Sky calendar

The next 18 months of things that happen on a date, solved from the ephemeris rather than kept in a list. Almost every one is the same instant for everybody on Earth, so a date here needs no location to be true — what is visible tonight is the list that does depend on where you are standing.

[

Coming up

] SOONEST FIRST
SHOW
+WHAT THE EIGHT KINDS ARE
  • Eclipses solar and lunar, with where on Earth each is greatest.
  • Meteor showers dated by where the Earth is in its orbit, not by a fixed calendar day.
  • Moon phases the four quarters, which set what else is worth chasing that fortnight.
  • Close pairings two bright things within a few degrees of each other.
  • Oppositions the night each outer planet is closest, biggest and up all night.
  • Elongations the mornings and evenings Mercury and Venus stand furthest from the Sun.
  • Equinoxes and solstices the four turning points of the year.
  • Flybys near-Earth asteroids passing inside twenty lunar distances.
FROM WHERE

Pick a place and every event will say which hours are worth being outside for it. Until you do, nothing here is answered for anywhere in particular.

ADD TO YOUR CALENDAR ↓The next twelve months as an .ics file, filtered exactly as you have it here — import it, or subscribe and it stays current.
[

September 2026

] 3 EVENTS
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  • 11
    FRI
    FLYBY--:--

    (2026 OH3) passes at 12.3 lunar distances

    (2026 OH3), somewhere between 146 m and 326 m across depending on how dark its surface is, makes its closest approach to Earth at 12.3 lunar distances (4.7 million km), moving past at 20.17 km/s. At magnitude 21.0 it is far below anything an amateur telescope reaches — this one is a fact rather than a sight. A pass at this range is ordinary rather than alarming — it is the reason the object is tracked, not a reason to worry about it.

    +WHAT TO EXPECT
    SPEED
    20.17 km/srelative to Earth at closest approach
    MISS DISTANCE
    12.3 lunar distances4 731 952 km
    BRIGHTNESS
    magnitude 21.0far below anything an amateur telescope reaches
    SIZE
    146 m – 326 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 17
    THU
    FLYBY--:--

    (2026 NT2) passes at 16.1 lunar distances

    A body somewhere between 240 m and 536 m across depending on how dark its surface is, passing 16.1 lunar distances out at 12.54 km/s.

    +WHAT TO EXPECT
    SPEED
    12.54 km/srelative to Earth at closest approach
    MISS DISTANCE
    16.1 lunar distances6 183 442 km
    BRIGHTNESS
    magnitude 18.0far below anything an amateur telescope reaches
    SIZE
    240 m – 536 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 23
    WED
    SUN--:--

    September equinox

    The Sun crosses back south over the celestial equator, day and night level up again, and the nights start getting longer in the north and shorter in the south.

    +WHAT TO EXPECT

    Nothing to see on the night. What it marks is the shape of the months either side: which way the nights are going, and how much dark you will have to work with.

[

October 2026

] 1 EVENT
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  • 31
    SAT
    FLYBY--:--

    (2025 UK9) passes at 0.8 lunar distances

    A body somewhere between 3 m and 6 m across depending on how dark its surface is, passing 0.8 lunar distances out at 7.83 km/s.

    +WHAT TO EXPECT
    SPEED
    7.83 km/srelative to Earth at closest approach
    MISS DISTANCE
    0.8 lunar distances314 823 km
    BRIGHTNESS
    magnitude 20.1far below anything an amateur telescope reaches
    SIZE
    3 m – 6 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

[

November 2026

] 2 EVENTS
MO
TU
WE
TH
FR
SA
SU
1
2
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  • 2
    MON
    FLYBY--:--

    524522 Zoozve (2002 VE68) passes at 15.7 lunar distances

    A body somewhere between 207 m and 464 m across depending on how dark its surface is, passing 15.7 lunar distances out at 8.72 km/s.

    +WHAT TO EXPECT
    SPEED
    8.72 km/srelative to Earth at closest approach
    MISS DISTANCE
    15.7 lunar distances6 018 535 km
    BRIGHTNESS
    magnitude 15.6far below anything an amateur telescope reaches
    SIZE
    207 m – 464 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 6
    FRI
    FLYBY--:--

    (2001 KF54) passes at 18.8 lunar distances

    A body somewhere between 293 m and 655 m across depending on how dark its surface is, passing 18.8 lunar distances out at 16.42 km/s.

    +WHAT TO EXPECT
    SPEED
    16.42 km/srelative to Earth at closest approach
    MISS DISTANCE
    18.8 lunar distances7 243 615 km
    BRIGHTNESS
    magnitude 15.9far below anything an amateur telescope reaches
    SIZE
    293 m – 655 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

[

December 2026

] 2 EVENTS
MO
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  • 8
    TUE
    FLYBY--:--

    (2016 NV) passes at 14.3 lunar distances

    A body somewhere between 284 m and 634 m across depending on how dark its surface is, passing 14.3 lunar distances out at 10.42 km/s.

    +WHAT TO EXPECT
    SPEED
    10.42 km/srelative to Earth at closest approach
    MISS DISTANCE
    14.3 lunar distances5 478 070 km
    BRIGHTNESS
    magnitude 15.0needs a telescope
    SIZE
    284 m – 634 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 21
    MON
    SUN--:--

    December solstice

    The Sun reaches its furthest south: the longest night of the year in the northern hemisphere, and the shortest in the southern.

    +WHAT TO EXPECT

    Nothing to see on the night. What it marks is the shape of the months either side: which way the nights are going, and how much dark you will have to work with.

[

January 2027

] 1 EVENT
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  • 28
    THU
    FLYBY--:--

    (2020 OP3) passes at 7.6 lunar distances

    A body somewhere between 172 m and 384 m across depending on how dark its surface is, passing 7.6 lunar distances out at 16.86 km/s.

    +WHAT TO EXPECT
    SPEED
    16.86 km/srelative to Earth at closest approach
    MISS DISTANCE
    7.6 lunar distances2 918 357 km
    BRIGHTNESS
    magnitude 18.0far below anything an amateur telescope reaches
    SIZE
    172 m – 384 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

[

March 2027

] 4 EVENTS
MO
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  • 4
    THU
    FLYBY--:--

    474158 (1999 FA) passes at 16.5 lunar distances

    A body somewhere between 192 m and 429 m across depending on how dark its surface is, passing 16.5 lunar distances out at 6.63 km/s.

    +WHAT TO EXPECT
    SPEED
    6.63 km/srelative to Earth at closest approach
    MISS DISTANCE
    16.5 lunar distances6 350 271 km
    BRIGHTNESS
    magnitude 16.6far below anything an amateur telescope reaches
    SIZE
    192 m – 429 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 4
    THU
    FLYBY--:--

    535844 (2015 BY310) passes at 9.2 lunar distances

    A body somewhere between 111 m and 249 m across depending on how dark its surface is, passing 9.2 lunar distances out at 8.02 km/s.

    +WHAT TO EXPECT
    SPEED
    8.02 km/srelative to Earth at closest approach
    MISS DISTANCE
    9.2 lunar distances3 527 630 km
    BRIGHTNESS
    magnitude 16.2far below anything an amateur telescope reaches
    SIZE
    111 m – 249 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 18
    THU
    FLYBY--:--

    506074 Svarog (2015 UM67) passes at 19.0 lunar distances

    A body 665 m across, passing 19.0 lunar distances out at 22.41 km/s.

    +WHAT TO EXPECT
    SPEED
    22.41 km/srelative to Earth at closest approach
    MISS DISTANCE
    19.0 lunar distances7 308 194 km
    BRIGHTNESS
    magnitude 15.2far below anything an amateur telescope reaches
    SIZE
    665 mmeasured

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 20
    SAT
    SUN--:--

    March equinox

    The Sun crosses the celestial equator heading north, and day and night are very nearly equal length everywhere on Earth. Spring begins in the northern hemisphere and autumn in the southern.

    +WHAT TO EXPECT

    Nothing to see on the night. What it marks is the shape of the months either side: which way the nights are going, and how much dark you will have to work with.

[

June 2027

] 3 EVENTS
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TU
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  • 6
    SUN
    FLYBY--:--

    4953 (1990 MU) passes at 12.0 lunar distances

    4953 (1990 MU), somewhere between 2.8 km and 6.3 km across depending on how dark its surface is, makes its closest approach to Earth at 12.0 lunar distances (4.6 million km), moving past at 23.82 km/s. At magnitude 9.9 it is a binocular object, moving fast enough across the stars to watch it move. A pass at this range is ordinary rather than alarming — it is the reason the object is tracked, not a reason to worry about it.

    +WHAT TO EXPECT
    SPEED
    23.82 km/srelative to Earth at closest approach
    MISS DISTANCE
    12.0 lunar distances4 612 019 km
    BRIGHTNESS
    magnitude 9.9a binocular object
    SIZE
    2.8 km – 6.3 kmfrom its brightness, the range covering a reflective surface and a sooty one

    Bright enough to find, and fast enough that the finding is the sport: it moves against the stars while you watch, so what you are looking for is the one point that will not stay put. Have a chart of the field ready before it arrives.

  • 21
    MON
    SUN--:--

    June solstice

    The Sun reaches its furthest north, giving the northern hemisphere its longest day and its shortest, palest nights — and the southern hemisphere the long dark evenings that go with midwinter.

    +WHAT TO EXPECT

    Nothing to see on the night. What it marks is the shape of the months either side: which way the nights are going, and how much dark you will have to work with.

  • 28
    MON
    FLYBY--:--

    456938 (2007 YV56) passes at 19.6 lunar distances

    A body somewhere between 169 m and 379 m across depending on how dark its surface is, passing 19.6 lunar distances out at 17.79 km/s.

    +WHAT TO EXPECT
    SPEED
    17.79 km/srelative to Earth at closest approach
    MISS DISTANCE
    19.6 lunar distances7 530 376 km
    BRIGHTNESS
    magnitude 17.8far below anything an amateur telescope reaches
    SIZE
    169 m – 379 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

[

August 2027

] 3 EVENTS
MO
TU
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FR
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  • 7
    SAT
    FLYBY--:--

    137108 (1999 AN10) passes at 1.0 lunar distances

    A body somewhere between 653 m and 1.5 km across depending on how dark its surface is, passing 1.0 lunar distances out at 26.28 km/s.

    +WHAT TO EXPECT
    SPEED
    26.28 km/srelative to Earth at closest approach
    MISS DISTANCE
    1.0 lunar distances389 781 km
    BRIGHTNESS
    magnitude 7.8a binocular object
    SIZE
    653 m – 1.5 kmfrom its brightness, the range covering a reflective surface and a sooty one

    Bright enough to find, and fast enough that the finding is the sport: it moves against the stars while you watch, so what you are looking for is the one point that will not stay put. Have a chart of the field ready before it arrives.

  • 19
    THU
    FLYBY--:--

    (2017 QW17) passes at 17.8 lunar distances

    A body somewhere between 126 m and 281 m across depending on how dark its surface is, passing 17.8 lunar distances out at 19.86 km/s.

    +WHAT TO EXPECT
    SPEED
    19.86 km/srelative to Earth at closest approach
    MISS DISTANCE
    17.8 lunar distances6 833 077 km
    BRIGHTNESS
    magnitude 17.4far below anything an amateur telescope reaches
    SIZE
    126 m – 281 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 29
    SUN
    FLYBY--:--

    826799 (2023 OE6) passes at 16.7 lunar distances

    A body somewhere between 285 m and 637 m across depending on how dark its surface is, passing 16.7 lunar distances out at 25.21 km/s.

    +WHAT TO EXPECT
    SPEED
    25.21 km/srelative to Earth at closest approach
    MISS DISTANCE
    16.7 lunar distances6 419 848 km
    BRIGHTNESS
    magnitude 16.5far below anything an amateur telescope reaches
    SIZE
    285 m – 637 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

[

September 2027

] 1 EVENT
MO
TU
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  • 23
    THU
    SUN--:--

    September equinox

    September equinox: the Sun crosses the celestial equator and day and night level up.

    +WHAT TO EXPECT

    Nothing to see on the night. What it marks is the shape of the months either side: which way the nights are going, and how much dark you will have to work with.

[

October 2027

] 3 EVENTS
MO
TU
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FR
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  • 16
    SAT
    FLYBY--:--

    (2026 AT6) passes at 19.9 lunar distances

    A body somewhere between 267 m and 597 m across depending on how dark its surface is, passing 19.9 lunar distances out at 10.56 km/s.

    +WHAT TO EXPECT
    SPEED
    10.56 km/srelative to Earth at closest approach
    MISS DISTANCE
    19.9 lunar distances7 650 309 km
    BRIGHTNESS
    magnitude 14.7needs a telescope
    SIZE
    267 m – 597 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 27
    WED
    FLYBY--:--

    250680 (2005 QC5) passes at 18.9 lunar distances

    A body 398 m across, passing 18.9 lunar distances out at 10.88 km/s.

    +WHAT TO EXPECT
    SPEED
    10.88 km/srelative to Earth at closest approach
    MISS DISTANCE
    18.9 lunar distances7 272 829 km
    BRIGHTNESS
    magnitude 17.2far below anything an amateur telescope reaches
    SIZE
    398 mmeasured

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 29
    FRI
    FLYBY--:--

    453707 (2010 XY72) passes at 18.7 lunar distances

    A body 495 m across, passing 18.7 lunar distances out at 18.03 km/s.

    +WHAT TO EXPECT
    SPEED
    18.03 km/srelative to Earth at closest approach
    MISS DISTANCE
    18.7 lunar distances7 180 573 km
    BRIGHTNESS
    magnitude 23.0far below anything an amateur telescope reaches
    SIZE
    495 mmeasured

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

[

November 2027

] 3 EVENTS
MO
TU
WE
TH
FR
SA
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1
2
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  • 2
    TUE
    FLYBY--:--

    (2017 QL33) passes at 8.1 lunar distances

    A body somewhere between 143 m and 321 m across depending on how dark its surface is, passing 8.1 lunar distances out at 7.82 km/s.

    +WHAT TO EXPECT
    SPEED
    7.82 km/srelative to Earth at closest approach
    MISS DISTANCE
    8.1 lunar distances3 110 557 km
    BRIGHTNESS
    magnitude 15.6far below anything an amateur telescope reaches
    SIZE
    143 m – 321 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 13
    SAT
    FLYBY--:--

    (2024 TW17) passes at 2.8 lunar distances

    A body somewhere between 118 m and 264 m across depending on how dark its surface is, passing 2.8 lunar distances out at 20.9 km/s.

    +WHAT TO EXPECT
    SPEED
    20.9 km/srelative to Earth at closest approach
    MISS DISTANCE
    2.8 lunar distances1 066 323 km
    BRIGHTNESS
    magnitude 14.2needs a telescope
    SIZE
    118 m – 264 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 28
    SUN
    FLYBY--:--

    (2019 UT6) passes at 13.2 lunar distances

    A body somewhere between 111 m and 248 m across depending on how dark its surface is, passing 13.2 lunar distances out at 11.79 km/s.

    +WHAT TO EXPECT
    SPEED
    11.79 km/srelative to Earth at closest approach
    MISS DISTANCE
    13.2 lunar distances5 084 446 km
    BRIGHTNESS
    magnitude 18.5far below anything an amateur telescope reaches
    SIZE
    111 m – 248 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

[

December 2027

] 2 EVENTS
MO
TU
WE
TH
FR
SA
SU
1
2
3
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  • 18
    SAT
    FLYBY--:--

    745311 (2010 XC15) passes at 19.8 lunar distances

    A body somewhere between 134 m and 301 m across depending on how dark its surface is, passing 19.8 lunar distances out at 8.89 km/s.

    +WHAT TO EXPECT
    SPEED
    8.89 km/srelative to Earth at closest approach
    MISS DISTANCE
    19.8 lunar distances7 620 326 km
    BRIGHTNESS
    magnitude 16.6far below anything an amateur telescope reaches
    SIZE
    134 m – 301 mfrom its brightness, the range covering a reflective surface and a sooty one

    This is a fact rather than a sight — far below what an amateur telescope reaches. It is listed because it is the kind of pass the surveys exist to catch, and because a calendar that only showed the visible ones would suggest the invisible ones are not happening.

  • 22
    WED
    SUN--:--

    December solstice

    December solstice: the Sun reaches its furthest from the equator, and the year turns.

    +WHAT TO EXPECT

    Nothing to see on the night. What it marks is the shape of the months either side: which way the nights are going, and how much dark you will have to work with.

28 events for the 18 months from today, of the kinds selected above. Times are instants, shown on your own clock; how every number here was made.

Nothing here is a hand-kept list. Every date except the flybys is solved from the same ephemeris the rest of the site uses to place the planets, at the moment you load the page; a meteor shower is dated by the longitude the Sun reaches rather than by a day of the month, which is why its date moves a little from year to year. The same events are available as JSON and CSV.

The 38 close approaches come from NASA/JPL Center for Near-Earth Object Studies, as they stood on 2026-08-30, and cover passes inside 20 lunar distances from 2026-07-31 through 2028-04-01. Unlike everything else on this page they cannot be computed from an ephemeris here — a newly discovered asteroid has no orbit until somebody measures one — so they are as complete as that date and no more.

[

COMMON QUESTIONS

] 10 ANSWERED
Why is there not an eclipse every month?
Because the Moon's orbit is tilted about five degrees to the Earth's, so at most new moons its shadow passes above or below us and misses. Eclipses arrive in seasons roughly twice a year, when the two orbital planes happen to line up with the Sun.
What fixes the date of a meteor shower?
Where the Earth is in its orbit, not the calendar. A shower is the Earth crossing a stream of dust a comet left behind, so the peak falls at the same point in the orbit every year and drifts by a few hours against the clock — which is why the dates here are solved rather than looked up.
Why are moon phases on a list of events?
Because moonlight decides what else is worth chasing. A full moon costs several magnitudes of faint detail across the whole sky, so the fortnight around new moon is when meteors, galaxies and nebulae actually repay the trip outside.
What is an opposition, and why is it the night to look?
Opposition is the moment an outer planet sits opposite the Sun from Earth, so it rises at sunset, stands highest at midnight and sets at sunrise. It falls close to the planet's nearest approach as well, which makes it the biggest and brightest that planet gets in the year.
What are the equinoxes and solstices, exactly?
The four instants at which the Sun reaches its furthest north, its furthest south, or crosses the celestial equator between the two. They are moments rather than days, and they are the same moment everywhere on Earth — which is why one of them can fall on a different date depending on your time zone.
How close does a listed flyby come?
Inside twenty lunar distances, which is about eight million kilometres. That is close by the standards of the Solar System and by no other standard at all: nothing on this list is a hazard, and the orbits are known accurately enough to say so well in advance.
Do I need to say where I am?
Not for the dates. An eclipse maximum, a shower peak or an opposition is the same instant everywhere. For whether the event clears your horizon at a sensible hour — and, for a solar eclipse, for whether you are standing inside a track a few hundred kilometres wide — the answer does depend on where you are, and the page will ask if you want it.
How far ahead can any of this be predicted?
Centuries, for anything driven by the positions of the Sun, Moon and planets: the ephemeris behind them holds up over far longer than a lifetime, and eclipse dates thousands of years out are routine. Meteor showers are the exception — the dates are firm and the strength is not, because it depends on how the dust happens to be distributed along the stream.
Why do the times differ by a few minutes from other sources?
Usually because a different thing is being timed. A shower peak is a broad maximum rather than an instant and different authorities quote it differently; a phase or an eclipse can be given in different time scales. Everything here comes from one ephemeris and is stated in one scale, so the events are at least consistent with each other.
Can I get these into my own calendar?
Yes. The whole window is published as a subscribable feed, so the events appear in whatever calendar application you already use and follow the solutions as they are recomputed.