The origin of this variation is unknown. This variation, or modification, of the ASTRO convention is used to expedite the description of a Major suit two-suiter after a strong 1 No Trump opening with a range of 15-18 high card points, to show a two-suited holding.

Note: This variation carries the designation of Modified Astro to distinguish this modification from other variations of the original concept.

The bidding concept is as follows:

2 :	Indicates a long Heart suit and perhaps an unspecified long Minor suit.
2 :	Indicates Spades and an unspecified Minor suit.
2 :	Indicates Hearts and Spades.

Note: The continuations following both the 2 overcall or a 2 overcall are the same as they are for the ASTRO defense method.

If the partner of the 2 overcaller has a 4-card Heart suit or even a 3-card Heart suit, headed by at least 1 honor, then the partner should immediately bid 2 Hearts. If the partner cannot meet these requirements, then the partner of the overcaller should immediately bid 2, which communicates shortness in the Heart suit to the overcaller. The Diamond suit becomes the so-called neutral suit.

In the following sequence:

West		North		East		South		Meaning
1 NT								The No Trump range is 15-18 high card points.
		2						Indicates a long Heart suit and perhaps an unspecified long Minor suit.
				Pass				No bid at this time.
						2		Relay bid.
Pass		2						Promises a one-suited holding in Hearts with a second side suit in an unspecified Minor suit.

Only via the rebid of the overcaller does the partner know whether the overcaller has a one-suited holding or a long Heart suit accompanied with a second side-suit in one of the Minor suits. In the above example, North promises a holding, which contains only a one-suited Heart suit and no side suit in the Minors.

In the case that North holds a second, long side-suit in Diamonds, then North would pass the neutral bid of South. In the case that North holds a second, long side-suit in Clubs, then North would correct on his rebid to 3, or rebid 2, even with a 5-card Heart suit, and the choice is dependent on the relative strength of his holding and dependent on the relative strengths of his two possible suits.

Note: If the overcaller bids 2 after a 1 No Trump opening, showing specifically both Major suits, the responses are practically the same as for the Landy conventional defense method.

Note: If the overcaller is fortunate to establish a fit with the two Hearts overcall by his partner, then the advancer simply passes with weakness, invites with a stronger hand in Hearts, and bids game with an exceptionally good hand with strength and distribution.

If you wish to include this feature, or any other feature, of the game of bridge in your partnership agreement, then please make certain that the concept is understood by both partners. Be aware whether or not the feature is alertable or not and whether an announcement should or must be made. Check with the governing body and/or the bridge district and/or the bridge unit prior to the game to establish the guidelines applied. Please include the particular feature on your convention card in order that your opponents are also aware of this feature during the bidding process, since this information must be made known to them according to the Laws of Duplicate Contract Bridge. We do not always include the procedure regarding Alerts and/or Announcements, since these regulations are changed and revised during time by the governing body. It is our intention only to present the information as concisely and as accurately as possible.