you! The observatory is hosting a virtual star party beginning at 6:45 P.M. PST tonight and running overnight, ending just before sunrise in Flagstaff at 6:15 A.M. PST on Sunday. The event, which will be recorded in Lowell’s Giovale Open Deck Observatory, will be livestreamed simultaneously on YouTube and Twitch, or you can watch it below.

Sunrise: 7:03 A.M.

Sunset: 7:13 P.M.
Moonrise: 10:57 A.M.
Moonset: 1:25 A.M.
Moon Phase: Waxing crescent (42%)

Sunday, March 21
First Quarter Moon occurs at 10:40 A.M. EDT.

Although our satellite is quickly growing brighter night by night and washing out deep-sky objects, bright stars remain easy to spot and fun to observe. One such star is Alula Australis — a rapidly moving binary star system in Ursa Major the Great Bear. Also known as Xi (ξ) Ursae Majoris, the pair was first identified as a physically related duo (i.e., not just a visual pair) by William Herschel in 1780. (Stay tuned — Herschel will also feature later this week.) Nearly 50 years later, Xi became the first binary to have its orbit determined, thanks to French astronomer Felix Savary.

Xi’s orbital period is about 60 years. That may seem long, but it still means the pair moves noticeably over the years. Amateur observers have long delighted in drawing the pair, then returning years later to see what change has wrought.

First, find Xi by looking 1.3° south of Alula Borealis (Nu [ν] Ursae Majoris), often drawn as the Bear’s back foot. Through a telescope, you can split magnitude 3.8 Xi into a magnitude 4.3 primary and a magnitude 4.8 companion. Once you’ve found them, take a photo or make a sketch of the stars’ locations. Keep this safe — it will be your roadmap when you next return to see how much they’ve moved.

Sunrise: 7:01 A.M.
Sunset: 7:14 P.M.
Moonrise: 11:41 AM
Moonset: 2:22 A.M.
Moon Phase: Waxing gibbous (51%)

Monday, March 22
Mars passes 7° north of Aldebaran at 8 P.M. EDT. Don’t confuse the magnitude 1 planet for the red giant star, which is slightly fainter at magnitude 0.8 and much closer to the Hyades open star cluster sprinkled across the Bull’s nose.

To their west is the Pleiades (M45) open cluster, which can look a little like a tiny dipper on the sky — in this case, not to be confused with the Little Dipper asterism, which is much larger and circles the North Celestial Pole, with the North Star Polaris at the end of its handle. The Pleiades is a gorgeous naked-eye sight, with at least six or seven bright stars visible to most observers; eagle-eyed individuals may count a few more. This famous cluster is also emblazoned on the back of every Subaru vehicle, as the brand name is also the cluster’s Japanese name.

Sunrise: 7:00 A.M.
Sunset: 7:15 P.M.
Moonrise: 12:32 P.M.
Moonset: 3:18 A.M.
Moon Phase: Waxing gibbous (61%)

Tuesday, March 23
Asterisms are unofficial patterns of stars not recognized as one of the 88 official constellations. One of the most famous is the Summer Triangle — but did you know there’s a Spring Triangle, too?

The Spring Triangle comprises magnitude –0.04 Arcturus (Alpha [α] Boötis) in Boötes, magnitude 1 Spica in Virgo (Alpha Virginis), and magnitude 2.1 Denebola (Beta [β] Leonis) in Leo the Lion. Although the Triangle is visible all night during the spring in the Northern Hemisphere, the season is still young and Spica — the last of the three to rise — currently clears the horizon shortly before 11 P.M. local time. Once you’ve found this asterism, however, keep returning to it once a week or so to determine how its visibility changes, as Spica rises ever earlier as spring progresses.

Sunrise: 6:58 A.M.
Sunset: 7:16 P.M.
Moonrise: 1:31 P.M.
Moonset: 4:08 A.M.
Moon Phase: Waxing gibbous (70%)

Wednesday, March 24
This month marks 240 years since William Herschel’s official discovery of Uranus. Tonight, you can try finding the magnitude 6 ice giant for yourself once full darkness falls. Look west to locate the Pleiades (M45), then drop down about 21.5° to spot the planet. Because it is low on the horizon and a bright, waxing Moon is in the sky, its barely naked-eye brightness might be overwhelmed — instead, use binoculars or a small scope to see it.

Uranus’ disk currently spans 3″ and will appear as a “flat” gray star through your eyepiece. It sets a few hours after sunset, so look earlier rather than later for the best views.

If you miss Uranus, Mars is still nearby, now located 12° east of the Pleiades and 7.3° north-northeast of Aldebaran.

Sunrise: 6:56 A.M.
Sunset: 7:17 P.M.
Moonrise: 2:36 P.M.
Moonset: 4:52 A.M.
Moon Phase: Waxing gibbous (79%)

Thursday, March 25
As soon as Jupiter rises high enough to view from your location this morning, you’ll want to train your telescope on the giant planet, where two of its moons are keeping things exciting. Around 6:25 A.M. EDT, you’ll see Ganymede already in front of the gas giant’s eastern limb. But keep watching — minutes later, Io will pop out from behind the planet, also to its east.

As dawn brightens the sky, Ganymede continues across the disk as Io pulls farther away. Zoom out a bit and you’ll see Europa just over 2′ to Jupiter’s east, while Callisto sits nearly 3′ to the planet’s west. See how long you can follow Ganymede’s journey with the rising Sun quickly approaching.

Sunrise: 6:55 A.M.
Sunset: 7:18 P.M.
Moonrise: 3:46 P.M.
Moonset: 5:32 A.M.
Moon Phase: Waxing gibbous (87%)

Friday, March 26
Venus is in superior conjunction at 3 A.M. EDT. Although it rises with the Sun and isn’t visible, several other planets are lined up for you to enjoy early this morning. An hour before sunrise, Saturn and Jupiter have cleared the horizon amid the stars of Capricornus. Saturn is higher (12°) but fainter (magnitude 0.6) than Jupiter (7°), which is magnitude –2.

Just 30 minutes before sunrise, Mercury — located in Aquarius — has cleared the horizon. It’s bright at magnitude –0.2 but difficult to make out in the growing twilight. The tiny planet sits just over 23° east of Jupiter; if you choose to find it with binoculars or a telescope, make sure to put your optics away several minutes before sunrise to avoid causing unintended damage to your eyes.

Sunrise: 6:53 A.M.
Sunset: 7:19 P.M.
Moonrise: 4:58 P.M.
Moonset: 6:06 A.M.
Moon Phase: Waxing gibbous (94%)

To our early ancestors, Mercury was an oddity. The tiniest planet in the sky, it was also the quickest. And its rapid motion across the heavens earned it a measure of repute as the fleet-footed messenger of the gods — from the Babylonian Nabu to the Greek Hermes to the root of its modern name, the Roman Mercurius.

Mercurius’ divine attributes included trickery, thievery, and good fortune. All three of which fell crisply into alignment ten years ago today, when an interplanetary probe called MESSENGER was snatched from space by Mercury’s weak gravity, forever changing our understanding of this little-known world at the solar system’s ragged inner edge.

Mariner 10 scouts Mercury first

MESSENGER was only the second probe to venture to Mercury, and it came three decades after Mariner 10 completed a whistle-stop tour and three close-range flybys between 1974 and 1975. But Mariner 10’s trajectory meant it could only see the diminutive world’s eastern hemisphere. As such, only 45 percent of Mercury’s surface was visible; the rest lay hidden in darkness.

Still, Mariner 10 revealed clues about the barren, broiling world, which sits three times closer to the Sun than Earth. In the coal-black mercurian sky, the Sun appears 11 times brighter and three times bigger than it does on Earth, and it bakes the planet to many times hotter than humans could ever endure.

Mariner 10 saw rugged highlands and smooth lowlands, not unlike the Moon, although their nature differed on account of Mercury’s stronger gravity. Chains and clusters of craters seemed to flank the highlands, and the immense Caloris Basin — a 3.85-billion-year-old impact feature ringed by forbidding mountainous scarps — came teasingly, but only partially, into Mariner 10’s view.

The probe detected Mercury’s tenuous exosphere of hydrogen and helium atoms seized from the solar wind, as well as a massive planetary core rich in iron and nickel. Surface temperatures were found to swing like a searing pendulum, ranging from 750 degrees Fahrenheit (400 degrees Celsius) during the day to ­­–290 degrees Fahrenheit (–180 degrees Celsius) at night. Surprisingly, Mariner 10 also found Mercury has an intrinsic magnetic field, and though it’s a hundred times feebler than Earth’s, it does weakly shield the planet from the charged particles of the solar wind.

Yet, the most improbable discoveries about Mercury came after Mariner 10 was gone. For instance, radar observations revealed bright spots near the tiny planet’s north and south poles that suggested, even in this hellish place, water-ice deposits could survive on the floors of Mercury’s permanently shadowed craters.

Another mission to Mercury was desirable, but inherently difficult.

Reaching the closest planet to the Sun is far tougher than reaching the farthest. That’s because as a probe falls inward toward the Sun, it picks up speed, which would cause it to sweep past Mercury too fast to be captured by its weak gravity. But by swinging by Earth once, Venus twice, and Mercury three times, such a craft would be able to use these planets’ combined gravities to slow itself down enough to gently drop into mercurian orbit.

And that’s exactly the approach MESSENGER took to become the first spacecraft to enter orbit around Mercury.

MESSENGER goes to Mercury

NASA cleverly tailored this spacecraft’s name using their tried-and-true “backronym” technique, where MESSENGER was made to stand for MErcury Surface, Space, ENvironment, GEochemistry, and Ranging. The probe launched atop a Delta II rocket from Cape Canaveral on August 3, 2004.

Standing six feet (1.8 m) high and boasting a graphite-epoxy frame and protective shield made of ceramic fabric, MESSENGER carried seven instruments to probe Mercury. Its cameras would map the planet at resolutions better than 800 feet (250 meters) per pixel. Gamma-ray, X-ray, and neutron spectrometers would seek out polar ice and examine mineralogical features. And other sensors would scan Mercury’s exosphere, study its magnetic field, measure its landforms, and determine the strength of its gravitational field.

After initially barreling away from Earth at 24,000 miles per hour (38,600 km/h), MESSENGER returned to our planet in August 2005, passing high over central Mongolia while calibrating its scientific toolkit. Two encounters with Venus followed in October 2006 and June 2007. MESSENGER then swept within 125 miles (200 km) of Mercury itself three separate times between January 2008 and September 2009.

During those flybys, MESSENGER imaged almost all of Mercury’s previously unseen western hemisphere, capturing 98 percent of the planet’s surface, with only the polar regions remaining out of sight — at least for the time being. It discovered the 440-mile-wide (715-kilometre) Rembrandt crater (one of Mercury’s youngest craters) and revealed huge chains of cliffs snaking across the surface. The craft also spotted an enigmatic series of narrow, flat-floored troughs — nicknamed “the spider,” but known today as Pantheon Fossae — near the center of Caloris basin. And the size of Caloris itself was refined to 960 miles (1,550 kilometers), making it the largest impact feature on Mercury.

MESSENGER’s flybys of Mercury also revealed that nearly half of the planet’s surface is covered by smooth plains, that the world’s magnetic field is being actively produced deep within its partially molten core, and that volcanism was a key long-term player in mercurian geology.

In other words, even the early parts of MESSENGER’s mission were packed with valuable science.

MESSENGER enters orbit around Mercury

MESSENGER’s early flyby appetizers may have whetted researchers’ scientific appetites. But they paled in comparison to the entrée, which officially began when the probe fired its main engine for 15 critical minutes on March 18, 2011, allowing it to slip into orbit around Mercury.

A new era of exploration was finally underway.

MESSENGER’s elliptical orbit took it within 125 miles (200 km) of Mercury’s surface. But it also ventured as far as 9,300 miles (15,000 km) away to help protect itself from heat radiated by Mercury’s scorching surface. Its year-long primary mission uncovered unexpectedly high concentrations of magnesium and calcium on Mercury’s dark side, found clues pointing to past volcanism, and showed its magnetic field was offset far to the north of the planet’s center.

With its mission extended to March 2013, MESSENGER went on to completely map the tiny planet’s entire surface. It found that Mercury’s core accounts for up to 85 percent of the world’s radius. And it identified over 50 primordial pyroclastic flows from low-profile shield volcanoes, mainly appearing within impact craters.

Despite MESSENGER’s impressive scientific output throughout its mission, what truly captured the public’s imagination was a find announced by NASA in November 2012. MESSERGER had discovered enormous quantities of nearly pure water-ice near Mercury’s poles. And because that water-ice appeared to only be a few tens of millions of years old, it suggested Mercury might have a means to replenish water on its surface.

A second and final mission extension of two years included a hovering campaign, which brought MESSENGER to still lower altitudes. Yet, the end was nigh; the craft’s low orbit gradually degraded, despite two further altitude boosts.

Finally, on April 30, 2015, MESSENGER impacted the surface somewhere near the 29-mile-wide (47 km) crater called Janáček.

Described by Principal Investigator Sean Solomon as “one of the most resilient and accomplished spacecraft to ever explore our neighboring planets,” MESSENGER traveled 8.7 billion miles (14 billion km), circled Mercury 4,100 times, and snapped almost 300,000 photographs — earning itself a well-deserved place in history.

Just before 10 P.M. local time on Feb. 28, a dazzlingly bright meteor traversed the U.K.’s western sky, glowing for about six seconds. It was so bright, in fact, it was termed a fireball. Hundreds of people who happened to glimpse the sight took to social media to report what they saw, wondering if their eyes had been playing tricks on them — or even if they had just seen a visitor from outer space.

But for astronomers, this was a special and rare treat for another reason: It was a chance to search for any pieces left behind.

From meteor to meteorite

We are all familiar with meteors — the flashes of light produced when a piece of rock or dust from space burns up in our atmosphere. Maybe you’ve even enjoyed watching meteor showers throughout the year. But fireballs are rarer. These exceptionally bright meteors streak across the sky with a magnitude greater than –4. That’s about as bright as Venus at its best.

If a meteor doesn’t completely burn up on entry, anything left falls to Earth as a meteorite. Like the larger space rocks that spawn them, meteorites range widely in size. The 1920 meteorite that landed in Hoba, Namibia, for instance, weighs 66 tons (60 metric tons), while the 1949 Beddgelert meteorite that landed in North Wales in the U.K. weighs only 28 ounces (794 grams). But every piece, no matter how small, tells a unique story.

Catching the fall

Of the approximately 65,000 known meteorites, only 1,206 were seen falling to Earth.

To increase this number, the Natural History Museum in London leads and operates the U.K. Fireball Alliance (UKFAll), which employs a huge network of cameras aimed at the skies above the U.K., recording the bright streaks these rocky fragments leave behind. The pictures taken as part of this project provide vital information about the paths these rocks take through our atmosphere. By comparing images taken from different locations, observers can trace the meteors path to help deduce where surviving fragments may have landed. And using this technique, UKFAll aims to recover such meteorites.

Led by volunteers and staff at the Natural History Museum London, UKFAll is a collaboration between six key camera networks: five operate in the U.K. and Europe, while a sixth spans the globe. Thanks to this collaboration, UKFAll was able to calculate where pieces of the most recent U.K. fireball might have landed, as well as determine where in the asteroid belt the original space rock came from, based on its trajectory when entering the atmosphere.

On the night of the fireball, over a thousand reports came filtering into the U.K. Meteor Observing Network (UKMON), part of UKFAll’s network. These were a mixture of eyewitness reports, footage from doorbell cameras, and photographs. Dedicated UKMON cameras captured this unexpected visitor, too.

When footage showed the fireball fragmenting, hopes were high that some material would be found on the ground. Using information from this network of cameras and footage from the public, UKFAll recreated the fireball’s flight path to determine possible landing sites in Gloucestershire. Mary McIntyre, an active UKMON participant, tells Astronomy, “This is a huge win for citizen science in that so many cameras caught the event across so many networks, and everybody worked together quickly to calculate the strewn field [the area where debris might have landed].”

An exciting find

On March 1st, the Natural History Museum confirmed in a press release that pieces of the meteorite were found on a residential driveway in Winchcombe in the Cotswolds. The black, charcoal-like fragments were quickly retrieved by the Wilco*ck family, who owns the property. Several other fragments were discovered scattered around the local area. The museum has obtained nearly 11ounces (300 g) of material from what’s now officially named the Winchcombe meteorite.

Dated at around 4.6 billion years old, this cosmic sample is especially significant because it’s a type of meteorite called a carbonaceous chondrite. These are some of the most pristine, unaltered material in the solar system. Astronomers believe carbonaceous chondrites come from asteroids in the outer regions of the main belt. And their rare composition of minerals and organic compounds — including amino acids — can provide valuable information about the origin of our solar system, the formation of the planets, and the building blocks of life. Of the thousands of meteorite samples found on Earth, only about 50 are carbonaceous chondrites.

According to the Natural History Museum, it’s been 30 years since a meteorite was last recovered in the U.K., and these fragments are the first known carbonaceous chondrite discovered in the country. Plus, the pieces are in such good condition that they are comparable to the samples returned by space missions, both in quality and quantity.

Sara Russell, a Merit Researcher in Cosmic Mineralogy at the Museum, advised on how to care for the meteorite after it was located. For context, the Japanese Hayabusa2 mission recently returned 0.16 ounce (4.5 g) of material from asteroid Ryugu, which the museum is also helping characterize. And Russell says “The Winchcombe meteorite fall is very timely, as the rock is similar to Ryugu in many ways, and we can use the meteorite to rehearse for mission analyses.”

Ashley King of the museum’s Department of Earth Sciences, who was among the first on the scene when the meteorite was discovered, said, “The opportunity to be one of the first people to see and study a meteorite that was recovered almost immediately after falling is a dream come true!”

After their dramatic and unforgettable arrival, the meteorite fragments that rained down onWinchcombe will now undergo testing so researchers can identify their exact chemical makeup. This testing will also allow them to confirm the validity of the samples and better understand their scientific significance.

Although the bright flash that caught the public’s attention is long gone, the story of the Winchcombe meteorite is just beginning. And for the scientists studying these rare space rocks, thrilling times are ahead.

At this time of year, there’s a “false dusk” visible after sunset. From a dark location, you can see the cone-shaped glow reaching upward from the western horizon, rising through the constellations Aries and Taurus. In the fall, that same glow is known as a “false dawn,” giving the eastern horizon a similar shimmer just before sunrise.

This phenomenon is known as zodiacal light, and it’s produced by sunlight reflecting off tiny dust grains in the inner solar system. Astronomers have long thought this interplanetary dust is simply debris shed by asteroids and comets over the eons. But a chance find by the Juno spacecraft during its journey from Earth to Jupiter has revealed a new possible source for the dust that causes zodiacal light: Mars.

The find was published March 9 in JGR Planets.

Juno gets dusty

After launching in 2011, Juno took a somewhat circuitous route to Jupiter. It first ventured to the asteroid belt between Mars and Jupiter, then back toward Earth, ultimately using our planet’s gravity to help slingshot itself to its final destination, where it’s been working since 2016.

Along the way, one of Juno’s four star-tracking cameras — which snap photos four times a second — searched for undiscovered asteroids by sending back images whenever unknown objects appeared in successive shots. Few candidates were expected, but thousands of photos poured in.

“The images looked like someone was shaking a dusty tablecloth out their window,” said John Leif Jørgensen of the Technical University of Denmark, who led the Juno’s star-tracking project, in a press release. The camera was seeing tiny pieces of debris — just 0.04 inch (1 millimeter) across or smaller — from Juno’s expansive solar panels, blasted away by interplanetary dust slamming into the array at some 10,000 mph (16,000 km/h).

The hardy panels were strong enough to withstand the bombardment, but it essentially turned Juno’s solar arrays into giant dust detectors, allowing researchers to map how zodiacal dust is scattered throughout the inner solar system.

Although the distribution of this dust has long been inferred by the sunlight we see reflecting off it, precise measurements remain scarce. And those measurements that do exist come from detectors a thousand times smaller than Juno’s three 30-foot-long (9 m) solar panels, offering limited insight.

Mapping interplanetary dust

Juno showed that the zodiacal dust cloud spans from roughly Earth’s orbit to about twice the Earth-Sun distance, reaching just beyond the orbit of Mars. At the cloud’s inner boundary, Earth’s gravity keeps it at bay, while Jupiter’s gravity keeps the dust in check at the cloud’s outer edge. Within those bounds, the majority of the dust has orbital properties that closely resemble those of Mars. And that’s why researchers think the Red Planet itself is the origin of much of the dust.

To explore this strange idea, the team modeled how dust with Mars’ orbital properties would interact with Jupiter’s gravity over time, as well as what sunlight reflecting off this dust would look like. And sure enough, their results closely match the actual appearance of zodiacal light seen from Earth.

“That is, in my view, a confirmation that we know exactly how these particles are orbiting in our solar system and where they originate,” said Jack Connerney, Juno’s deputy principal investigator and lead investigator on the spacecraft’s magnetometer instrument, which relies on the four star-tracking cameras to function.

Zodiacal origin: unknown

Despite Juno’s new find, there’s one lingering yet vital question that remains: How does dust from Mars escape the Red Planet’s gravity and spread out between the planets?

The team notes that the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft orbiting the Red Planet has seen significant amounts of dust around the world. But they can’t know for sure where it came from. Although Mars is famous for its planetwide dust storms, the team says there’s no known physical mechanism for boosting dust from these storms into space.

Alternatively, they suggest, dust generated by micrometeoroid impacts on Mars’ moons Phobos and Deimos could be the source. However, once again, they aren’t sure how this dust would escape the gravity of the Mars system and become interplanetary dust.

Regardless of the origin of zodiacal dust, this new understanding of the cloud’s distribution will help mission planners better safeguard future spacecraft against interplanetary dust collisions, which could severely damage delicate instruments.

And remember, the next time you’re lucky enough to spot the zodiacal light in the sky, you might just be looking at tiny pieces of Mars glimmering in sunlight between the planets.

We are living in the midst of an exoplanet revolution.

When I was born, there was no evidence for the existence of planets beyond our solar system. And now? Over 4,000 have been discovered. For all of us, this is a groundbreaking moment, both scientifically and, ultimately, spiritually. For the first time in humanity’s history, we know that Earth is not alone, and that there are many Earth-like planets. Surely, some must harbor life?

In fact, in his book “A Universe in Creation,” biophysicist Roy Gould of the Harvard-Smithsonian Center for Astrophysics, argues that we live in a universe finely tuned for life — from the diversity of chemical building blocks in nature, to the abundance of fertile planets where life could take root.

As a composer, I’ve always been fascinated by science. That interest led me to found the Multiverse Concert Series — a nonprofit organization I founded that serves as a space for artists and scientists to come together and collaborate.

I recently completed one such project with Gould. As an artist, spending time with him and sharing his enthusiasm for the nuances of exoplanet science — how every day we are acquiring new knowledge of our planetary neighbors — lit a fire in my mind. The knowledge that we live in a fertile universe of planets is an undeniable source of hope and optimism for humanity, and one that is sorely needed in these times. I became driven to share this vision as powerfully as I can in my own medium of music. I challenge others to do the same in theirs.

The result of our year-long collaboration was “Octave of Light,” a concept album inspired by the search for life on exoplanets and the clues that might reveal life’s presence: chemical signatures from molecules like water vapor, methane, and oxygen.

In this article, I’ll share the journey of this project, and I invite you to listen along in the player below. We’ll explore the groundbreaking science of exoplanets, the joy of connecting astrophysics to art and music, and the narrative arc that connects atmospheric chemistry to the hunt for extraterrestrial life.

The music of exoplanets

How can music communicate exoplanet science? The connection lies in the physics of waves. Most exoplanets are detected via the transit method — as shadows moving across their parent stars. Sensitive telescopes detect minute fluctuations in the light of a distant star as a planet passes across its surface. A telescope equipped with a spectrograph can split these images into their component wavelengths across the electromagnetic spectrum. The spectrograms, courtesy of Roy Gould, come out looking like this:

Analyzing these spectrograms reveals which wavelengths of light have been absorbed by the planet’s atmosphere as it transits, resulting in a unique spectral signature that indicates its chemical makeup. Some molecules absorb light primarily in pronounced dips at just a few wavelengths, while others give rise to an intricate pattern spanning a wide range of wavelengths.

The limits of our eyes

Although these lines correspond to colors, sadly, our eyes can’t see them. First, they are mostly in the infrared and, therefore, outside of our visible range. But even when transposed — or shifted — into visible frequencies, they are spread too widely to fit within the dynamic range of our eyes. As a composer, I began wondering: If we can’t see exoplanets, could we hear them instead? Compared with the feeble one-octave range (one doubling of frequency) of our eyes, our ears can hear a massive eight to 10 octaves, or 20 to 20,000 Hertz! This is certainly an adequate range in which to fit the exoplanet data, and so I got to work.

Light can be translated into sound because, like sound, light travels as a wave. All waves have the property of wavelength, and the proportions of one wavelength to another are preserved when they are multiplied by a common number. This is how a musical piece can be transposed from one key to another without disturbing its harmonies; multiplying all of the frequencies by 2 will transpose the music up one octave.

As light wavelengths are incredibly short, they needed to be multiplied by a big number to fall within the audible range. I chose 237 — that’s 37 octaves lower than the original frequency. However, because it’s a multiple of 2, the pitch classes are preserved (although rounded to the notes of the equal temperament scale). A note with a pitch of G in the sonification is still a G in the data — just an exceedingly high one!

Sonifying molecules

I began by applying this process to the spectra of individual compounds, as measured in the lab.

Here is the first sonification I made of water vapor, a molecule which has been found in many exoplanet atmospheres:

This spectrum became Track 1 on the album, “Water Romanza”: an ode to water as the harbinger of life as we know it. At the beginning, you can hear soprano Beth Sterling singing the dips of the spectrum as the cantus firmus of the piece, joined by violinist Amelia Sie with the lyrical romanza melody.

Another molecule that crucial to exoplanet science is methane. We all know methane as a flammable gas, but its complex molecular form also allows it to be clearly identified in an exoplanet’s spectrogram. We know that methane can arise via inorganic processes on a planet, but finding methane and oxygen together could suggest the presence of life.

This is because oxygen is so reactive that it quickly combines with methane to produce carbon dioxide and water. Finding an unstable mix of both gases together means they are being continuously produced, perhaps by living things! This revelation became track 3: “Methane,” with a wordless melody for soprano tracing the arc of methane’s unique spectrum.

The sound of exoplanets

By comparing an exoplanet’s spectrum to spectra of individual molecules measured in the lab, scientists can break down the planet’s spectrum into component elements and compounds to learn the contents of its atmosphere. The 4th, 5th, and 6th notes (left to right) in the spectrum of planet WASP 17-b (below) match up to the 3rd, 4th, and 5th notes of the water vapor spectrum. Therefore, we can see — and hear harmonically — that the planet’s atmosphere contains water vapor. Not only this, but the individual dips at approximately 0.58 and 0.768 microns reveal the presence of sodium and potassium, audible respectively as B♭ and F.

This breathtaking feat of deduction at a distance of 1,300 light-years gave rise to the song Wanderers, adapted from narration by Carl Sagan in his Cosmos series. We know so much about our exoplanetary neighbors — they seem so close — and yet how frustrating that we remain earthbound!

We began as wanderers,

We are wanderers still.

We have lingered too long on the shores of the cosmic ocean.

Individual chemical clues can tell us much about a planet’s atmosphere, but what would it take to convince us that life was present on another world? Since the album was completed, an astrophysicist friend of mine, Clara Sousa-Silva of MIT, announced a project indicating the presence of phosphine gas in the atmosphere of Venus — a molecule associated with anaerobic bacteria on Earth. Could our scorching hot neighbor harbor microbial life, hidden in its clouds? The scientific debate is still ongoing. But if planned missions to our sister planet come to fruition, we may know soon.

A formula for life?

The climatic track on the album, “Equals Life,” combines these chemical clues — and their musical equivalents — into a potential recipe for life on an exoplanet. In addition, I include the red edge, which is a striking spectral feature that could indicate the presence of chlorophyll, the green pigments in plant life:

Water vapor + red edge + methane + oxygen = life?

We can see all of these clues in earthshine — the light reflected by Earth that is then reflected by the unlit side of the Moon. By analyzing the spectrum of earthshine, we can get a glimpse of how our own planet might appear from another solar system. This begs the question: If aliens knew where to look, would they know we are here? It’s an incredible thought to ponder.

Beyond these four clues, there are thousands more that astrophysicists are now searching for. Without a doubt, the exoplanet revolution will continue to astound us with tales of Earth-like chemistry on distant worlds.

And what message does our spectrum send out to those looking back? It will shine in an octave of light.

All the science that we contend

Discovered in an octave of light

All our efforts to transcend

Will shine out through the daylight

To the spectrum of our skies

The interplay of art and science

Along my artistic journey, I’ve learned that there are countless more spectral clues for life on exoplanets than the handful I’ve explored in Octave of Light. Certainly, the possible presence of phosphine on Venus seems incredibly promising for investigation. I feel that I am going to be very busy…

Together, artists and scientists can discover and celebrate our fortunate place in a fertile universe of planets. We are lucky to be here. This needs to be said — in as many ways as humanity has to offer.

Listen to Octave of Light performed live at Other Skies: An Exoplanetary Festival, streaming on March 20th. The event is free for students at www.otherskies.org.

After three years of development and testing, Unistellar, a company based in Marseilles, France, launched the eVscope’s Kickstarter fundraiser October 25, 2017. In just 30 days, the campaign raised $2.2 million with more than 1,600 people pre-ordering an eVscope for $1,299. The campaign and subsequent videos promised a lot. So, naturally, I couldn’t wait to try it out.

Unistellar shipped me the eVscope and its tripod in one large box. In it were two smaller packages: One held a well-padded backpack that protected the telescope — a 4.4-inch f/4 reflector with a mirror made of borosilicate-crown, a high-grade glass. The other box contained an aluminum tripod.

Setting up

The first step is to charge the battery of the eVscope. Make sure to do this several hours before your observing session, as Unistellar states that it takes seven hours to fully charge the battery. The company provides an adapter that plugs into any outlet within a range of 100 to 240 volts AC. The other end, which outputs 5.0 volts at 2.4 amps, connects to the bottom of the scope. Inside is a 15,000-milliamp-hour battery, which, the company claims, will run the scope for nine hours. If you aren’t sure the battery is full, you can use the scope while it’s charging.

Download Unistellar’s app from the Google Play Store or the Apple Store. On your phone, select “Settings” and then “Wi-Fi” and connect to evScope network. Its name consists of “eVscope” and six random characters. Once connected, you can move to the next steps.

When outdoors, your first task is to find a viewing location and level the tripod. Unistellar makes this easy by incorporating a bubble level at the top of the tripod. This is also the time to set the tripod’s height. Each leg has two locking extenders. I settled on a height where one of the extenders was all the way out. Also at the top of the tripod, you’ll find two knurled knobs. Loosen them so you can insert the scope’s round bottom into the tripod. Then tighten the screws.

Turn on the eVscope by pressing the button on its side for one second. In a few more seconds, the light changes from purple to red, and the scope is ready to go.

Focus and alignment

Launch the Unistellar app. Even with my old phone, it booted up and worked flawlessly.

Select the “eVscope” icon at the bottom (the leftmost of the five icons). From your phone, use the arrow buttons to move the scope to roughly 45°. The purpose here is to find some stars that will enable you to focus the scope. If you don’t see stars, play with the arrow buttons until you do. You’ll also find the large round focus knob at the bottom of the scope. For an initial focus, align the mark on the knob to the top screw. Then, either watching the display on your phone or looking through the eyepiece, adjust the knob to achieve the best focus.

To focus the non-interchangeable eyepiece, turn it clockwise or counterclockwise. Unistellar has built a Bahtinov mask into the main dust cap to help you achieve the best possible focus. First, twist the mask to separate it from the dust cap, and install it the same way you would the cap. Then, touch the “Explore” icon, the one that looks like Saturn with three stars (or moons?) around it. Scroll down to “Stars,” and select any bright star. Then hit the “Go to” button.

With the star centered and the Bahtinov mask on, you’ll see a pattern (called a diffraction pattern) that looks like an X with a central vertical line through it. Your job is to use the bottom knob to focus until the vertical line cuts through the center of the X. When that’s done, remove the mask.

Next, touch the “Automated Alignment” icon to the right of the joystick. It looks like a target. By doing this, you’ll engage one of the coolest features of the eVscope. The built-in computer will compare the star field you found to its database. When finished — it takes about 15 seconds — the scope will be aligned to the sky. At this point, you’ll see “Sky Tracking On” and you’re ready to observe.

Enhanced viewing

Touch the “Explore” icon at the bottom. You’ll find eight rows of objects on the display that the eVscope calculated are visible in your sky: “Recommended,” “Galaxies,” “Nebulae,” “Clusters,” “Stars,” “Planets,” “Transient Events,” and “Advanced.” You can scroll through each row to choose from 10 objects, or, in the case of the bottom three rows, as many as are visible. Each of the top seven rows has a “See all” option, which lists more. “Galaxies,” for example, had 92 entries at one point.

Touching one of the object buttons moves you to another screen. One of its windows shows the object’s altitude (in degrees) and azimuth (as a compass point, such as “NNE”). The window below that provides some additional info on the object. There’s also the “Go to” button.

When you touch “Go to,” the scope moves until your selected object is in the field of view, both through the eyepiece and on your phone. You’re in “Live View” mode. Try not to be disappointed by the view. Remember, it’s a 4.4-inch scope. In this mode, the icon at the upper right will allow you to adjust “Gain” and “Exposure time.” Have some fun playing with these controls. You’ll notice that the two sliders below, “Contrast” and “Brightness,” are locked.

But the coolest thing happens when you touch the icon that looks like an eye with a star and enter “Enhanced Vision Mode.” After a few minutes (it varies depending on your settings), during which the telescope is collecting light from the chosen object, the app will show nebulosity where none was visible before, arms of spiral galaxies where only a hazy core showed, and as many as a dozen times more stars within clusters — all with color.

If you like what you see, touch the “Download” icon at the top to save your image. You can view them later by tapping the “Gallery” icon at the bottom.

When you finish observing, touch “User,” and then hit “Park My eVscope” to send the unit to its home position. Replace the caps, and you’re done.

Evaluation

Even during Tucson’s monsoon season, many nights are clear, so clouds weren’t a problem. But, I was testing the eVscope during the height of the West Coast wildfires. There were days that meteorologically were “sunny,” but I could not see the Sun. The night sky was just as bleak.

I did, however, enjoy extended views of more than a dozen objects. They included the Dumbbell Nebula (M27), which revealed its characteristic shape, the Hercules Cluster (M13), which filled the eyepiece with sharp points of light, and the Wild Duck Cluster (M11), which abounded with colorful stars. And every object looked much better in Enhanced Vision mode than in Live View.

Unistellar has created a nearly foolproof instrument that even novice skywatchers will have a blast with. And by the time you read this, version 1.1 of the software, which incorporated some requests by users, should be installed. Have fun!

How do astronauts go to the bathroom in space? – Henry D., age 7, Cambridge, Massachusetts

Whether you use a hole in the ground or a fancy gold-plated toilet, on Earth, gravity pulls your waste down and away from you. For astronauts, “doing their duty” is a bit more complicated. Without gravity, any loose drops or dribbles could float out of the toilet. That’s not good for astronauts’ health, nor for the sensitive equipment inside the space station.

I study volcanoes on other planets, and I’m interested in how people can work in extreme environments like space.

So how do you go to the bathroom in space or on the International Space Station? Carefully – and with suction.

A bathroom vacuum

In 1961, Alan Shepard became the first American in space. His trip was supposed to be short, so there was no plan for pee. But the launch was delayed for over three hours after Shepard climbed into the rocket. Eventually, he asked if he could exit the rocket to pee. Instead of wasting more time, mission control concluded that Shepard could safely pee inside his spacesuit. The first American in space went up in damp underwear.

Fortunately, there’s a toilet on the space station these days. The original toilet was designed in 2000 for men and was difficult for women to use: You had to pee while standing up. To poop, astronauts used thigh straps to sit on the small toilet and to keep a tight seal between their bottoms and the toilet seat. It didn’t work very well and was hard to keep clean.

So in 2018, NASA spent US$23 million on a new and improved toilet for astronauts on the International Space Station. To get around the problems of zero-gravity bathroom breaks, the new toilet is a specially designed vacuum toilet. There are two parts: a hose with a funnel at the end for peeing and a small raised toilet seat for pooping.

The bathroom is full of handholds and footholds so that astronauts don’t drift off in the middle of their business. To pee, they can sit or stand and then hold the funnel and hose tightly against their skin so that nothing leaks out. To poop, astronauts lift the toilet lid and sit on the seat – just like here on Earth. But this toilet starts suctioning as soon as the lid is lifted to prevent things from drifting away – and to control the stink. To make sure that there is a tight fit between the toilet seat and the astronauts’ behinds, the toilet seat is smaller than the one in your house.

After the deed is done

Pee is more than 90% water. Since water is heavy and takes up a lot of space, it is better to recycle pee rather than bring up clean water from Earth. All astronaut pee is collected and turned back into clean, drinkable water. Astronauts say that “Today’s coffee is tomorrow’s coffee!”

Sometimes, astronaut poop is brought back to Earth for scientists to study, but most of the time, bathroom waste – including poop – is burned. Poop is vacuumed into garbage bags which are put into airtight containers. Astronauts also put toilet paper, wipes and gloves – gloves help keep everything clean – in the containers too. The containers are then loaded into a cargo ship that brought supplies to the space station, and this ship is launched at Earth and burns up in Earth’s upper atmosphere.

If you’ve ever seen a shooting star, it might have been a meteorite burning up in Earth’s atmosphere – or it might have been flaming astronaut poo. And the next time you have to pee or poop, be thankful that you’re doing it with gravity’s help.

This story was originally published on The Conversation. Read the original here.

Friday, March 12
It’s time to get your Messier marathon on! This weekend is the ideal time to run this year’s Messier marathon, during which observers challenge themselves to find every object in the famous comet hunter’s catalog in a single night. All you need is binoculars or a small scope, some dedication, and possibly some caffeine and snacks to keep you going all night long as you tick off each object on the list.

Some of the most popular and easy-to-spot Messier objects are the Orion Nebula (M42), the Pleiades (M45), the Beehive Cluster (M44), the Great Globular Cluster in Hercules (M13), and the Andromeda Galaxy (M31).

But maybe you don’t have time to run a full marathon. In that case, consider challenging yourself to find one of the one of the faintest objects on the list: M97, also known as the Owl Nebula. This magnitude 11 planetary nebula is located in Ursa Major, about 2.3° southeast of magnitude 2 Merak. The nebula requires a 3-inch telescope or larger to spot, and typically appears gray-green to the human eye. In larger scopes, you may notice two dark patches within the spherical remnant that are reminiscent of an owl’s eyes.

For more tips on how to run a Messier marathon, we’ve got you covered over here: It’s time for the 2021 Messier marathon!

Sunrise: 6:16 A.M.
Sunset: 6:04 P.M.
Moonrise: 6:19 A.M.
Moonset: 5:25 P.M.
Moon Phase: Waning crescent (1%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 12 P.M. local time from the same location.

Saturday, March 13
Today’s New Moon makes it perfect for not only observing the full catalog of faint Messier objects, but another faint feature of the night sky as well: the zodiacal light. Visible after sunset at this time of year, this cone-shaped glow is generated by sunlight scattering off dust left by comets and asteroids as they make their way through the inner solar system.

At least, that’s the historically accepted explanation — but new observations with the Juno probe currently circling Jupiter suggest that perhaps martian dust might be responsible for the zodiacal light.

Regardless of its source, for the best chance of spotting the zodiacal light, look west after twilight for a spear of light rising up through the constellations Aries and Taurus. The darker your sky and the higher your elevation, the more likely it is you’ll see it. The zodiacal light is a popular astrophotography target as well; a wide-angle lens on a camera capable of taking 15- to 30-second exposures should be all you need to get an amazing shot.

Sunrise: 6:14 A.M.
Sunset: 6:05 P.M.
Moonrise: 6:45 A.M.
Moonset: 6:26 P.M.
Moon Phase: New

Sunday, March 14
Daylight saving time begins this morning at 2 A.M. local time, meaning that instead of striking 2 A.M., your clock will skip right from 1:59 A.M. standard time to 3 A.M. DST.

Saturn now rises by 5:20 A.M. local time, with Jupiter following half an hour later. Mercury rises around 6:20 A.M. local time, giving you far less time to spot the speedy planet than earlier this month. It’s now a bright magnitude 0, but only 3° high by 6:40 A.M. The tiny world lies in Aquarius, just over the border from Capricornus, where you’ll find the gas giants higher in the sky. By this time, few stars remain visible in the growing twilight. Only the brightest still peek out, including Altair, Deneb, and Vega — the familiar Summer Triangle’s bright points.

Sunrise: 6:12 A.M.
Sunset: 6:06 P.M.
Moonrise: 7:09 A.M.
Moonset: 7:27 P.M.
Moon Phase: Waxing crescent (2%)

Monday, March 15
Asteroid 4 Vesta sits right between a pair of 6th-magnitude stars (HIP 54319 and HIP 54470) in Leo the Lion tonight. The magnitude 6 main-belt asteroid should be easy to find with binoculars, just 3.4° southwest of Zosma. Seeing the asteroid move in a single observing session is challenging, but you can use the two field stars to chart Vesta’s motion over the next few days to really see it slide against the background.

If you’re still in a Messier mood, Leo contains five of Messier’s objects, all galaxies: M65, M66, M95, M96, and M105. M66 is the brightest at magnitude 8.9, located about 2.8° southeast of Chertan and part of the famous Leo Triplet of galaxies, which also contains NGC 3628 and M65. The brightest two of the three, M65 and M66, are visible in nearly any binocular, although you’ll want large binoculars (70mm) or a small scope to bring the edge-on spiral NGC 3628 into view.

Sunrise: 7:11 A.M.
Sunset: 7:08 P.M.
Moonrise: 8:32 A.M.
Moonset: 9:27 P.M.
Moon Phase: Waxing crescent (5%)

Tuesday, March 16
The Moon passes 3° south of Uranus at 10 P.M. EDT. Our satellite, less than four days old and only 12 percent lit an hour after sunset, currently straddles the border between Cetus and Aries. Just visible along the lit lunar edge is Mare Crisium, the Sea of Crises. This dark, round feature is roughly 3.9 billion years old and spans about 460 miles (740 kilometers). On its western side are two small craters: Pierce to the south and Swift to the north. And north of the mare’s rim is the large crater Cleomedes, which stands out in stark relief now but will begin to disappear as the Moon grows closer to Full, losing contrast along the way.

Sunrise: 7:10 A.M.
Sunset: 7:08 P.M.
Moonrise: 8:55 A.M.
Moonset: 10:26 P.M.
Moon Phase: Waxing crescent (10%)

Wednesday, March 17
As Jupiter rises this morning, its innermost moon, Io, is transiting across the disk. By 6 A.M. CDT, Io stands close to the planet’s western limb, ready to slip off less than 10 minutes later. It’s a great view: all four Galilean moons are visible, with Io now sitting between Jupiter and Earth. Europa is to Jupiter’s west, while to the east are Callisto (closer in) and Ganymede. Callisto lies just 9″ from a field star, so don’t confuse the two.

Jupiter itself spans 34″ and shines at magnitude –2. The gas giant’s visibility will only continue to improve over the next several months as it heads for opposition later this year, so don’t worry if its proximity to the horizon makes it challenging to see right now. Better days are coming!

Sunrise: 7:08 A.M.
Sunset: 7:09 P.M.
Moonrise: 9:21 A.M.
Moonset: 11:26 P.M.
Moon Phase: Waxing crescent (17%)

Thursday, March 18
The Moon reaches apogee, the farthest point from Earth in its orbit, at 1:03 A.M. EDT. It will then stand 251,812 miles (405,252 km) from our planet.

Tonight, the Moon stands in Taurus; look west of this constellation to find Aries the Ram, whose brightest star is magnitude 2 Hamal. The star’s name, appropriately, means “the lamb” in Arabic. Nearly 10.5° south of Hamal is Uranus, which, at magnitude 5.9, is near the limit for naked-eye observing. If you’re in a particularly dark, clear location, you may be able to spot it. If not, binoculars will easily show its 3″-wide blue-gray disk.

Continue about 13.5° southeast of Uranus and you’ll find Menkar, the magnitude 2.5 alpha star of Cetus the Whale. Although Cetus’ star Mira (12.8° southwest of Menkar and now very close to the horizon) is a more well-known variable star, Menkar is also variable, changing in brightness by about six percent with no known regular period.

Sunrise: 7:06 A.M.
Sunset: 7:11 P.M.
Moonrise: 9:48 A.M.
Moonset: —
Moon Phase: Waxing crescent (24%)

Friday, March 19
The Moon passes 1.9° south of Mars at 2 P.M. EDT. You can find the pair high in the west at sunset, now just over 3° apart. Mars shines at magnitude 1.1 — a tad fainter than magnitude 0.9 Aldebaran, the nearby red giant eye of Taurus the Bull. The Red Planet is tracking relatively quickly across the sky from night to night; in just a few days, it will stand due north of the star.

Mars spans a mere 6″ on the sky, making it difficult to discern any surface features unless you’re experienced with video capture. But if you’re looking for a breathtaking sight, look no further than the Pleiades (M45), less than 10° to Mars’ west and along a line connecting the Moon and Mars. It’s a great cosmic lineup that you don’t need optical aid to enjoy.

Sunrise: 7:05 A.M.
Sunset: 7:12 P.M.
Moonrise: 10:19 A.M.
Moonset: 12:25 A.M.
Moon Phase: Waxing crescent (33%)