Zero Shadow Day 2027 and 2028: Dates and Noon Time by City

Of the cities on this page, Thiruvananthapuram has the first Zero Shadow Day of 2027: 12 April 2027, at 12:23 IST. Bengaluru’s first is on 24 April at 12:17 and Chennai’s on 25 April at 12:06. Hyderabad’s turn is 9 May at 12:12, and Mumbai’s 16 May at 12:34. Each of them gets a second one on the Sun’s way back south: Mumbai on 28 July, Hyderabad on 4 August, Chennai on 18 August, Bengaluru on 19 August and Thiruvananthapuram on 31 August. Delhi gets none, in any year.

The tables below give both days of 2027 and of 2028 for the 24 cities on the site that lie south of the Tropic of Cancer, with the clock time of local noon on each. They are computed from the JPL DE421 ephemeris for each city’s centre. The page also measures how close to overhead the Sun actually gets, because “zero” is a slight overstatement.

When the Noon Sun Stands Overhead

At local noon the Sun stands due north or due south of the zenith, the point directly overhead. Its distance from the zenith is the difference between two angles: the place’s latitude and the Sun’s declination, its distance north or south of the celestial equator. Over a year the declination swings from about 23.4° south in December to 23.4° north in June and back. On the noon when the two come closest, the Sun is as near overhead as it gets, and an upright pole’s shadow falls almost entirely onto its own base.

That can only happen where the latitude is inside the band the declination sweeps, between the Tropic of Cancer and the Tropic of Capricorn. A city in that band is passed twice: once as the Sun moves north towards the June solstice and once as it comes back. Between the two days the noon Sun is north of the zenith, so the noon shadow points south; for the rest of the year it points north. The two days sit on either side of the June solstice, which falls on 21 June (IST) in both 2027 and 2028, and the gap between them shrinks the closer a city is to the tropic: 141 days at Thiruvananthapuram, 11 at Ranchi.

Zero Shadow Days of 2027, City by City

Cities run from south to north. The last column is the Sun’s distance from the zenith at the noon given, in arcminutes (sixty to a degree). The Sun’s own disc is about 32 arcminutes across, so every figure here means the zenith lies inside the disc at that moment.

Zero Shadow Days of 2028

Of the 48 days, 31 fall one calendar day earlier in 2028 than in 2027 and the rest keep the same date. None moves by more than a day. A tropical year is about 365 days and 6 hours, but 29 February 2028 puts the same calendar date 366 days later, so each crossing comes about 18 hours earlier by the calendar; whether the nearest noon moves back a day depends on the hour at which the crossing falls. The site’s astrologer city pages (Bengaluru’s, for one) give each tropical city a mean-year date from a short formula; in 2027 it matches the ephemeris day for 33 of the 48 and is a day off for the others.

How Small the Shadow Really Gets

The Sun is not a point, and that sets the limit. Measured to the centre of the disc, a one-metre pole’s shadow at noon on these days is three millimetres or less in every city in the table. But light from the edges of the disc arrives up to about 16 arcminutes off the vertical, which smears the shadow’s edge by roughly 4.7 mm either way for every metre of pole. On the day, what you see is a soft blot around the foot of the pole, not a crisp absence.

The day before and the day after look nearly the same. In the cities south of 21° N, the centre-to-centre shadow of a one-metre pole on the neighbouring noons is 2 to 9 mm, and the zenith sits inside the disc on at most three noons in a row. Closer to the tropic the Sun’s declination is changing slowly, because it is near its turning point, so the runs stretch out. At Kolkata, Indore and Ahmedabad they last five to eight noons. At Bhopal and Ranchi the two runs meet: the zenith is inside the disc at every noon from 10 June to 2 July at Bhopal, 23 noons, and from 12 June to 1 July at Ranchi, 20 noons. So the “day” there is better read as a season of three weeks around the solstice.

Why It Is Not at 12:00

The moment to watch is local noon, when the Sun crosses the meridian, and Indian Standard Time is set for 82.5° E. Each degree of longitude east of that line brings noon four minutes earlier and each degree west makes it four minutes later, before the seasonal correction below is added. Across the tropical cities in 2027 the noon on the day runs from 11:34 at Kolkata to 12:45 at Mumbai. The equation of time adds a seasonal correction on top, enough to put the same city’s two noons 11 minutes apart: Mumbai’s is 12:34 in May and 12:45 in July.

Noon moves by four minutes for every degree of longitude, so across a large city the minute can differ by one from one side to the other. The date does not change with longitude: it depends on latitude, and across a city the latitude changes far too little to move it. The city panchang pages show where each city’s noon sits against the clock through the year. Their sunrise and sunset come from a separate formula, and the midpoint of the two agrees with the ephemeris noon to within two minutes on every day in the tables above.

Why Delhi Has No Zero Shadow Day

Delhi is at 28.61° N, about five degrees north of the Tropic of Cancer, and the Sun never gets further north than the tropic. Its closest approach to Delhi’s zenith comes at noon on the June solstice, 5.18° short, when a one-metre pole still throws a 91 mm shadow to the north. The same holds for all 16 northern cities on the site. Among them the nearest miss is Udaipur, at 20 mm, and the farthest is Jammu, at 164 mm.

Not a Panchang Date

A Zero Shadow Day is set by the Sun’s declination, which follows the tropical year of the seasons. The panchang’s solar months follow the Sun through the sidereal rashis instead: in 2026 to 2028 the Sun enters sidereal Makara and Karka 23 to 26 days after the two solstices. So the two calendars do not line up, and no sankranti or tithi marks the day. Thiruvananthapuram’s April noon in 2027 comes while the Sun is still in sidereal Meena, two days before it enters Mesha on 14 April. Bengaluru’s two days fall with the Sun in Mesha and then in Simha. The Vedic Sun sign dates page gives the sidereal entries, and the Uttarayan and Dakshinayan page sets the solstices beside Makar and Karka Sankranti. The ayanamsa page explains the gap between the two zodiacs.

Shadows do have a place in the older reckoning. A siddhantic text records a place by its palabha, the noon shadow of a gnomon twelve angulas tall on an equinox day, and each astrologer city page prints that figure for its city. But no reading, muhurat or observance attaches to a Zero Shadow Day in the panchang, and this page gives none.

Watching It

Stand something straight and vertical on level ground in the sun, such as a pipe, a bottle or a pencil held plumb, a few minutes before the noon in the table, and watch its shadow shrink to its foot and turn. Watch the shadow, not the Sun. The minute matters more than the day: two minutes off noon move the Sun about half a degree from overhead, which already gives a longer shadow than the noon before or after. If cloud hides the Sun on the day, the noon before or after shows almost the same thing.

In Brief

• First of 2027: Thiruvananthapuram, 12 April, 12:23 IST
• Bengaluru 2027: 24 April and 19 August; 2028: 24 April and 18 August
• Chennai 2027: 25 April and 18 August; Hyderabad: 9 May and 4 August
• Mumbai 2027: 16 May and 28 July
• Near the tropic: at Bhopal and Ranchi the zenith stays inside the disc for about three weeks round the solstice
• Delhi and the north: never; Delhi’s shortest noon shadow is 91 mm per metre, on 21 June

The Sun’s other yearly turning points, the longest and shortest days, are on the Uttarayan page, and the six seasons on the ritu page. For the Moon’s distance at each full moon there is the supermoon page. In Hindi: ज़ीरो शैडो डे 2027 और 2028.