It could be that life, similar to that on Earth, flourishes on such planets. Doctor of Chemistry Nikolai Zhirov, covering the problem of atmosphere on the planets, pointed out that the organism of a Martian, for instance, could very well adapt itself to normal existence with a low body temperature. He said that he felt that the gaseous composition of the atmosphere of Mars was quite suitable to sustain life of beings which have become adapted to it.
The adaptability of organisms in different varieties of planets is described in the Brahma-saṁhitā as vibhūti-bhinnam, i.e., each and every one of the innumerable planets within the universes is endowed with a particular type of atmosphere, and the living beings there are advanced in science, psychology, etc., according to the superiority or inferiority of the atmosphere. Vibhūti means "specific power," and bhinnam means "variegated."
(Easy journey to other Planets).

Vibhūti means "specific power," and bhinnam means "variegated." Scientists who are attempting to explore outer space in an attempt to reach other planets by mechanical means must realize that organisms adapted to the atmosphere of the earth cannot exist in the atmospheres of other planets. As such, man's attempts to reach the moon, the sun, or Mars will be completely futile because of the different atmospheres prevailing on those planets. Individually, however, one can attempt to go to any planet he desires, but this is only possible by psychological changes in the mind. Mind is the nucleus of the material body. The gradual evolutionary progress of the material body depends on psychological changes within the mind. The change of the bodily construction of a worm into that of a butterfly and, in modern medical science, the conversion of a man's body into that of a woman (or vice versa) are more or less dependent on psychological changes.
(Easy journey to other Planets).

And in the same way, if one desires to enter into any other planet of the material sky, he can go there just after quitting the present body (i.e., after death). Thus if someone wants to go to the moon, the sun or Mars, he can do so simply by performing acts for that purpose. The Bhagavad-gītā confirms this statement in the following words:
That upon which a person meditates at the time of death, quitting his body absorbed in the thought thereof, that particular thing he attains after death.
(Easy journey to other Planets).

Ominous planets such as Mars and Saturn shone brighter and surpassed the auspicious ones such as Mercury, Jupiter and Venus as well as a number of lunar mansions. Taking seemingly retrograde courses, the planets came in conflict with one another.
The entire universe is moving under the three modes of material nature. Those living entities who are in goodness are called the pious species—pious lands, pious trees, etc. It is similar with the planets also; many planets are considered pious, and others are considered impious. Saturn and Mars are considered impious. When the pious planets shine very brightly, it is an auspicious sign, but when the inauspicious planets shine very brightly, this is not a very good sign.
(Srimad Bhagavatam------3:17:4------ translation and purport).

Above the moon by a distance of 200,000 yojanas are some stars, and above these stars is Śukra-graha (Venus), whose influence is always auspicious for the inhabitants of the entire universe. Above Śukra-graha by 200,000 yojanas is Budha-graha (Mercury), whose influence is sometimes auspicious and sometimes inauspicious. Next, above Budha-graha by 200,000 yojanas, isAṅgāraka (Mars), which almost always has an unfavorable influence. Above Aṅgāraka by another 200,000 yojanas is the planet called Bṛhaspati-graha (Jupiter), which is always very favorable for qualified brāhmaṇas. Above Bṛhaspati-graha is the planet Śanaiścara (Saturn), which is very inauspicious, and above Saturn is a group of seven stars occupied by great saintly persons who are always thinking of the welfare of the entire universe. These seven stars circumambulate Dhruvaloka, which is the residence of Lord Viṣṇu within this universe.
(Srimad Bhagavatam------5:22------summary).

Situated 1,600,000 miles above Mercury, or 8,800,000 miles above earth, is the planet Mars. If this planet does not travel in a crooked way, it crosses through each sign of the zodiac in three fortnights and in this way travels through all twelve, one after another. It almost always creates unfavorable conditions in respect to rainfall and other influences.
(Srimad Bhagavatam------5:22:14------translation).

Situated 1,600,000 miles above Mars, or 10,400,000 miles above earth, is the planet Jupiter, which travels through one sign of the zodiac within the period of a Parivatsara. If its movement is not curved, the planet Jupiter is very favorable to the brāhmaṇas of the universe.
(Srimad Bhagavatam------5:22:15------translation).

According to the description of this verse, the hundreds and thousands of stars and the great planets such as the sun, the moon, Venus, Mercury, Mars and Jupiter are not clustered together because of the law of gravity or any similar idea of the modern scientists. These planets and stars are all servants of the Supreme Personality of Godhead, Govinda or Kṛṣṇa, and according to His order they sit in their chariots and travel in their respective orbits. The orbits in which they move are compared to machines given by material nature to the operating deities of the stars and planets, who carry out the orders of the Supreme Personality of Godhead by revolving around Dhruvaloka, which is occupied by the great devotee Mahārāja Dhruva. This is confirmed in the Brahma-saṁhitā (5.52) as follows:
(Srimad Bhagavatam------5:23:3------translation).

On the upper chin of the śiśumāra is Agasti; on its lower chin, Yamarāja; on its mouth, Mars; on its genitals, Saturn; on the back of its neck, Jupiter; on its chest, the sun; and within the core of its heart, Nārāyaṇa. Within its mind is the moon; on its navel, Venus; and on its breasts, the Aśvinī-kumāras. Within its life air, which is known as prāṇāpāna, is Mercury, on its neck is Rāhu, all over its body are comets, and in its pores are the numerous stars.
(Srimad Bhagavatam------5:23:7------translation).

According to the Vedic description of the planetary system, all the planets move from east to west. The sun, the moon and five other planets, such as Mars and Jupiter, orbit one above another. Vāmanadeva, however, expanding His body and extending His steps, occupied the entire planetary system.
(Srimad Bhagavatam------5:21:31------purport).

The other three fourths of creation constitute the spiritual world. Among the innumerable planets in only one universe, the so-called scientists cannot understand even the Moon and Mars, but they try to defy the creation of the Supreme Lord and His uncommon energy. Such men have been described as crazy. Nūnaṁ pramattaḥ kurute vikarma (S.B.5:5:4). Such crazy men unnecessarily waste time, energy and money in attempting to defy the glorious activities of Urukrama, the Supreme Personality of Godhead.
(Srimad Bhagavatam------5:23:29------purport).

The explanation of the horoscope given by Bhaktivinoda Ṭhākura is that at the time of the birth of Lord Caitanya Mahāprabhu the planets were situated as follows: Śukra (Venus) was in Meṣa-rāśi (Aries) and the nakṣatra (lunar mansion) of Aśvinī; Ketu (the ninth planet) was in Siṁha-rāśi (Leo) and Uttaraphalgunī; Candra (the moon) was in Pūrvaphalgunī (the eleventh lunar mansion); Śani (Saturn) was in Vṛścika-rāśi (Scorpio) and Jyeṣthā; Bṛhaspati (Jupiter) was in Dhanu-rāśi (Sagittarius) and Pūrvāṣāḍhā; Maṅgala (Mars) was in Makara-rāśi (Capricorn) and Śravaṇā; Ravi (the sun) was in Kumbha-rāśi (Aquarius) and Pūrvabhādrapāda; Rāhu was in Pūrvabhādrapāda; and Budha (Mercury) was in Mīna-rāśi (Pisces) and Uttarabhādrapāda. The lagna was Siṁha.
(Sri Caitanya Caritamrta------1:13:89-------purport).