Shailender Hatwal: Name of the asth sidhi in hanuman chalisa.
Swami Ram Swarup: Asht siddhis are acquired by a learned Yogi after studying Vedas, doing daily hawan, yajyen, name jaap of God and hard practice of Ashtang Yoga Philosophy under the guidance of a learned acharya of Vedas and Yoga Philosophy. Hanumanji was such a Yogi and being Yogi of such caliber he had eight siddhis(Asht siddhis) named :-

Samadhi gives eight siddhis i.e., Annima, Laghima, Mahima, Prapti , Praakaamya, Vashitva, Ishitatva, and jahan kaamvaasayitva vahan satyasankalpatah. So qualities of said siddhis are divine.

All these siddhis have been explained in Yajurveda mantra 7/4. So, the siddhis are not false. It is sad that in India, several saints who are against Vedas i.e., against the Almighty God, state that siddhis are not required. Their said statement is due to lack of knowledge of Vedas. Otherwise, who can go against the Vedas’ knowledge which emanates directly from Almighty God, Who is our father and nurses us.

N: Mere parivar ek sadasya mar gaya hai. ko kya jeevan main wo kabhi mil sakti hai
Swami Ram Swarup: Weh sab jo hamsey mrityu ke karann bichcherd jaatey hain weh dobaraa kabhi nahin milte hamein shanti aur dheeraj rakhna hota hai.

Narayanan: Charan Sparsh Swamiji, If hawan wrongly done, is there any side effects. According to my mother, she says don’t do any hawan without any proper knowledge otherwise it will give negative results. Pl guide. regards
Swami Ram Swarup: My blessings to you.

Actually, the procedure to perform hawan should be learnt first from a spiritual master who is learned of Vedas. If it is not possible, then at least Gayatri mantra should be listened from spiritual master then hawan from Gayatri mantra should be performed and slowly and steadily other hawan mantras should be learnt. For example:- if you feel that your pronunciation is not correct then a Cd of the hawan mantras can be sent form here. You may listen to Cd and perform hawan accordingly. I’ve also written a book named “Yajyen karma Sarvashreshth Ishwar Pooja” (in Hindi) in which process of performing hawan quoting Ved mantras and their word by word meaning have been mentioned. So, Cd + the above quoted book will help you.

Secondly, one should never worry that there will be side effects if hawan is done wrongly. The said bad views are being spread against the Vedas to stop doing hawan/Yajyen. You see, Almighty God is our Father and He sure helps us in Vedic path. We are his children and if in the beginning we do any mistake, He sure forgives us. But we will have to always do hard work to improve our knowledge under the guidance of a spiritual master.

So, don’t worry about negative result. You see, those who do not perform Vedic hawan, which is an order of Almighty God, they do some or the other worship daily and in the end they also pray to God “ to forgive their mistakes/faults” etc. So, what is wrong with the aspirant who follows Vedic eternal path and tries to perform Vedic hawan, which is mentioned in eternal knowledge of Vedas by God , Himself.