* Astronomy

There was no plane crash or any explosion of an aircraft Tuesday night, the Air Transportation Office said yesterday, after residents in some towns in northern Cebu reported such sightings.
ATO tower chief Manuel Tompar said all the 157 commercial flights between 11 p.m. Monday and 11 p.m. Tuesday were accounted for.
ATO’s thermal radar, which can pick up incoming and outgoing aircraft at an altitude of 20,000 feet and within a 64-mile radius, did not detect any crash.

"Our radar can pick up planes from the northernmost tip of Cebu to the southernmost end. Besides, if planes enter our air space, there is constant communication between the pilot and the tower until the plane lands" - Manuel Tompar.

Tompar said, though, that their radar cannot detect supersonic jets or a falling meteor because these travel faster than sound.
Very bright meteors are known as fireballs.
Some even thought they saw an unidentified flying object.
Weather specialists at the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pag-asa) in Mactan said the explosion may have been thunder due to the formation of cumulonimbus clouds.
Thunder from cumulonimbus clouds (a massive cloud formation) could be heard two to three kilometers away from its location.
Cumulonimbus clouds are hazardous to air navigation and as soon as they are sighted, Pag-asa informs ATO so aircraft could avoid them.
Cebu Provincial Police Office Director Vicente Loot also said there is no trace of a plane crash or a meteor shower in the northern part of Cebu late afternoon of Tuesday.
A loud explosion past 5 p.m. baffled residents in northern towns.
Loot ordered the police stations in the towns of Tuburan, Tabuelan, Borbon, Bogo and Sogod to investigate, but none reported seeing an object that fell from the sky.

"If an airplane crashed, the impact would not be heard in all towns in the north" - Vicente Loot.

Some residents of Tuburan said they saw a burning object that fell from the sky before the loud explosion.
Police Chief Rolando Yballe said people in the town were talking about the object but when they were asked where it fell, nobody could guide them.
PO1 Mariano Cajes of the Tabuelan police station said he and two other policemen were on patrol in Barangay Tabunok when they heard a powerful explosion.
Two weather experts from Pag-asa explained that cumulonimbus clouds could produce a thunder that can be heard within a radius of two to three kilometres.

"It is an air hazard cloud and we immediately inform ATO when we detect it in order to guide an aircraft from flying near it" - Vangie Tolentino and Jun Amarillo.

Tolentino said cumulonimbus clouds gather its strength by absorbing more water from the sea and as they become bigger, they create thunderstorms and heavy downpour.
Large cumulonimbus clouds are associated with powerful thunderstorms known as supercells, which produce frequent lightning, large hail, damaging winds and tornadoes.
These thunderstorms tend to develop during the afternoon and early evening when the effects of heating by the sun are strongest.

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