
Sky
Why you can see the moon in the daytime sky
The moon spends almost as much time up in daylight as at night, and on the right days it sits plainly in the blue sky.
Each one says when to look, how to notice it, and where the facts come from.

Sky
The moon spends almost as much time up in daylight as at night, and on the right days it sits plainly in the blue sky.

Sky
Ice crystals high in the atmosphere can bend sunlight into a pale ring around the sun or bright patches on either side of it.

Sky
When broken clouds and haze meet a low sun, bright and dark bands can fan across the sky near sunrise or sunset.

Sky
Where the sun sets on your skyline slides north through spring and south through autumn, fastest near the equinoxes and nearly still at each solstice.

Sky
From the September equinox to the December solstice the midday sun drops from about 47 to about 24 degrees here, and your noon shadow more than doubles.

Sky
From eastern Massachusetts the Big Dipper is circumpolar, circling Polaris once a day, though the tip of its handle skims the horizon at its lowest.

Sky
The Andromeda Galaxy, a spiral galaxy 2.5 million light-years away, is well placed in the evening sky from autumn into winter. Binoculars help.

Sky
Vega, Deneb and Altair, the Summer Triangle, stay up after dark in autumn: high in the south in September and October, west by November.

Sky
A clear full moon casts a sharp shadow. Moonlight is reflected sunlight, hundreds of thousands of times fainter than direct sun.

Sky
Between the fall equinox and the winter solstice each day is a little shorter, up to about 20 minutes a week, fading near the solstice.

Sky
On rare strong geomagnetic storm nights the northern lights may glow low in the north, and a phone camera can show color the eye misses.

Sky
Stars twinkle because they are single points of light; a bright point that shines steady is often a planet, a tiny disk instead.

Sky
A rising full moon looks huge but measures the same width as it does higher in the sky. Test it with your fingernail.

Sky
On a thin crescent Moon the dark part of the disk can glow faintly, lit by sunlight that bounced off Earth first.

Sky
Satellites, including the International Space Station, glide across the sky as steady points of light after sunset and before sunrise, lit by sunlight.

Sky
A narrow shaft of light standing up from the sun at sunrise or sunset, made by glints from millions of nearly flat ice crystals drifting level.

Sky
On a clear evening a dark blue-gray band rises low in the east after sunset. It is the shadow of the Earth, with the pink Belt of Venus above it.

Weather
A cold, calm morning can outline leaves, seed heads, webs and tracks in frost crystals that vanish soon after sunrise.

Weather
When surfaces cool below the dew point, water vapor condenses into droplets on grass, cars and webs by morning.

Weather
Fine dew droplets outline webs that are almost impossible to see in dry air, so one still, humid night can reveal every strand around the yard.

Weather
On clear, calm fall nights the ground loses heat, cool air slides downhill, and by dawn low fields and river meadows hold pools of fog that clear in hours.

Weather
On a clear calm night the air at your feet ends up colder than the air above, and that flipped layer bends sound back down so it carries much further.

Weather
A nor'easter is a coastal storm named for the northeast wind over the coast, though the storm itself usually moves up the coast toward the northeast.

Weather
Stand with your back to a steady wind and the center of low pressure lies off to your left, a little ahead.

Weather
A short-lived contrail means relatively dry air high up; one that lingers and spreads means the air up there holds a lot of moisture.

Birds
Before migrating, chimney swifts in eastern Massachusetts gather at dusk and pour into big old chimneys to roost, hundreds swirling in like water.

Birds
From mid-August into early September, common nighthawks drift south over eastern Massachusetts in loose evening flocks, catching insects as they go.

Birds
Ruby-throated hummingbirds leave Massachusetts between late August and late September, feeding hard at late-summer flowers and feeders until they go.

Birds
After their late nesting season, American goldfinches molt in late August and September, trading lemon yellow for gray-brown and looking patchy between.

Birds
Once the flightless summer molt ends in late July, Canada goose families in eastern Massachusetts pool into growing flocks that graze fields and use ponds.

Birds
In late summer the year's young eastern screech-owls leave their nests and call in the dark, a shivery whinny or a soft trill, while seeking territories.

Birds
For a brief window centered on mid-September, broad-winged hawks pour out of New England in soaring flocks called kettles, bound for South America.

Birds
Warblers move south through Massachusetts from late August to late October, drab and silent in fall, and the way to find them is to follow the chickadees.

Birds
From mid-September, white-throated sparrows that summered in the north woods return to Massachusetts yards, scratching in the leaf litter and whistling.

Birds
A blue jay can carry up to five small acorns at once and may hide 3,000 to 5,000 nuts in a season, so the loud jay parties in the oaks are a harvest crew.

Birds
In fall, hens and their grown broods join forces, and New England turkey flocks commonly hold several families, 40 or more birds, sweeping across fields.

Birds
Autumn starling flocks in Massachusetts fly as one shape-shifting cloud, turning in unison because no falcon can pick one bird out of a swirl of thousands.

Birds
In late August, barn swallow families line up on roadside wires as the last chicks fledge; most leave for Central and South America by mid-September.

Birds
Goldfinches raise chicks after other songbirds are done, waiting for late summer, when seed fluff for nest lining and ripe seeds for chicks arrive at once.

Birds
Late-summer feeders turn up cardinals and blue jays with bare black heads. Most are this year's young losing every head feather at once in a first molt.

Birds
Most songbirds migrate after dark and call as they fly, and from an ordinary yard the thrushes are within earshot: a soft short peep from the black sky.

Birds
Crows and common ravens are both big black birds, and the tail settles it at a glance: a crow's opens like a fan, a raven's like a wedge.

Birds
Pileated woodpeckers chisel large rectangular holes into dead trees, stumps and logs to reach carpenter ants, leaving big wood chips below.

Birds
Owls cough up the fur and bones of prey as pellets, and under a roost tree they reuse, pellets and white droppings can pile up.

Birds
A small rusty-brown wren with a white eyebrow that lives in Massachusetts all year and is one of the few birds that sings in every month.

Birds
The brown creeper is a small streaky-brown bird that looks like bark and climbs trunks from the bottom up, then flutters to the next tree.

Birds
The white-breasted nuthatch climbs down tree trunks headfirst and hangs under branches, which woodpeckers and brown creepers cannot do.

Birds
The two look nearly identical. Compare the bill to the head: short and stubby on the downy, nearly as long as the head on the hairy.

Birds
A belted kingfisher announces itself with a dry rattle, hovers over water, and plunges headfirst for a fish. The female is the more colorful one.

Birds
The spotted sandpiper bobs the back half of its body as it walks the water's edge. In this species the female courts the males.

Birds
The green heron is a small heron so good at hiding in cover that it often goes unseen until it flushes with a loud skeow.

Birds
Piping plovers nest on open sand and treat dogs as predators, so many Massachusetts beaches ban dogs or require leashes through summer.

Birds
Mount Tom State Reservation allows dogs on its trails, and Mass Audubon names it one of the state's best fall hawk-watching places.

Birds
Blue Jays often copy the screams of Red-shouldered and Red-tailed Hawks, so a hawk call from a yard tree is worth a look before you name it.

Birds
The Barred Owl's hoot is a run of 8 to 9 notes that people hear as 'Who cooks for you?' Barred Owls live in Massachusetts year-round.

Insects
Monarchs emerging in eastern Massachusetts from about mid-August put breeding on hold, live for months, and fly all the way to mountain forests in Mexico.

Insects
From late August into fall, common green darners stream south through the Northeast, a dragonfly migration flown by the offspring of the spring arrivals.

Insects
As August settles in, eastern Massachusetts nights fill with fall field crickets, shimmering ground crickets, and true katydids up in the treetops.

Insects
A brown husk on a tree trunk is the outgrown skin of a dog-day cicada nymph that climbed up after years underground and split open as a winged adult.

Insects
Many orb weavers eat their worn web and spin a whole new wheel in about an hour after dark, so the crisp web you find at breakfast is often brand new.

Insects
Water striders stand on the surface film of eastern Massachusetts ponds on water-repellent, hairy legs, denting it into dimples without breaking through.

Insects
Crickets are cold-blooded, so the tempo of their chirping tracks the evening air: brisk at dusk and slower as a late-summer night cools off.

Insects
A light that is already burning on a warm, still night, a street lamp or a lit shop front, draws a small sample of the many moths out in the dark.

Insects
Goldenrods and asters bloom into fall in New England, and their pollen and nectar carry bumble bees and migrating monarchs when little else is flowering.

Insects
The black-and-rust fuzzy caterpillars crossing pavement in fall are woolly bears seeking winter shelter, where they freeze nearly solid and thaw in spring.

Insects
Late-summer milkweed pods draw crowds of large milkweed bugs, adults and nymphs together, in orange warning colors borrowed from the plant's toxins.

Insects
The gauzy silk bags wrapping whole branch ends on cherries and other hardwoods are fall webworm nests, with the caterpillars feeding safely inside.

Insects
September is peak mantis season, when the year's mantises are full size in gardens and meadows and females leave foam egg cases on stems for winter.

Insects
When nights turn cool in September, field crickets slip indoors for warmth, so a chirp starts up behind the bookcase or under the basement stairs.

Insects
On warm fall days young spiders climb to a high point, let out silk and ride the wind, a trip that can cover inches or hundreds of miles.

Insects
A green tomato hornworm studded with white capsules has been farmed from the inside by a tiny braconid wasp, and the capsules are its next generation.

Insects
The white caterpillar with black tufts crossing the trail is a hickory tussock seeking a spot for its cocoon, and its barbed hairs give many people a rash.

Insects
On a warm late-August day after rain, ant colonies send out winged queens and males for one mating flight; around Boston it is called the Labor Day ant.

Insects
Flip a ragged milkweed leaf and you may find a gang of fuzzy black, orange and white milkweed tussock caterpillars eating it down to lace.

Insects
The daddy longlegs on the shed wall is a harvestman, not a spider: one body piece, no silk, no fangs, no venom. The most venomous spider story is a myth.

Insects
The gray, teardrop-shaped paper globe in a tree has grown all summer and can hold 100 to 400 hornets; admire the chewed-wood architecture from a distance.

Insects
Multicolored Asian lady beetles swarm onto sun-warmed outside walls each fall, favoring south- and west-facing sides of light-colored houses.

Insects
Some small white tufts drifting through the air in fall are woolly alder aphids, wrapped in waxy threads and flying from alder to silver maple for winter.

Insects
Late in the season yellowjacket workers forage mostly for sugar, crowding picnics, fallen fruit and trash cans until the first hard frost.

Insects
Cluster flies, slightly larger and slower than house flies, gather on sunny walls in autumn looking for a place to spend the winter.

Insects
Held tip up with the opening facing you, a northeastern land-snail shell almost always opens on the right. Physa pond snails coil left.

Insects
A large, harmless brown bug that seeks shelter on sunny walls and indoors in fall. Look for a flat, leaf-shaped flare on each hind leg.

Plants
Along wet, shady edges in eastern Massachusetts, ripe jewelweed pods are coiled springs that burst at the slightest touch and fling their seeds away.

Plants
Oak acorn crops swing widely from year to year and tree to tree, and a heavy year concentrates squirrels, deer, turkeys and more wherever acorns fall.

Plants
The bumps and balls on eastern Massachusetts oak leaves are galls, tissue the tree grew around a tiny wasp or other insect, and most do the tree no harm.

Plants
Late-summer goldenrod patches in Massachusetts gather bees, butterflies and dozens of other insects onto a few bright yellow plumes as other flowers fade.

Plants
Ghost pipe rises in shaded Massachusetts woods from June through September, a waxy white plant with no chlorophyll that feeds through fungi on tree roots.

Plants
Trees in eastern Massachusetts build next spring's buds near the end of the growing season, so by fall every twig tip already carries next year.

Plants
Common milkweed pods on Massachusetts roadsides and meadow edges split in late summer and early fall, each sending off a hundred or more seeds on silk.

Plants
The yellows and oranges of a Massachusetts fall sit hidden in leaves all summer, revealed when shortening days shut down the green chlorophyll over them.

Plants
Goldenrod gets blamed for fall allergies, but its pollen is too heavy and sticky to fly. The real culprit is drab green ragweed, blooming at the same time.

Plants
Weeks before the trees change, Virginia creeper goes deep crimson and poison ivy turns orange and red while everything behind them is still green.

Plants
New England fall color starts in wet spots: red maples, the swamp maples, turn in low ground weeks before the hillsides, sometimes before Labor Day.

Plants
The fox grape, wild parent of the Concord, ripens on New England wood edges in September, and a ripe tangle can smell of grape jelly before you see fruit.

Plants
As its seeds ripen, each flat white Queen Anne's lace flower curls into a brown cup like a little bird's nest, and fields hold both stages side by side.

Plants
Along wood edges and fences, pokeweed grows reddish-purple stems taller than a person, with drooping grape-like clusters ripening green to purple-black.

Plants
Roadside and stone-wall poison ivy goes brilliant red before any maple starts while its berries turn white. The color signals birds that the fruit is ripe.

Plants
Staghorn sumac colonies along roadsides and field edges turn scarlet, orange and gold in early fall, and female plants keep upright red fruit into winter.

Plants
Staghorn and smooth sumac hold upright cones of fuzzy red fruit through winter, which birds pass over until other food runs out.

Plants
White oak group acorns start growing a root soon after they fall, while red oak group acorns wait for spring.

Plants
A young white pine grows one ring of branches, a whorl, for each year of upward growth, so counting the rings estimates its age.

Plants
A light spring band and a dark late band make one ring. Wide rings often mean good years; narrow ones can mean drought or crowding.

Plants
Burs and barbed seeds that hook onto socks and fur on fall walks along field edges, and how to sort and remove them.

Plants
Beechdrops are leafless brownish plants that live only under American beech, feeding on its roots, with small tube flowers in early fall.

Plants
Tar spot is a fungus that leaves raised black blotches, like drips of tar, on maple leaves, largest on Norway maples, and it winters on the fallen leaves.

Plants
Eastern white pine has 5 needles to a bundle, pitch pine 3, and red pine 2 that snap when bent, though some planted pines have 2 as well.

Plants
Some blue-green algae blooms make toxins that can sicken dogs. The state says blooms are most common in summer and early fall.

Mammals
The most common bat in Massachusetts suburbs, the big brown bat, leaves its roost in the evening to hunt insects over yards, ponds and field edges.

Mammals
Each fall gray squirrels bury nuts one at a time across yards and woods, and the caches they never dig up can sprout into oaks, hickories and walnuts.

Mammals
Beavers work mostly at night, so pointed stumps, pale wood chips and paired tooth grooves along a pond edge are often easier to find than the animal.

Mammals
In September and October each chipmunk dash across a yard is a delivery run, cheek pouches holding about 72 sunflower seeds, bound for tunnels underground.

Mammals
A woodchuck grazing a field edge is building the fat it lives on all winter: it is one of Massachusetts' few true hibernators and eats nothing till spring.

Mammals
In early September bucks strip the velvet from their antlers, and through the November rut they leave rubs a foot to three feet up young trunks.

Mammals
The bats over the lawn in August thin out through September and October. Some fly south, and the ones that stay sleep through winter until spring.

Mammals
Red squirrels strip pine, spruce and hemlock cones at a favorite stump or log, and the scales pile up there over years, up to two feet high.

Mammals
Red fox pups born in spring leave their family groups in autumn to find ranges of their own, and some travel a long way.

Mammals
Mass Audubon says porcupines raise their quills rather than shoot them. If a dog is quilled, Cornell says see a veterinarian; do not pull them yourself.

Mammals
The fisher is a large member of the weasel family, not a cat. It lives throughout Massachusetts except on Nantucket and Martha's Vineyard.

Fungi
Each mushroom that appears after a Massachusetts rain is the short-lived fruiting body of a fungus whose threadlike main body stays hidden in soil or wood.

Fungi
Rain turns a lichen's gray outer layer see-through so the green algal partner shows, while lichens with cyanobacteria go dark green, brown or black.

Fungi
Under damp leaf piles in eastern Massachusetts yards and woodlots, microbes, millipedes and earthworms turn dead leaves back into soil nutrients.

Fungi
A white ball the size of a soccer ball in the grass is a giant puffball, one of the largest fungi, and a ripe one holds an estimated seven trillion spores.

Fungi
A yellow blob that appears on mulch overnight is a slime mold: not a fungus but a giant single cell that creeps, eats, then dries into a brown spore mass.

Fungi
Hen of the woods is a big gray-brown mushroom in overlapping rosettes at the foot of living oaks, and the same oak often produces one year after year.

Fungi
Hard black swellings on a roadside cherry's twigs are black knot, a native fungus, not fire damage or an insect gall, and it can keep growing for decades.

Fungi
Honey mushrooms are golden-tan to brown clusters at the base of trunks and stumps from late summer into fall, the fruiting stage of Armillaria.

Fungi
Shaggy manes come up on lawns and roadsides as tall white shaggy caps, then dissolve from the bottom edge into black ink within about a day.

Fungi
A pale green lichen with tiny stalks tipped in bright red, found on old stumps, rotting logs, mossy ground and weathered fence posts.

Fungi
A pale gray-green, hair-like lichen on twigs and branches; it is sensitive to air pollution, and a stretched strand has an elastic cord inside.

Fungi
A hard, gray, hoof-shaped fungus on birch and beech trunks that lives for years and can be seen in every season.

Fungi
The gray, yellow-green and orange crusts on old stone are lichens, a fungus living with an alga, slow growing and differing from one stone type to another.

Fungi
A small fuzzy gray-white fan on dead hardwood whose gills are split down the middle. It shrivels in dry spells and starts working again after rain.

Fungi
The black, deeply cracked lump on a living birch trunk is chaga, a fungus, not a burn scar or a woody burl. It can sit on the tree for many years.

Fungi
Fallen sticks and logs stained bright blue-green are colored by a cup fungus called Chlorociboria. Its tiny turquoise cups appear far less often.

Amphibians
After a soaking summer rain in eastern Massachusetts woods, red efts, the young land stage of the eastern newt, walk the wet leaf litter in daylight.

Amphibians
Snapping turtle eggs laid in early summer hatch from late August through October, and quarter-sized hatchlings walk overland toward ponds and rivers.

Amphibians
Spring peepers call again in autumn from dry upland woods rather than ponds: a single small peep with long silences, often mistaken for a bird.

Landscape
By midsummer most Massachusetts vernal pools are shrinking toward a dry bed of dark leaves, and that regular drying is what keeps fish from settling in.

Landscape
Almost every stone wall in New England woods was a field or pasture edge, built of glacial stones farmers cleared between the Revolution and the Civil War.

Landscape
Some round ponds and deep hollows in eastern Massachusetts mark where a block of ice, stranded and buried as the last glacier retreated, slowly melted.

Landscape
A huge lone boulder in the woods or a field is often not local rock: the last ice sheet carried it from elsewhere and dropped it as it melted.

Landscape
A mound beside a hollow marks a tree blown over long ago, its roots lifting soil and stone that stayed behind after they rotted.

Landscape
An esker is a long, winding ridge of sand and gravel laid down by a meltwater river in a channel within or beneath the last ice sheet.

Landscape
Drumlins are smooth, oval hills of glacial till streamlined by moving ice, and eastern Massachusetts has many of them.

Landscape
A wolf tree is a huge, wide-crowned tree with low thick limbs among straighter younger trees, a likely sign the spot was once a pasture or field edge.

Landscape
MassWildlife raises trout in its hatcheries and stocks them in spring and fall, and posts a stocking report you can search by town or waterbody.

Landscape
Dog rules on Massachusetts trails come from the landowner: DCR, state wildlife lands, Mass Audubon and The Trustees each have their own.

Landscape
Fine parallel scratches and grooves on bare ledges were cut by stones in the base of an ice sheet, and they record which way the ice moved.

Landscape
Roxbury Puddingstone is old gravel of rounded pebbles and cobbles cemented into hard rock. It crops out in ledges and cliffs in and around Boston.